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Created: 2025-02-24 17:43

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/home/liu/actions-runner/_work/ccv/ccv/lib/3rdparty/sqlite3/sqlite3.h
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1
/*
2
** 2001-09-15
3
**
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** The author disclaims copyright to this source code.  In place of
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** a legal notice, here is a blessing:
6
**
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**    May you do good and not evil.
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**    May you find forgiveness for yourself and forgive others.
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**    May you share freely, never taking more than you give.
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**
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*************************************************************************
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** This header file defines the interface that the SQLite library
13
** presents to client programs.  If a C-function, structure, datatype,
14
** or constant definition does not appear in this file, then it is
15
** not a published API of SQLite, is subject to change without
16
** notice, and should not be referenced by programs that use SQLite.
17
**
18
** Some of the definitions that are in this file are marked as
19
** "experimental".  Experimental interfaces are normally new
20
** features recently added to SQLite.  We do not anticipate changes
21
** to experimental interfaces but reserve the right to make minor changes
22
** if experience from use "in the wild" suggest such changes are prudent.
23
**
24
** The official C-language API documentation for SQLite is derived
25
** from comments in this file.  This file is the authoritative source
26
** on how SQLite interfaces are supposed to operate.
27
**
28
** The name of this file under configuration management is "sqlite.h.in".
29
** The makefile makes some minor changes to this file (such as inserting
30
** the version number) and changes its name to "sqlite3.h" as
31
** part of the build process.
32
*/
33
#ifndef SQLITE3_H
34
#define SQLITE3_H
35
#include <stdarg.h>     /* Needed for the definition of va_list */
36
37
/*
38
** Make sure we can call this stuff from C++.
39
*/
40
#ifdef __cplusplus
41
extern "C" {
42
#endif
43
44
45
/*
46
** Facilitate override of interface linkage and calling conventions.
47
** Be aware that these macros may not be used within this particular
48
** translation of the amalgamation and its associated header file.
49
**
50
** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the
51
** compiler that the target identifier should have external linkage.
52
**
53
** The SQLITE_CDECL macro is used to set the calling convention for
54
** public functions that accept a variable number of arguments.
55
**
56
** The SQLITE_APICALL macro is used to set the calling convention for
57
** public functions that accept a fixed number of arguments.
58
**
59
** The SQLITE_STDCALL macro is no longer used and is now deprecated.
60
**
61
** The SQLITE_CALLBACK macro is used to set the calling convention for
62
** function pointers.
63
**
64
** The SQLITE_SYSAPI macro is used to set the calling convention for
65
** functions provided by the operating system.
66
**
67
** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and
68
** SQLITE_SYSAPI macros are used only when building for environments
69
** that require non-default calling conventions.
70
*/
71
#ifndef SQLITE_EXTERN
72
# define SQLITE_EXTERN extern
73
#endif
74
#ifndef SQLITE_API
75
# define SQLITE_API
76
#endif
77
#ifndef SQLITE_CDECL
78
# define SQLITE_CDECL
79
#endif
80
#ifndef SQLITE_APICALL
81
# define SQLITE_APICALL
82
#endif
83
#ifndef SQLITE_STDCALL
84
# define SQLITE_STDCALL SQLITE_APICALL
85
#endif
86
#ifndef SQLITE_CALLBACK
87
# define SQLITE_CALLBACK
88
#endif
89
#ifndef SQLITE_SYSAPI
90
# define SQLITE_SYSAPI
91
#endif
92
93
/*
94
** These no-op macros are used in front of interfaces to mark those
95
** interfaces as either deprecated or experimental.  New applications
96
** should not use deprecated interfaces - they are supported for backwards
97
** compatibility only.  Application writers should be aware that
98
** experimental interfaces are subject to change in point releases.
99
**
100
** These macros used to resolve to various kinds of compiler magic that
101
** would generate warning messages when they were used.  But that
102
** compiler magic ended up generating such a flurry of bug reports
103
** that we have taken it all out and gone back to using simple
104
** noop macros.
105
*/
106
#define SQLITE_DEPRECATED
107
#define SQLITE_EXPERIMENTAL
108
109
/*
110
** Ensure these symbols were not defined by some previous header file.
111
*/
112
#ifdef SQLITE_VERSION
113
# undef SQLITE_VERSION
114
#endif
115
#ifdef SQLITE_VERSION_NUMBER
116
# undef SQLITE_VERSION_NUMBER
117
#endif
118
119
/*
120
** CAPI3REF: Compile-Time Library Version Numbers
121
**
122
** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
123
** evaluates to a string literal that is the SQLite version in the
124
** format "X.Y.Z" where X is the major version number (always 3 for
125
** SQLite3) and Y is the minor version number and Z is the release number.)^
126
** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
127
** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
128
** numbers used in [SQLITE_VERSION].)^
129
** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
130
** be larger than the release from which it is derived.  Either Y will
131
** be held constant and Z will be incremented or else Y will be incremented
132
** and Z will be reset to zero.
133
**
134
** Since [version 3.6.18] ([dateof:3.6.18]),
135
** SQLite source code has been stored in the
136
** <a href="http://www.fossil-scm.org/">Fossil configuration management
137
** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
138
** a string which identifies a particular check-in of SQLite
139
** within its configuration management system.  ^The SQLITE_SOURCE_ID
140
** string contains the date and time of the check-in (UTC) and a SHA1
141
** or SHA3-256 hash of the entire source tree.  If the source code has
142
** been edited in any way since it was last checked in, then the last
143
** four hexadecimal digits of the hash may be modified.
144
**
145
** See also: [sqlite3_libversion()],
146
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
147
** [sqlite_version()] and [sqlite_source_id()].
148
*/
149
#define SQLITE_VERSION        "3.47.1"
150
#define SQLITE_VERSION_NUMBER 3047001
151
#define SQLITE_SOURCE_ID      "2024-11-25 12:07:48 b95d11e958643b969c47a8e5857f3793b9e69700b8f1469371386369a26e577e"
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153
/*
154
** CAPI3REF: Run-Time Library Version Numbers
155
** KEYWORDS: sqlite3_version sqlite3_sourceid
156
**
157
** These interfaces provide the same information as the [SQLITE_VERSION],
158
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
159
** but are associated with the library instead of the header file.  ^(Cautious
160
** programmers might include assert() statements in their application to
161
** verify that values returned by these interfaces match the macros in
162
** the header, and thus ensure that the application is
163
** compiled with matching library and header files.
164
**
165
** <blockquote><pre>
166
** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
167
** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
168
** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
169
** </pre></blockquote>)^
170
**
171
** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
172
** macro.  ^The sqlite3_libversion() function returns a pointer to the
173
** to the sqlite3_version[] string constant.  The sqlite3_libversion()
174
** function is provided for use in DLLs since DLL users usually do not have
175
** direct access to string constants within the DLL.  ^The
176
** sqlite3_libversion_number() function returns an integer equal to
177
** [SQLITE_VERSION_NUMBER].  ^(The sqlite3_sourceid() function returns
178
** a pointer to a string constant whose value is the same as the
179
** [SQLITE_SOURCE_ID] C preprocessor macro.  Except if SQLite is built
180
** using an edited copy of [the amalgamation], then the last four characters
181
** of the hash might be different from [SQLITE_SOURCE_ID].)^
182
**
183
** See also: [sqlite_version()] and [sqlite_source_id()].
184
*/
185
SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
186
SQLITE_API const char *sqlite3_libversion(void);
187
SQLITE_API const char *sqlite3_sourceid(void);
188
SQLITE_API int sqlite3_libversion_number(void);
189
190
/*
191
** CAPI3REF: Run-Time Library Compilation Options Diagnostics
192
**
193
** ^The sqlite3_compileoption_used() function returns 0 or 1
194
** indicating whether the specified option was defined at
195
** compile time.  ^The SQLITE_ prefix may be omitted from the
196
** option name passed to sqlite3_compileoption_used().
197
**
198
** ^The sqlite3_compileoption_get() function allows iterating
199
** over the list of options that were defined at compile time by
200
** returning the N-th compile time option string.  ^If N is out of range,
201
** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_
202
** prefix is omitted from any strings returned by
203
** sqlite3_compileoption_get().
204
**
205
** ^Support for the diagnostic functions sqlite3_compileoption_used()
206
** and sqlite3_compileoption_get() may be omitted by specifying the
207
** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
208
**
209
** See also: SQL functions [sqlite_compileoption_used()] and
210
** [sqlite_compileoption_get()] and the [compile_options pragma].
211
*/
212
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
213
SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
214
SQLITE_API const char *sqlite3_compileoption_get(int N);
215
#else
216
# define sqlite3_compileoption_used(X) 0
217
# define sqlite3_compileoption_get(X)  ((void*)0)
218
#endif
219
220
/*
221
** CAPI3REF: Test To See If The Library Is Threadsafe
222
**
223
** ^The sqlite3_threadsafe() function returns zero if and only if
224
** SQLite was compiled with mutexing code omitted due to the
225
** [SQLITE_THREADSAFE] compile-time option being set to 0.
226
**
227
** SQLite can be compiled with or without mutexes.  When
228
** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
229
** are enabled and SQLite is threadsafe.  When the
230
** [SQLITE_THREADSAFE] macro is 0,
231
** the mutexes are omitted.  Without the mutexes, it is not safe
232
** to use SQLite concurrently from more than one thread.
233
**
234
** Enabling mutexes incurs a measurable performance penalty.
235
** So if speed is of utmost importance, it makes sense to disable
236
** the mutexes.  But for maximum safety, mutexes should be enabled.
237
** ^The default behavior is for mutexes to be enabled.
238
**
239
** This interface can be used by an application to make sure that the
240
** version of SQLite that it is linking against was compiled with
241
** the desired setting of the [SQLITE_THREADSAFE] macro.
242
**
243
** This interface only reports on the compile-time mutex setting
244
** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
245
** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
246
** can be fully or partially disabled using a call to [sqlite3_config()]
247
** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
248
** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
249
** sqlite3_threadsafe() function shows only the compile-time setting of
250
** thread safety, not any run-time changes to that setting made by
251
** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
252
** is unchanged by calls to sqlite3_config().)^
253
**
254
** See the [threading mode] documentation for additional information.
255
*/
256
SQLITE_API int sqlite3_threadsafe(void);
257
258
/*
259
** CAPI3REF: Database Connection Handle
260
** KEYWORDS: {database connection} {database connections}
261
**
262
** Each open SQLite database is represented by a pointer to an instance of
263
** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
264
** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
265
** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
266
** and [sqlite3_close_v2()] are its destructors.  There are many other
267
** interfaces (such as
268
** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
269
** [sqlite3_busy_timeout()] to name but three) that are methods on an
270
** sqlite3 object.
271
*/
272
typedef struct sqlite3 sqlite3;
273
274
/*
275
** CAPI3REF: 64-Bit Integer Types
276
** KEYWORDS: sqlite_int64 sqlite_uint64
277
**
278
** Because there is no cross-platform way to specify 64-bit integer types
279
** SQLite includes typedefs for 64-bit signed and unsigned integers.
280
**
281
** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
282
** The sqlite_int64 and sqlite_uint64 types are supported for backwards
283
** compatibility only.
284
**
285
** ^The sqlite3_int64 and sqlite_int64 types can store integer values
286
** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
287
** sqlite3_uint64 and sqlite_uint64 types can store integer values
288
** between 0 and +18446744073709551615 inclusive.
289
*/
290
#ifdef SQLITE_INT64_TYPE
291
  typedef SQLITE_INT64_TYPE sqlite_int64;
292
# ifdef SQLITE_UINT64_TYPE
293
    typedef SQLITE_UINT64_TYPE sqlite_uint64;
294
# else
295
    typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
296
# endif
297
#elif defined(_MSC_VER) || defined(__BORLANDC__)
298
  typedef __int64 sqlite_int64;
299
  typedef unsigned __int64 sqlite_uint64;
300
#else
301
  typedef long long int sqlite_int64;
302
  typedef unsigned long long int sqlite_uint64;
303
#endif
304
typedef sqlite_int64 sqlite3_int64;
305
typedef sqlite_uint64 sqlite3_uint64;
306
307
/*
308
** If compiling for a processor that lacks floating point support,
309
** substitute integer for floating-point.
310
*/
311
#ifdef SQLITE_OMIT_FLOATING_POINT
312
# define double sqlite3_int64
313
#endif
314
315
/*
316
** CAPI3REF: Closing A Database Connection
317
** DESTRUCTOR: sqlite3
318
**
319
** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
320
** for the [sqlite3] object.
321
** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
322
** the [sqlite3] object is successfully destroyed and all associated
323
** resources are deallocated.
324
**
325
** Ideally, applications should [sqlite3_finalize | finalize] all
326
** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and
327
** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
328
** with the [sqlite3] object prior to attempting to close the object.
329
** ^If the database connection is associated with unfinalized prepared
330
** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
331
** sqlite3_close() will leave the database connection open and return
332
** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
333
** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
334
** it returns [SQLITE_OK] regardless, but instead of deallocating the database
335
** connection immediately, it marks the database connection as an unusable
336
** "zombie" and makes arrangements to automatically deallocate the database
337
** connection after all prepared statements are finalized, all BLOB handles
338
** are closed, and all backups have finished. The sqlite3_close_v2() interface
339
** is intended for use with host languages that are garbage collected, and
340
** where the order in which destructors are called is arbitrary.
341
**
342
** ^If an [sqlite3] object is destroyed while a transaction is open,
343
** the transaction is automatically rolled back.
344
**
345
** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
346
** must be either a NULL
347
** pointer or an [sqlite3] object pointer obtained
348
** from [sqlite3_open()], [sqlite3_open16()], or
349
** [sqlite3_open_v2()], and not previously closed.
350
** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
351
** argument is a harmless no-op.
352
*/
353
SQLITE_API int sqlite3_close(sqlite3*);
354
SQLITE_API int sqlite3_close_v2(sqlite3*);
355
356
/*
357
** The type for a callback function.
358
** This is legacy and deprecated.  It is included for historical
359
** compatibility and is not documented.
360
*/
361
typedef int (*sqlite3_callback)(void*,int,char**, char**);
362
363
/*
364
** CAPI3REF: One-Step Query Execution Interface
365
** METHOD: sqlite3
366
**
367
** The sqlite3_exec() interface is a convenience wrapper around
368
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
369
** that allows an application to run multiple statements of SQL
370
** without having to use a lot of C code.
371
**
372
** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
373
** semicolon-separate SQL statements passed into its 2nd argument,
374
** in the context of the [database connection] passed in as its 1st
375
** argument.  ^If the callback function of the 3rd argument to
376
** sqlite3_exec() is not NULL, then it is invoked for each result row
377
** coming out of the evaluated SQL statements.  ^The 4th argument to
378
** sqlite3_exec() is relayed through to the 1st argument of each
379
** callback invocation.  ^If the callback pointer to sqlite3_exec()
380
** is NULL, then no callback is ever invoked and result rows are
381
** ignored.
382
**
383
** ^If an error occurs while evaluating the SQL statements passed into
384
** sqlite3_exec(), then execution of the current statement stops and
385
** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
386
** is not NULL then any error message is written into memory obtained
387
** from [sqlite3_malloc()] and passed back through the 5th parameter.
388
** To avoid memory leaks, the application should invoke [sqlite3_free()]
389
** on error message strings returned through the 5th parameter of
390
** sqlite3_exec() after the error message string is no longer needed.
391
** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
392
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
393
** NULL before returning.
394
**
395
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
396
** routine returns SQLITE_ABORT without invoking the callback again and
397
** without running any subsequent SQL statements.
398
**
399
** ^The 2nd argument to the sqlite3_exec() callback function is the
400
** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
401
** callback is an array of pointers to strings obtained as if from
402
** [sqlite3_column_text()], one for each column.  ^If an element of a
403
** result row is NULL then the corresponding string pointer for the
404
** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
405
** sqlite3_exec() callback is an array of pointers to strings where each
406
** entry represents the name of corresponding result column as obtained
407
** from [sqlite3_column_name()].
408
**
409
** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
410
** to an empty string, or a pointer that contains only whitespace and/or
411
** SQL comments, then no SQL statements are evaluated and the database
412
** is not changed.
413
**
414
** Restrictions:
415
**
416
** <ul>
417
** <li> The application must ensure that the 1st parameter to sqlite3_exec()
418
**      is a valid and open [database connection].
419
** <li> The application must not close the [database connection] specified by
420
**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
421
** <li> The application must not modify the SQL statement text passed into
422
**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
423
** <li> The application must not dereference the arrays or string pointers
424
**       passed as the 3rd and 4th callback parameters after it returns.
425
** </ul>
426
*/
427
SQLITE_API int sqlite3_exec(
428
  sqlite3*,                                  /* An open database */
429
  const char *sql,                           /* SQL to be evaluated */
430
  int (*callback)(void*,int,char**,char**),  /* Callback function */
431
  void *,                                    /* 1st argument to callback */
432
  char **errmsg                              /* Error msg written here */
433
);
434
435
/*
436
** CAPI3REF: Result Codes
437
** KEYWORDS: {result code definitions}
438
**
439
** Many SQLite functions return an integer result code from the set shown
440
** here in order to indicate success or failure.
441
**
442
** New error codes may be added in future versions of SQLite.
443
**
444
** See also: [extended result code definitions]
445
*/
446
50
#define SQLITE_OK           0   /* Successful result */
447
/* beginning-of-error-codes */
448
#define SQLITE_ERROR        1   /* Generic error */
449
#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
450
#define SQLITE_PERM         3   /* Access permission denied */
451
#define SQLITE_ABORT        4   /* Callback routine requested an abort */
452
#define SQLITE_BUSY         5   /* The database file is locked */
453
#define SQLITE_LOCKED       6   /* A table in the database is locked */
454
#define SQLITE_NOMEM        7   /* A malloc() failed */
455
#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
456
#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
457
#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
458
#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
459
#define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
460
#define SQLITE_FULL        13   /* Insertion failed because database is full */
461
#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
462
#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
463
#define SQLITE_EMPTY       16   /* Internal use only */
464
#define SQLITE_SCHEMA      17   /* The database schema changed */
465
#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
466
#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
467
#define SQLITE_MISMATCH    20   /* Data type mismatch */
468
#define SQLITE_MISUSE      21   /* Library used incorrectly */
469
#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
470
#define SQLITE_AUTH        23   /* Authorization denied */
471
#define SQLITE_FORMAT      24   /* Not used */
472
#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
473
#define SQLITE_NOTADB      26   /* File opened that is not a database file */
474
#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
475
#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
476
134
#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
477
#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
478
/* end-of-error-codes */
479
480
/*
481
** CAPI3REF: Extended Result Codes
482
** KEYWORDS: {extended result code definitions}
483
**
484
** In its default configuration, SQLite API routines return one of 30 integer
485
** [result codes].  However, experience has shown that many of
486
** these result codes are too coarse-grained.  They do not provide as
487
** much information about problems as programmers might like.  In an effort to
488
** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
489
** and later) include
490
** support for additional result codes that provide more detailed information
491
** about errors. These [extended result codes] are enabled or disabled
492
** on a per database connection basis using the
493
** [sqlite3_extended_result_codes()] API.  Or, the extended code for
494
** the most recent error can be obtained using
495
** [sqlite3_extended_errcode()].
496
*/
497
#define SQLITE_ERROR_MISSING_COLLSEQ   (SQLITE_ERROR | (1<<8))
498
#define SQLITE_ERROR_RETRY             (SQLITE_ERROR | (2<<8))
499
#define SQLITE_ERROR_SNAPSHOT          (SQLITE_ERROR | (3<<8))
500
#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
501
#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
502
#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
503
#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
504
#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
505
#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
506
#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
507
#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
508
#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
509
#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
510
#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
511
#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
512
#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
513
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
514
#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
515
#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
516
#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
517
#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
518
#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
519
#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
520
#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
521
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
522
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
523
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
524
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
525
#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
526
#define SQLITE_IOERR_VNODE             (SQLITE_IOERR | (27<<8))
527
#define SQLITE_IOERR_AUTH              (SQLITE_IOERR | (28<<8))
528
#define SQLITE_IOERR_BEGIN_ATOMIC      (SQLITE_IOERR | (29<<8))
529
#define SQLITE_IOERR_COMMIT_ATOMIC     (SQLITE_IOERR | (30<<8))
530
#define SQLITE_IOERR_ROLLBACK_ATOMIC   (SQLITE_IOERR | (31<<8))
531
#define SQLITE_IOERR_DATA              (SQLITE_IOERR | (32<<8))
532
#define SQLITE_IOERR_CORRUPTFS         (SQLITE_IOERR | (33<<8))
533
#define SQLITE_IOERR_IN_PAGE           (SQLITE_IOERR | (34<<8))
534
#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
535
#define SQLITE_LOCKED_VTAB             (SQLITE_LOCKED |  (2<<8))
536
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
537
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
538
#define SQLITE_BUSY_TIMEOUT            (SQLITE_BUSY   |  (3<<8))
539
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
540
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
541
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
542
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
543
#define SQLITE_CANTOPEN_DIRTYWAL       (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
544
#define SQLITE_CANTOPEN_SYMLINK        (SQLITE_CANTOPEN | (6<<8))
545
#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
546
#define SQLITE_CORRUPT_SEQUENCE        (SQLITE_CORRUPT | (2<<8))
547
#define SQLITE_CORRUPT_INDEX           (SQLITE_CORRUPT | (3<<8))
548
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
549
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
550
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
551
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
552
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
553
#define SQLITE_READONLY_DIRECTORY      (SQLITE_READONLY | (6<<8))
554
#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
555
#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
556
#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
557
#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
558
#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
559
#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
560
#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
561
#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
562
#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
563
#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
564
#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
565
#define SQLITE_CONSTRAINT_PINNED       (SQLITE_CONSTRAINT |(11<<8))
566
#define SQLITE_CONSTRAINT_DATATYPE     (SQLITE_CONSTRAINT |(12<<8))
567
#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
568
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
569
#define SQLITE_NOTICE_RBU              (SQLITE_NOTICE | (3<<8))
570
#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
571
#define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
572
#define SQLITE_OK_LOAD_PERMANENTLY     (SQLITE_OK | (1<<8))
573
#define SQLITE_OK_SYMLINK              (SQLITE_OK | (2<<8)) /* internal use only */
574
575
/*
576
** CAPI3REF: Flags For File Open Operations
577
**
578
** These bit values are intended for use in the
579
** 3rd parameter to the [sqlite3_open_v2()] interface and
580
** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
581
**
582
** Only those flags marked as "Ok for sqlite3_open_v2()" may be
583
** used as the third argument to the [sqlite3_open_v2()] interface.
584
** The other flags have historically been ignored by sqlite3_open_v2(),
585
** though future versions of SQLite might change so that an error is
586
** raised if any of the disallowed bits are passed into sqlite3_open_v2().
587
** Applications should not depend on the historical behavior.
588
**
589
** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into
590
** [sqlite3_open_v2()] does *not* cause the underlying database file
591
** to be opened using O_EXCL.  Passing SQLITE_OPEN_EXCLUSIVE into
592
** [sqlite3_open_v2()] has historically be a no-op and might become an
593
** error in future versions of SQLite.
594
*/
595
#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
596
#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
597
#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
598
#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
599
#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
600
#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
601
#define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
602
#define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
603
#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
604
#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
605
#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
606
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
607
#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
608
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
609
#define SQLITE_OPEN_SUPER_JOURNAL    0x00004000  /* VFS only */
610
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
611
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
612
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
613
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
614
#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
615
#define SQLITE_OPEN_NOFOLLOW         0x01000000  /* Ok for sqlite3_open_v2() */
616
#define SQLITE_OPEN_EXRESCODE        0x02000000  /* Extended result codes */
617
618
/* Reserved:                         0x00F00000 */
619
/* Legacy compatibility: */
620
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
621
622
623
/*
624
** CAPI3REF: Device Characteristics
625
**
626
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
627
** object returns an integer which is a vector of these
628
** bit values expressing I/O characteristics of the mass storage
629
** device that holds the file that the [sqlite3_io_methods]
630
** refers to.
631
**
632
** The SQLITE_IOCAP_ATOMIC property means that all writes of
633
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
634
** mean that writes of blocks that are nnn bytes in size and
635
** are aligned to an address which is an integer multiple of
636
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
637
** that when data is appended to a file, the data is appended
638
** first then the size of the file is extended, never the other
639
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
640
** information is written to disk in the same order as calls
641
** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
642
** after reboot following a crash or power loss, the only bytes in a
643
** file that were written at the application level might have changed
644
** and that adjacent bytes, even bytes within the same sector are
645
** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
646
** flag indicates that a file cannot be deleted when open.  The
647
** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
648
** read-only media and cannot be changed even by processes with
649
** elevated privileges.
650
**
651
** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
652
** filesystem supports doing multiple write operations atomically when those
653
** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
654
** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
655
**
656
** The SQLITE_IOCAP_SUBPAGE_READ property means that it is ok to read
657
** from the database file in amounts that are not a multiple of the
658
** page size and that do not begin at a page boundary.  Without this
659
** property, SQLite is careful to only do full-page reads and write
660
** on aligned pages, with the one exception that it will do a sub-page
661
** read of the first page to access the database header.
662
*/
663
#define SQLITE_IOCAP_ATOMIC                 0x00000001
664
#define SQLITE_IOCAP_ATOMIC512              0x00000002
665
#define SQLITE_IOCAP_ATOMIC1K               0x00000004
666
#define SQLITE_IOCAP_ATOMIC2K               0x00000008
667
#define SQLITE_IOCAP_ATOMIC4K               0x00000010
668
#define SQLITE_IOCAP_ATOMIC8K               0x00000020
669
#define SQLITE_IOCAP_ATOMIC16K              0x00000040
670
#define SQLITE_IOCAP_ATOMIC32K              0x00000080
671
#define SQLITE_IOCAP_ATOMIC64K              0x00000100
672
#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
673
#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
674
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
675
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
676
#define SQLITE_IOCAP_IMMUTABLE              0x00002000
677
#define SQLITE_IOCAP_BATCH_ATOMIC           0x00004000
678
#define SQLITE_IOCAP_SUBPAGE_READ           0x00008000
679
680
/*
681
** CAPI3REF: File Locking Levels
682
**
683
** SQLite uses one of these integer values as the second
684
** argument to calls it makes to the xLock() and xUnlock() methods
685
** of an [sqlite3_io_methods] object.  These values are ordered from
686
** lest restrictive to most restrictive.
687
**
688
** The argument to xLock() is always SHARED or higher.  The argument to
689
** xUnlock is either SHARED or NONE.
690
*/
691
#define SQLITE_LOCK_NONE          0       /* xUnlock() only */
692
#define SQLITE_LOCK_SHARED        1       /* xLock() or xUnlock() */
693
#define SQLITE_LOCK_RESERVED      2       /* xLock() only */
694
#define SQLITE_LOCK_PENDING       3       /* xLock() only */
695
#define SQLITE_LOCK_EXCLUSIVE     4       /* xLock() only */
696
697
/*
698
** CAPI3REF: Synchronization Type Flags
699
**
700
** When SQLite invokes the xSync() method of an
701
** [sqlite3_io_methods] object it uses a combination of
702
** these integer values as the second argument.
703
**
704
** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
705
** sync operation only needs to flush data to mass storage.  Inode
706
** information need not be flushed. If the lower four bits of the flag
707
** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
708
** If the lower four bits equal SQLITE_SYNC_FULL, that means
709
** to use Mac OS X style fullsync instead of fsync().
710
**
711
** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
712
** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
713
** settings.  The [synchronous pragma] determines when calls to the
714
** xSync VFS method occur and applies uniformly across all platforms.
715
** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
716
** energetic or rigorous or forceful the sync operations are and
717
** only make a difference on Mac OSX for the default SQLite code.
718
** (Third-party VFS implementations might also make the distinction
719
** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
720
** operating systems natively supported by SQLite, only Mac OSX
721
** cares about the difference.)
722
*/
723
#define SQLITE_SYNC_NORMAL        0x00002
724
#define SQLITE_SYNC_FULL          0x00003
725
#define SQLITE_SYNC_DATAONLY      0x00010
726
727
/*
728
** CAPI3REF: OS Interface Open File Handle
729
**
730
** An [sqlite3_file] object represents an open file in the
731
** [sqlite3_vfs | OS interface layer].  Individual OS interface
732
** implementations will
733
** want to subclass this object by appending additional fields
734
** for their own use.  The pMethods entry is a pointer to an
735
** [sqlite3_io_methods] object that defines methods for performing
736
** I/O operations on the open file.
737
*/
738
typedef struct sqlite3_file sqlite3_file;
739
struct sqlite3_file {
740
  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
741
};
742
743
/*
744
** CAPI3REF: OS Interface File Virtual Methods Object
745
**
746
** Every file opened by the [sqlite3_vfs.xOpen] method populates an
747
** [sqlite3_file] object (or, more commonly, a subclass of the
748
** [sqlite3_file] object) with a pointer to an instance of this object.
749
** This object defines the methods used to perform various operations
750
** against the open file represented by the [sqlite3_file] object.
751
**
752
** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
753
** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
754
** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
755
** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
756
** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
757
** to NULL.
758
**
759
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
760
** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
761
** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
762
** flag may be ORed in to indicate that only the data of the file
763
** and not its inode needs to be synced.
764
**
765
** The integer values to xLock() and xUnlock() are one of
766
** <ul>
767
** <li> [SQLITE_LOCK_NONE],
768
** <li> [SQLITE_LOCK_SHARED],
769
** <li> [SQLITE_LOCK_RESERVED],
770
** <li> [SQLITE_LOCK_PENDING], or
771
** <li> [SQLITE_LOCK_EXCLUSIVE].
772
** </ul>
773
** xLock() upgrades the database file lock.  In other words, xLock() moves the
774
** database file lock in the direction NONE toward EXCLUSIVE. The argument to
775
** xLock() is always one of SHARED, RESERVED, PENDING, or EXCLUSIVE, never
776
** SQLITE_LOCK_NONE.  If the database file lock is already at or above the
777
** requested lock, then the call to xLock() is a no-op.
778
** xUnlock() downgrades the database file lock to either SHARED or NONE.
779
** If the lock is already at or below the requested lock state, then the call
780
** to xUnlock() is a no-op.
781
** The xCheckReservedLock() method checks whether any database connection,
782
** either in this process or in some other process, is holding a RESERVED,
783
** PENDING, or EXCLUSIVE lock on the file.  It returns, via its output
784
** pointer parameter, true if such a lock exists and false otherwise.
785
**
786
** The xFileControl() method is a generic interface that allows custom
787
** VFS implementations to directly control an open file using the
788
** [sqlite3_file_control()] interface.  The second "op" argument is an
789
** integer opcode.  The third argument is a generic pointer intended to
790
** point to a structure that may contain arguments or space in which to
791
** write return values.  Potential uses for xFileControl() might be
792
** functions to enable blocking locks with timeouts, to change the
793
** locking strategy (for example to use dot-file locks), to inquire
794
** about the status of a lock, or to break stale locks.  The SQLite
795
** core reserves all opcodes less than 100 for its own use.
796
** A [file control opcodes | list of opcodes] less than 100 is available.
797
** Applications that define a custom xFileControl method should use opcodes
798
** greater than 100 to avoid conflicts.  VFS implementations should
799
** return [SQLITE_NOTFOUND] for file control opcodes that they do not
800
** recognize.
801
**
802
** The xSectorSize() method returns the sector size of the
803
** device that underlies the file.  The sector size is the
804
** minimum write that can be performed without disturbing
805
** other bytes in the file.  The xDeviceCharacteristics()
806
** method returns a bit vector describing behaviors of the
807
** underlying device:
808
**
809
** <ul>
810
** <li> [SQLITE_IOCAP_ATOMIC]
811
** <li> [SQLITE_IOCAP_ATOMIC512]
812
** <li> [SQLITE_IOCAP_ATOMIC1K]
813
** <li> [SQLITE_IOCAP_ATOMIC2K]
814
** <li> [SQLITE_IOCAP_ATOMIC4K]
815
** <li> [SQLITE_IOCAP_ATOMIC8K]
816
** <li> [SQLITE_IOCAP_ATOMIC16K]
817
** <li> [SQLITE_IOCAP_ATOMIC32K]
818
** <li> [SQLITE_IOCAP_ATOMIC64K]
819
** <li> [SQLITE_IOCAP_SAFE_APPEND]
820
** <li> [SQLITE_IOCAP_SEQUENTIAL]
821
** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
822
** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
823
** <li> [SQLITE_IOCAP_IMMUTABLE]
824
** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
825
** <li> [SQLITE_IOCAP_SUBPAGE_READ]
826
** </ul>
827
**
828
** The SQLITE_IOCAP_ATOMIC property means that all writes of
829
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
830
** mean that writes of blocks that are nnn bytes in size and
831
** are aligned to an address which is an integer multiple of
832
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
833
** that when data is appended to a file, the data is appended
834
** first then the size of the file is extended, never the other
835
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
836
** information is written to disk in the same order as calls
837
** to xWrite().
838
**
839
** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
840
** in the unread portions of the buffer with zeros.  A VFS that
841
** fails to zero-fill short reads might seem to work.  However,
842
** failure to zero-fill short reads will eventually lead to
843
** database corruption.
844
*/
845
typedef struct sqlite3_io_methods sqlite3_io_methods;
846
struct sqlite3_io_methods {
847
  int iVersion;
848
  int (*xClose)(sqlite3_file*);
849
  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
850
  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
851
  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
852
  int (*xSync)(sqlite3_file*, int flags);
853
  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
854
  int (*xLock)(sqlite3_file*, int);
855
  int (*xUnlock)(sqlite3_file*, int);
856
  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
857
  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
858
  int (*xSectorSize)(sqlite3_file*);
859
  int (*xDeviceCharacteristics)(sqlite3_file*);
860
  /* Methods above are valid for version 1 */
861
  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
862
  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
863
  void (*xShmBarrier)(sqlite3_file*);
864
  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
865
  /* Methods above are valid for version 2 */
866
  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
867
  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
868
  /* Methods above are valid for version 3 */
869
  /* Additional methods may be added in future releases */
870
};
871
872
/*
873
** CAPI3REF: Standard File Control Opcodes
874
** KEYWORDS: {file control opcodes} {file control opcode}
875
**
876
** These integer constants are opcodes for the xFileControl method
877
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
878
** interface.
879
**
880
** <ul>
881
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
882
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
883
** opcode causes the xFileControl method to write the current state of
884
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
885
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
886
** into an integer that the pArg argument points to.
887
** This capability is only available if SQLite is compiled with [SQLITE_DEBUG].
888
**
889
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
890
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
891
** layer a hint of how large the database file will grow to be during the
892
** current transaction.  This hint is not guaranteed to be accurate but it
893
** is often close.  The underlying VFS might choose to preallocate database
894
** file space based on this hint in order to help writes to the database
895
** file run faster.
896
**
897
** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
898
** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
899
** implements [sqlite3_deserialize()] to set an upper bound on the size
900
** of the in-memory database.  The argument is a pointer to a [sqlite3_int64].
901
** If the integer pointed to is negative, then it is filled in with the
902
** current limit.  Otherwise the limit is set to the larger of the value
903
** of the integer pointed to and the current database size.  The integer
904
** pointed to is set to the new limit.
905
**
906
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
907
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
908
** extends and truncates the database file in chunks of a size specified
909
** by the user. The fourth argument to [sqlite3_file_control()] should
910
** point to an integer (type int) containing the new chunk-size to use
911
** for the nominated database. Allocating database file space in large
912
** chunks (say 1MB at a time), may reduce file-system fragmentation and
913
** improve performance on some systems.
914
**
915
** <li>[[SQLITE_FCNTL_FILE_POINTER]]
916
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
917
** to the [sqlite3_file] object associated with a particular database
918
** connection.  See also [SQLITE_FCNTL_JOURNAL_POINTER].
919
**
920
** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
921
** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
922
** to the [sqlite3_file] object associated with the journal file (either
923
** the [rollback journal] or the [write-ahead log]) for a particular database
924
** connection.  See also [SQLITE_FCNTL_FILE_POINTER].
925
**
926
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
927
** No longer in use.
928
**
929
** <li>[[SQLITE_FCNTL_SYNC]]
930
** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
931
** sent to the VFS immediately before the xSync method is invoked on a
932
** database file descriptor. Or, if the xSync method is not invoked
933
** because the user has configured SQLite with
934
** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
935
** of the xSync method. In most cases, the pointer argument passed with
936
** this file-control is NULL. However, if the database file is being synced
937
** as part of a multi-database commit, the argument points to a nul-terminated
938
** string containing the transactions super-journal file name. VFSes that
939
** do not need this signal should silently ignore this opcode. Applications
940
** should not call [sqlite3_file_control()] with this opcode as doing so may
941
** disrupt the operation of the specialized VFSes that do require it.
942
**
943
** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
944
** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
945
** and sent to the VFS after a transaction has been committed immediately
946
** but before the database is unlocked. VFSes that do not need this signal
947
** should silently ignore this opcode. Applications should not call
948
** [sqlite3_file_control()] with this opcode as doing so may disrupt the
949
** operation of the specialized VFSes that do require it.
950
**
951
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
952
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
953
** retry counts and intervals for certain disk I/O operations for the
954
** windows [VFS] in order to provide robustness in the presence of
955
** anti-virus programs.  By default, the windows VFS will retry file read,
956
** file write, and file delete operations up to 10 times, with a delay
957
** of 25 milliseconds before the first retry and with the delay increasing
958
** by an additional 25 milliseconds with each subsequent retry.  This
959
** opcode allows these two values (10 retries and 25 milliseconds of delay)
960
** to be adjusted.  The values are changed for all database connections
961
** within the same process.  The argument is a pointer to an array of two
962
** integers where the first integer is the new retry count and the second
963
** integer is the delay.  If either integer is negative, then the setting
964
** is not changed but instead the prior value of that setting is written
965
** into the array entry, allowing the current retry settings to be
966
** interrogated.  The zDbName parameter is ignored.
967
**
968
** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
969
** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
970
** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
971
** write ahead log ([WAL file]) and shared memory
972
** files used for transaction control
973
** are automatically deleted when the latest connection to the database
974
** closes.  Setting persistent WAL mode causes those files to persist after
975
** close.  Persisting the files is useful when other processes that do not
976
** have write permission on the directory containing the database file want
977
** to read the database file, as the WAL and shared memory files must exist
978
** in order for the database to be readable.  The fourth parameter to
979
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
980
** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
981
** WAL mode.  If the integer is -1, then it is overwritten with the current
982
** WAL persistence setting.
983
**
984
** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
985
** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
986
** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
987
** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
988
** xDeviceCharacteristics methods. The fourth parameter to
989
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
990
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
991
** mode.  If the integer is -1, then it is overwritten with the current
992
** zero-damage mode setting.
993
**
994
** <li>[[SQLITE_FCNTL_OVERWRITE]]
995
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
996
** a write transaction to indicate that, unless it is rolled back for some
997
** reason, the entire database file will be overwritten by the current
998
** transaction. This is used by VACUUM operations.
999
**
1000
** <li>[[SQLITE_FCNTL_VFSNAME]]
1001
** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
1002
** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
1003
** final bottom-level VFS are written into memory obtained from
1004
** [sqlite3_malloc()] and the result is stored in the char* variable
1005
** that the fourth parameter of [sqlite3_file_control()] points to.
1006
** The caller is responsible for freeing the memory when done.  As with
1007
** all file-control actions, there is no guarantee that this will actually
1008
** do anything.  Callers should initialize the char* variable to a NULL
1009
** pointer in case this file-control is not implemented.  This file-control
1010
** is intended for diagnostic use only.
1011
**
1012
** <li>[[SQLITE_FCNTL_VFS_POINTER]]
1013
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
1014
** [VFSes] currently in use.  ^(The argument X in
1015
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
1016
** of type "[sqlite3_vfs] **".  This opcodes will set *X
1017
** to a pointer to the top-level VFS.)^
1018
** ^When there are multiple VFS shims in the stack, this opcode finds the
1019
** upper-most shim only.
1020
**
1021
** <li>[[SQLITE_FCNTL_PRAGMA]]
1022
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1023
** file control is sent to the open [sqlite3_file] object corresponding
1024
** to the database file to which the pragma statement refers. ^The argument
1025
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1026
** pointers to strings (char**) in which the second element of the array
1027
** is the name of the pragma and the third element is the argument to the
1028
** pragma or NULL if the pragma has no argument.  ^The handler for an
1029
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1030
** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1031
** or the equivalent and that string will become the result of the pragma or
1032
** the error message if the pragma fails. ^If the
1033
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1034
** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
1035
** file control returns [SQLITE_OK], then the parser assumes that the
1036
** VFS has handled the PRAGMA itself and the parser generates a no-op
1037
** prepared statement if result string is NULL, or that returns a copy
1038
** of the result string if the string is non-NULL.
1039
** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1040
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1041
** that the VFS encountered an error while handling the [PRAGMA] and the
1042
** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
1043
** file control occurs at the beginning of pragma statement analysis and so
1044
** it is able to override built-in [PRAGMA] statements.
1045
**
1046
** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1047
** ^The [SQLITE_FCNTL_BUSYHANDLER]
1048
** file-control may be invoked by SQLite on the database file handle
1049
** shortly after it is opened in order to provide a custom VFS with access
1050
** to the connection's busy-handler callback. The argument is of type (void**)
1051
** - an array of two (void *) values. The first (void *) actually points
1052
** to a function of type (int (*)(void *)). In order to invoke the connection's
1053
** busy-handler, this function should be invoked with the second (void *) in
1054
** the array as the only argument. If it returns non-zero, then the operation
1055
** should be retried. If it returns zero, the custom VFS should abandon the
1056
** current operation.
1057
**
1058
** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1059
** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1060
** to have SQLite generate a
1061
** temporary filename using the same algorithm that is followed to generate
1062
** temporary filenames for TEMP tables and other internal uses.  The
1063
** argument should be a char** which will be filled with the filename
1064
** written into memory obtained from [sqlite3_malloc()].  The caller should
1065
** invoke [sqlite3_free()] on the result to avoid a memory leak.
1066
**
1067
** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1068
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1069
** maximum number of bytes that will be used for memory-mapped I/O.
1070
** The argument is a pointer to a value of type sqlite3_int64 that
1071
** is an advisory maximum number of bytes in the file to memory map.  The
1072
** pointer is overwritten with the old value.  The limit is not changed if
1073
** the value originally pointed to is negative, and so the current limit
1074
** can be queried by passing in a pointer to a negative number.  This
1075
** file-control is used internally to implement [PRAGMA mmap_size].
1076
**
1077
** <li>[[SQLITE_FCNTL_TRACE]]
1078
** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1079
** to the VFS about what the higher layers of the SQLite stack are doing.
1080
** This file control is used by some VFS activity tracing [shims].
1081
** The argument is a zero-terminated string.  Higher layers in the
1082
** SQLite stack may generate instances of this file control if
1083
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1084
**
1085
** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1086
** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1087
** pointer to an integer and it writes a boolean into that integer depending
1088
** on whether or not the file has been renamed, moved, or deleted since it
1089
** was first opened.
1090
**
1091
** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
1092
** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
1093
** underlying native file handle associated with a file handle.  This file
1094
** control interprets its argument as a pointer to a native file handle and
1095
** writes the resulting value there.
1096
**
1097
** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1098
** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
1099
** opcode causes the xFileControl method to swap the file handle with the one
1100
** pointed to by the pArg argument.  This capability is used during testing
1101
** and only needs to be supported when SQLITE_TEST is defined.
1102
**
1103
** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1104
** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1105
** be advantageous to block on the next WAL lock if the lock is not immediately
1106
** available.  The WAL subsystem issues this signal during rare
1107
** circumstances in order to fix a problem with priority inversion.
1108
** Applications should <em>not</em> use this file-control.
1109
**
1110
** <li>[[SQLITE_FCNTL_ZIPVFS]]
1111
** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1112
** VFS should return SQLITE_NOTFOUND for this opcode.
1113
**
1114
** <li>[[SQLITE_FCNTL_RBU]]
1115
** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1116
** the RBU extension only.  All other VFS should return SQLITE_NOTFOUND for
1117
** this opcode.
1118
**
1119
** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1120
** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1121
** the file descriptor is placed in "batch write mode", which
1122
** means all subsequent write operations will be deferred and done
1123
** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].  Systems
1124
** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1125
** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1126
** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1127
** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1128
** no VFS interface calls on the same [sqlite3_file] file descriptor
1129
** except for calls to the xWrite method and the xFileControl method
1130
** with [SQLITE_FCNTL_SIZE_HINT].
1131
**
1132
** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1133
** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1134
** operations since the previous successful call to
1135
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1136
** This file control returns [SQLITE_OK] if and only if the writes were
1137
** all performed successfully and have been committed to persistent storage.
1138
** ^Regardless of whether or not it is successful, this file control takes
1139
** the file descriptor out of batch write mode so that all subsequent
1140
** write operations are independent.
1141
** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1142
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1143
**
1144
** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1145
** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1146
** operations since the previous successful call to
1147
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1148
** ^This file control takes the file descriptor out of batch write mode
1149
** so that all subsequent write operations are independent.
1150
** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1151
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1152
**
1153
** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
1154
** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS
1155
** to block for up to M milliseconds before failing when attempting to
1156
** obtain a file lock using the xLock or xShmLock methods of the VFS.
1157
** The parameter is a pointer to a 32-bit signed integer that contains
1158
** the value that M is to be set to. Before returning, the 32-bit signed
1159
** integer is overwritten with the previous value of M.
1160
**
1161
** <li>[[SQLITE_FCNTL_DATA_VERSION]]
1162
** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
1163
** a database file.  The argument is a pointer to a 32-bit unsigned integer.
1164
** The "data version" for the pager is written into the pointer.  The
1165
** "data version" changes whenever any change occurs to the corresponding
1166
** database file, either through SQL statements on the same database
1167
** connection or through transactions committed by separate database
1168
** connections possibly in other processes. The [sqlite3_total_changes()]
1169
** interface can be used to find if any database on the connection has changed,
1170
** but that interface responds to changes on TEMP as well as MAIN and does
1171
** not provide a mechanism to detect changes to MAIN only.  Also, the
1172
** [sqlite3_total_changes()] interface responds to internal changes only and
1173
** omits changes made by other database connections.  The
1174
** [PRAGMA data_version] command provides a mechanism to detect changes to
1175
** a single attached database that occur due to other database connections,
1176
** but omits changes implemented by the database connection on which it is
1177
** called.  This file control is the only mechanism to detect changes that
1178
** happen either internally or externally and that are associated with
1179
** a particular attached database.
1180
**
1181
** <li>[[SQLITE_FCNTL_CKPT_START]]
1182
** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint
1183
** in wal mode before the client starts to copy pages from the wal
1184
** file to the database file.
1185
**
1186
** <li>[[SQLITE_FCNTL_CKPT_DONE]]
1187
** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint
1188
** in wal mode after the client has finished copying pages from the wal
1189
** file to the database file, but before the *-shm file is updated to
1190
** record the fact that the pages have been checkpointed.
1191
**
1192
** <li>[[SQLITE_FCNTL_EXTERNAL_READER]]
1193
** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect
1194
** whether or not there is a database client in another process with a wal-mode
1195
** transaction open on the database or not. It is only available on unix.The
1196
** (void*) argument passed with this file-control should be a pointer to a
1197
** value of type (int). The integer value is set to 1 if the database is a wal
1198
** mode database and there exists at least one client in another process that
1199
** currently has an SQL transaction open on the database. It is set to 0 if
1200
** the database is not a wal-mode db, or if there is no such connection in any
1201
** other process. This opcode cannot be used to detect transactions opened
1202
** by clients within the current process, only within other processes.
1203
**
1204
** <li>[[SQLITE_FCNTL_CKSM_FILE]]
1205
** The [SQLITE_FCNTL_CKSM_FILE] opcode is for use internally by the
1206
** [checksum VFS shim] only.
1207
**
1208
** <li>[[SQLITE_FCNTL_RESET_CACHE]]
1209
** If there is currently no transaction open on the database, and the
1210
** database is not a temp db, then the [SQLITE_FCNTL_RESET_CACHE] file-control
1211
** purges the contents of the in-memory page cache. If there is an open
1212
** transaction, or if the db is a temp-db, this opcode is a no-op, not an error.
1213
** </ul>
1214
*/
1215
#define SQLITE_FCNTL_LOCKSTATE               1
1216
#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
1217
#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
1218
#define SQLITE_FCNTL_LAST_ERRNO              4
1219
#define SQLITE_FCNTL_SIZE_HINT               5
1220
#define SQLITE_FCNTL_CHUNK_SIZE              6
1221
#define SQLITE_FCNTL_FILE_POINTER            7
1222
#define SQLITE_FCNTL_SYNC_OMITTED            8
1223
#define SQLITE_FCNTL_WIN32_AV_RETRY          9
1224
#define SQLITE_FCNTL_PERSIST_WAL            10
1225
#define SQLITE_FCNTL_OVERWRITE              11
1226
#define SQLITE_FCNTL_VFSNAME                12
1227
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
1228
#define SQLITE_FCNTL_PRAGMA                 14
1229
#define SQLITE_FCNTL_BUSYHANDLER            15
1230
#define SQLITE_FCNTL_TEMPFILENAME           16
1231
#define SQLITE_FCNTL_MMAP_SIZE              18
1232
#define SQLITE_FCNTL_TRACE                  19
1233
#define SQLITE_FCNTL_HAS_MOVED              20
1234
#define SQLITE_FCNTL_SYNC                   21
1235
#define SQLITE_FCNTL_COMMIT_PHASETWO        22
1236
#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
1237
#define SQLITE_FCNTL_WAL_BLOCK              24
1238
#define SQLITE_FCNTL_ZIPVFS                 25
1239
#define SQLITE_FCNTL_RBU                    26
1240
#define SQLITE_FCNTL_VFS_POINTER            27
1241
#define SQLITE_FCNTL_JOURNAL_POINTER        28
1242
#define SQLITE_FCNTL_WIN32_GET_HANDLE       29
1243
#define SQLITE_FCNTL_PDB                    30
1244
#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE     31
1245
#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE    32
1246
#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE  33
1247
#define SQLITE_FCNTL_LOCK_TIMEOUT           34
1248
#define SQLITE_FCNTL_DATA_VERSION           35
1249
#define SQLITE_FCNTL_SIZE_LIMIT             36
1250
#define SQLITE_FCNTL_CKPT_DONE              37
1251
#define SQLITE_FCNTL_RESERVE_BYTES          38
1252
#define SQLITE_FCNTL_CKPT_START             39
1253
#define SQLITE_FCNTL_EXTERNAL_READER        40
1254
#define SQLITE_FCNTL_CKSM_FILE              41
1255
#define SQLITE_FCNTL_RESET_CACHE            42
1256
1257
/* deprecated names */
1258
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
1259
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
1260
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO
1261
1262
1263
/*
1264
** CAPI3REF: Mutex Handle
1265
**
1266
** The mutex module within SQLite defines [sqlite3_mutex] to be an
1267
** abstract type for a mutex object.  The SQLite core never looks
1268
** at the internal representation of an [sqlite3_mutex].  It only
1269
** deals with pointers to the [sqlite3_mutex] object.
1270
**
1271
** Mutexes are created using [sqlite3_mutex_alloc()].
1272
*/
1273
typedef struct sqlite3_mutex sqlite3_mutex;
1274
1275
/*
1276
** CAPI3REF: Loadable Extension Thunk
1277
**
1278
** A pointer to the opaque sqlite3_api_routines structure is passed as
1279
** the third parameter to entry points of [loadable extensions].  This
1280
** structure must be typedefed in order to work around compiler warnings
1281
** on some platforms.
1282
*/
1283
typedef struct sqlite3_api_routines sqlite3_api_routines;
1284
1285
/*
1286
** CAPI3REF: File Name
1287
**
1288
** Type [sqlite3_filename] is used by SQLite to pass filenames to the
1289
** xOpen method of a [VFS]. It may be cast to (const char*) and treated
1290
** as a normal, nul-terminated, UTF-8 buffer containing the filename, but
1291
** may also be passed to special APIs such as:
1292
**
1293
** <ul>
1294
** <li>  sqlite3_filename_database()
1295
** <li>  sqlite3_filename_journal()
1296
** <li>  sqlite3_filename_wal()
1297
** <li>  sqlite3_uri_parameter()
1298
** <li>  sqlite3_uri_boolean()
1299
** <li>  sqlite3_uri_int64()
1300
** <li>  sqlite3_uri_key()
1301
** </ul>
1302
*/
1303
typedef const char *sqlite3_filename;
1304
1305
/*
1306
** CAPI3REF: OS Interface Object
1307
**
1308
** An instance of the sqlite3_vfs object defines the interface between
1309
** the SQLite core and the underlying operating system.  The "vfs"
1310
** in the name of the object stands for "virtual file system".  See
1311
** the [VFS | VFS documentation] for further information.
1312
**
1313
** The VFS interface is sometimes extended by adding new methods onto
1314
** the end.  Each time such an extension occurs, the iVersion field
1315
** is incremented.  The iVersion value started out as 1 in
1316
** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
1317
** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
1318
** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6].  Additional fields
1319
** may be appended to the sqlite3_vfs object and the iVersion value
1320
** may increase again in future versions of SQLite.
1321
** Note that due to an oversight, the structure
1322
** of the sqlite3_vfs object changed in the transition from
1323
** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
1324
** and yet the iVersion field was not increased.
1325
**
1326
** The szOsFile field is the size of the subclassed [sqlite3_file]
1327
** structure used by this VFS.  mxPathname is the maximum length of
1328
** a pathname in this VFS.
1329
**
1330
** Registered sqlite3_vfs objects are kept on a linked list formed by
1331
** the pNext pointer.  The [sqlite3_vfs_register()]
1332
** and [sqlite3_vfs_unregister()] interfaces manage this list
1333
** in a thread-safe way.  The [sqlite3_vfs_find()] interface
1334
** searches the list.  Neither the application code nor the VFS
1335
** implementation should use the pNext pointer.
1336
**
1337
** The pNext field is the only field in the sqlite3_vfs
1338
** structure that SQLite will ever modify.  SQLite will only access
1339
** or modify this field while holding a particular static mutex.
1340
** The application should never modify anything within the sqlite3_vfs
1341
** object once the object has been registered.
1342
**
1343
** The zName field holds the name of the VFS module.  The name must
1344
** be unique across all VFS modules.
1345
**
1346
** [[sqlite3_vfs.xOpen]]
1347
** ^SQLite guarantees that the zFilename parameter to xOpen
1348
** is either a NULL pointer or string obtained
1349
** from xFullPathname() with an optional suffix added.
1350
** ^If a suffix is added to the zFilename parameter, it will
1351
** consist of a single "-" character followed by no more than
1352
** 11 alphanumeric and/or "-" characters.
1353
** ^SQLite further guarantees that
1354
** the string will be valid and unchanged until xClose() is
1355
** called. Because of the previous sentence,
1356
** the [sqlite3_file] can safely store a pointer to the
1357
** filename if it needs to remember the filename for some reason.
1358
** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1359
** must invent its own temporary name for the file.  ^Whenever the
1360
** xFilename parameter is NULL it will also be the case that the
1361
** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1362
**
1363
** The flags argument to xOpen() includes all bits set in
1364
** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
1365
** or [sqlite3_open16()] is used, then flags includes at least
1366
** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1367
** If xOpen() opens a file read-only then it sets *pOutFlags to
1368
** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
1369
**
1370
** ^(SQLite will also add one of the following flags to the xOpen()
1371
** call, depending on the object being opened:
1372
**
1373
** <ul>
1374
** <li>  [SQLITE_OPEN_MAIN_DB]
1375
** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
1376
** <li>  [SQLITE_OPEN_TEMP_DB]
1377
** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
1378
** <li>  [SQLITE_OPEN_TRANSIENT_DB]
1379
** <li>  [SQLITE_OPEN_SUBJOURNAL]
1380
** <li>  [SQLITE_OPEN_SUPER_JOURNAL]
1381
** <li>  [SQLITE_OPEN_WAL]
1382
** </ul>)^
1383
**
1384
** The file I/O implementation can use the object type flags to
1385
** change the way it deals with files.  For example, an application
1386
** that does not care about crash recovery or rollback might make
1387
** the open of a journal file a no-op.  Writes to this journal would
1388
** also be no-ops, and any attempt to read the journal would return
1389
** SQLITE_IOERR.  Or the implementation might recognize that a database
1390
** file will be doing page-aligned sector reads and writes in a random
1391
** order and set up its I/O subsystem accordingly.
1392
**
1393
** SQLite might also add one of the following flags to the xOpen method:
1394
**
1395
** <ul>
1396
** <li> [SQLITE_OPEN_DELETEONCLOSE]
1397
** <li> [SQLITE_OPEN_EXCLUSIVE]
1398
** </ul>
1399
**
1400
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1401
** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
1402
** will be set for TEMP databases and their journals, transient
1403
** databases, and subjournals.
1404
**
1405
** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1406
** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1407
** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1408
** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1409
** SQLITE_OPEN_CREATE, is used to indicate that file should always
1410
** be created, and that it is an error if it already exists.
1411
** It is <i>not</i> used to indicate the file should be opened
1412
** for exclusive access.
1413
**
1414
** ^At least szOsFile bytes of memory are allocated by SQLite
1415
** to hold the [sqlite3_file] structure passed as the third
1416
** argument to xOpen.  The xOpen method does not have to
1417
** allocate the structure; it should just fill it in.  Note that
1418
** the xOpen method must set the sqlite3_file.pMethods to either
1419
** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
1420
** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
1421
** element will be valid after xOpen returns regardless of the success
1422
** or failure of the xOpen call.
1423
**
1424
** [[sqlite3_vfs.xAccess]]
1425
** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1426
** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1427
** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1428
** to test whether a file is at least readable.  The SQLITE_ACCESS_READ
1429
** flag is never actually used and is not implemented in the built-in
1430
** VFSes of SQLite.  The file is named by the second argument and can be a
1431
** directory. The xAccess method returns [SQLITE_OK] on success or some
1432
** non-zero error code if there is an I/O error or if the name of
1433
** the file given in the second argument is illegal.  If SQLITE_OK
1434
** is returned, then non-zero or zero is written into *pResOut to indicate
1435
** whether or not the file is accessible.
1436
**
1437
** ^SQLite will always allocate at least mxPathname+1 bytes for the
1438
** output buffer xFullPathname.  The exact size of the output buffer
1439
** is also passed as a parameter to both  methods. If the output buffer
1440
** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1441
** handled as a fatal error by SQLite, vfs implementations should endeavor
1442
** to prevent this by setting mxPathname to a sufficiently large value.
1443
**
1444
** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1445
** interfaces are not strictly a part of the filesystem, but they are
1446
** included in the VFS structure for completeness.
1447
** The xRandomness() function attempts to return nBytes bytes
1448
** of good-quality randomness into zOut.  The return value is
1449
** the actual number of bytes of randomness obtained.
1450
** The xSleep() method causes the calling thread to sleep for at
1451
** least the number of microseconds given.  ^The xCurrentTime()
1452
** method returns a Julian Day Number for the current date and time as
1453
** a floating point value.
1454
** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1455
** Day Number multiplied by 86400000 (the number of milliseconds in
1456
** a 24-hour day).
1457
** ^SQLite will use the xCurrentTimeInt64() method to get the current
1458
** date and time if that method is available (if iVersion is 2 or
1459
** greater and the function pointer is not NULL) and will fall back
1460
** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1461
**
1462
** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1463
** are not used by the SQLite core.  These optional interfaces are provided
1464
** by some VFSes to facilitate testing of the VFS code. By overriding
1465
** system calls with functions under its control, a test program can
1466
** simulate faults and error conditions that would otherwise be difficult
1467
** or impossible to induce.  The set of system calls that can be overridden
1468
** varies from one VFS to another, and from one version of the same VFS to the
1469
** next.  Applications that use these interfaces must be prepared for any
1470
** or all of these interfaces to be NULL or for their behavior to change
1471
** from one release to the next.  Applications must not attempt to access
1472
** any of these methods if the iVersion of the VFS is less than 3.
1473
*/
1474
typedef struct sqlite3_vfs sqlite3_vfs;
1475
typedef void (*sqlite3_syscall_ptr)(void);
1476
struct sqlite3_vfs {
1477
  int iVersion;            /* Structure version number (currently 3) */
1478
  int szOsFile;            /* Size of subclassed sqlite3_file */
1479
  int mxPathname;          /* Maximum file pathname length */
1480
  sqlite3_vfs *pNext;      /* Next registered VFS */
1481
  const char *zName;       /* Name of this virtual file system */
1482
  void *pAppData;          /* Pointer to application-specific data */
1483
  int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*,
1484
               int flags, int *pOutFlags);
1485
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1486
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1487
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1488
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1489
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1490
  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1491
  void (*xDlClose)(sqlite3_vfs*, void*);
1492
  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1493
  int (*xSleep)(sqlite3_vfs*, int microseconds);
1494
  int (*xCurrentTime)(sqlite3_vfs*, double*);
1495
  int (*xGetLastError)(sqlite3_vfs*, int, char *);
1496
  /*
1497
  ** The methods above are in version 1 of the sqlite_vfs object
1498
  ** definition.  Those that follow are added in version 2 or later
1499
  */
1500
  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1501
  /*
1502
  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1503
  ** Those below are for version 3 and greater.
1504
  */
1505
  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1506
  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1507
  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1508
  /*
1509
  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1510
  ** New fields may be appended in future versions.  The iVersion
1511
  ** value will increment whenever this happens.
1512
  */
1513
};
1514
1515
/*
1516
** CAPI3REF: Flags for the xAccess VFS method
1517
**
1518
** These integer constants can be used as the third parameter to
1519
** the xAccess method of an [sqlite3_vfs] object.  They determine
1520
** what kind of permissions the xAccess method is looking for.
1521
** With SQLITE_ACCESS_EXISTS, the xAccess method
1522
** simply checks whether the file exists.
1523
** With SQLITE_ACCESS_READWRITE, the xAccess method
1524
** checks whether the named directory is both readable and writable
1525
** (in other words, if files can be added, removed, and renamed within
1526
** the directory).
1527
** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1528
** [temp_store_directory pragma], though this could change in a future
1529
** release of SQLite.
1530
** With SQLITE_ACCESS_READ, the xAccess method
1531
** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
1532
** currently unused, though it might be used in a future release of
1533
** SQLite.
1534
*/
1535
#define SQLITE_ACCESS_EXISTS    0
1536
#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
1537
#define SQLITE_ACCESS_READ      2   /* Unused */
1538
1539
/*
1540
** CAPI3REF: Flags for the xShmLock VFS method
1541
**
1542
** These integer constants define the various locking operations
1543
** allowed by the xShmLock method of [sqlite3_io_methods].  The
1544
** following are the only legal combinations of flags to the
1545
** xShmLock method:
1546
**
1547
** <ul>
1548
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1549
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1550
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1551
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1552
** </ul>
1553
**
1554
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1555
** was given on the corresponding lock.
1556
**
1557
** The xShmLock method can transition between unlocked and SHARED or
1558
** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
1559
** and EXCLUSIVE.
1560
*/
1561
#define SQLITE_SHM_UNLOCK       1
1562
#define SQLITE_SHM_LOCK         2
1563
#define SQLITE_SHM_SHARED       4
1564
#define SQLITE_SHM_EXCLUSIVE    8
1565
1566
/*
1567
** CAPI3REF: Maximum xShmLock index
1568
**
1569
** The xShmLock method on [sqlite3_io_methods] may use values
1570
** between 0 and this upper bound as its "offset" argument.
1571
** The SQLite core will never attempt to acquire or release a
1572
** lock outside of this range
1573
*/
1574
#define SQLITE_SHM_NLOCK        8
1575
1576
1577
/*
1578
** CAPI3REF: Initialize The SQLite Library
1579
**
1580
** ^The sqlite3_initialize() routine initializes the
1581
** SQLite library.  ^The sqlite3_shutdown() routine
1582
** deallocates any resources that were allocated by sqlite3_initialize().
1583
** These routines are designed to aid in process initialization and
1584
** shutdown on embedded systems.  Workstation applications using
1585
** SQLite normally do not need to invoke either of these routines.
1586
**
1587
** A call to sqlite3_initialize() is an "effective" call if it is
1588
** the first time sqlite3_initialize() is invoked during the lifetime of
1589
** the process, or if it is the first time sqlite3_initialize() is invoked
1590
** following a call to sqlite3_shutdown().  ^(Only an effective call
1591
** of sqlite3_initialize() does any initialization.  All other calls
1592
** are harmless no-ops.)^
1593
**
1594
** A call to sqlite3_shutdown() is an "effective" call if it is the first
1595
** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
1596
** an effective call to sqlite3_shutdown() does any deinitialization.
1597
** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1598
**
1599
** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1600
** is not.  The sqlite3_shutdown() interface must only be called from a
1601
** single thread.  All open [database connections] must be closed and all
1602
** other SQLite resources must be deallocated prior to invoking
1603
** sqlite3_shutdown().
1604
**
1605
** Among other things, ^sqlite3_initialize() will invoke
1606
** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
1607
** will invoke sqlite3_os_end().
1608
**
1609
** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1610
** ^If for some reason, sqlite3_initialize() is unable to initialize
1611
** the library (perhaps it is unable to allocate a needed resource such
1612
** as a mutex) it returns an [error code] other than [SQLITE_OK].
1613
**
1614
** ^The sqlite3_initialize() routine is called internally by many other
1615
** SQLite interfaces so that an application usually does not need to
1616
** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
1617
** calls sqlite3_initialize() so the SQLite library will be automatically
1618
** initialized when [sqlite3_open()] is called if it has not be initialized
1619
** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1620
** compile-time option, then the automatic calls to sqlite3_initialize()
1621
** are omitted and the application must call sqlite3_initialize() directly
1622
** prior to using any other SQLite interface.  For maximum portability,
1623
** it is recommended that applications always invoke sqlite3_initialize()
1624
** directly prior to using any other SQLite interface.  Future releases
1625
** of SQLite may require this.  In other words, the behavior exhibited
1626
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1627
** default behavior in some future release of SQLite.
1628
**
1629
** The sqlite3_os_init() routine does operating-system specific
1630
** initialization of the SQLite library.  The sqlite3_os_end()
1631
** routine undoes the effect of sqlite3_os_init().  Typical tasks
1632
** performed by these routines include allocation or deallocation
1633
** of static resources, initialization of global variables,
1634
** setting up a default [sqlite3_vfs] module, or setting up
1635
** a default configuration using [sqlite3_config()].
1636
**
1637
** The application should never invoke either sqlite3_os_init()
1638
** or sqlite3_os_end() directly.  The application should only invoke
1639
** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
1640
** interface is called automatically by sqlite3_initialize() and
1641
** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
1642
** implementations for sqlite3_os_init() and sqlite3_os_end()
1643
** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1644
** When [custom builds | built for other platforms]
1645
** (using the [SQLITE_OS_OTHER=1] compile-time
1646
** option) the application must supply a suitable implementation for
1647
** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
1648
** implementation of sqlite3_os_init() or sqlite3_os_end()
1649
** must return [SQLITE_OK] on success and some other [error code] upon
1650
** failure.
1651
*/
1652
SQLITE_API int sqlite3_initialize(void);
1653
SQLITE_API int sqlite3_shutdown(void);
1654
SQLITE_API int sqlite3_os_init(void);
1655
SQLITE_API int sqlite3_os_end(void);
1656
1657
/*
1658
** CAPI3REF: Configuring The SQLite Library
1659
**
1660
** The sqlite3_config() interface is used to make global configuration
1661
** changes to SQLite in order to tune SQLite to the specific needs of
1662
** the application.  The default configuration is recommended for most
1663
** applications and so this routine is usually not necessary.  It is
1664
** provided to support rare applications with unusual needs.
1665
**
1666
** <b>The sqlite3_config() interface is not threadsafe. The application
1667
** must ensure that no other SQLite interfaces are invoked by other
1668
** threads while sqlite3_config() is running.</b>
1669
**
1670
** The first argument to sqlite3_config() is an integer
1671
** [configuration option] that determines
1672
** what property of SQLite is to be configured.  Subsequent arguments
1673
** vary depending on the [configuration option]
1674
** in the first argument.
1675
**
1676
** For most configuration options, the sqlite3_config() interface
1677
** may only be invoked prior to library initialization using
1678
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1679
** The exceptional configuration options that may be invoked at any time
1680
** are called "anytime configuration options".
1681
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1682
** [sqlite3_shutdown()] with a first argument that is not an anytime
1683
** configuration option, then the sqlite3_config() call will return SQLITE_MISUSE.
1684
** Note, however, that ^sqlite3_config() can be called as part of the
1685
** implementation of an application-defined [sqlite3_os_init()].
1686
**
1687
** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1688
** ^If the option is unknown or SQLite is unable to set the option
1689
** then this routine returns a non-zero [error code].
1690
*/
1691
SQLITE_API int sqlite3_config(int, ...);
1692
1693
/*
1694
** CAPI3REF: Configure database connections
1695
** METHOD: sqlite3
1696
**
1697
** The sqlite3_db_config() interface is used to make configuration
1698
** changes to a [database connection].  The interface is similar to
1699
** [sqlite3_config()] except that the changes apply to a single
1700
** [database connection] (specified in the first argument).
1701
**
1702
** The second argument to sqlite3_db_config(D,V,...)  is the
1703
** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1704
** that indicates what aspect of the [database connection] is being configured.
1705
** Subsequent arguments vary depending on the configuration verb.
1706
**
1707
** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1708
** the call is considered successful.
1709
*/
1710
SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1711
1712
/*
1713
** CAPI3REF: Memory Allocation Routines
1714
**
1715
** An instance of this object defines the interface between SQLite
1716
** and low-level memory allocation routines.
1717
**
1718
** This object is used in only one place in the SQLite interface.
1719
** A pointer to an instance of this object is the argument to
1720
** [sqlite3_config()] when the configuration option is
1721
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1722
** By creating an instance of this object
1723
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1724
** during configuration, an application can specify an alternative
1725
** memory allocation subsystem for SQLite to use for all of its
1726
** dynamic memory needs.
1727
**
1728
** Note that SQLite comes with several [built-in memory allocators]
1729
** that are perfectly adequate for the overwhelming majority of applications
1730
** and that this object is only useful to a tiny minority of applications
1731
** with specialized memory allocation requirements.  This object is
1732
** also used during testing of SQLite in order to specify an alternative
1733
** memory allocator that simulates memory out-of-memory conditions in
1734
** order to verify that SQLite recovers gracefully from such
1735
** conditions.
1736
**
1737
** The xMalloc, xRealloc, and xFree methods must work like the
1738
** malloc(), realloc() and free() functions from the standard C library.
1739
** ^SQLite guarantees that the second argument to
1740
** xRealloc is always a value returned by a prior call to xRoundup.
1741
**
1742
** xSize should return the allocated size of a memory allocation
1743
** previously obtained from xMalloc or xRealloc.  The allocated size
1744
** is always at least as big as the requested size but may be larger.
1745
**
1746
** The xRoundup method returns what would be the allocated size of
1747
** a memory allocation given a particular requested size.  Most memory
1748
** allocators round up memory allocations at least to the next multiple
1749
** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1750
** Every memory allocation request coming in through [sqlite3_malloc()]
1751
** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0,
1752
** that causes the corresponding memory allocation to fail.
1753
**
1754
** The xInit method initializes the memory allocator.  For example,
1755
** it might allocate any required mutexes or initialize internal data
1756
** structures.  The xShutdown method is invoked (indirectly) by
1757
** [sqlite3_shutdown()] and should deallocate any resources acquired
1758
** by xInit.  The pAppData pointer is used as the only parameter to
1759
** xInit and xShutdown.
1760
**
1761
** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes
1762
** the xInit method, so the xInit method need not be threadsafe.  The
1763
** xShutdown method is only called from [sqlite3_shutdown()] so it does
1764
** not need to be threadsafe either.  For all other methods, SQLite
1765
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1766
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1767
** it is by default) and so the methods are automatically serialized.
1768
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1769
** methods must be threadsafe or else make their own arrangements for
1770
** serialization.
1771
**
1772
** SQLite will never invoke xInit() more than once without an intervening
1773
** call to xShutdown().
1774
*/
1775
typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1776
struct sqlite3_mem_methods {
1777
  void *(*xMalloc)(int);         /* Memory allocation function */
1778
  void (*xFree)(void*);          /* Free a prior allocation */
1779
  void *(*xRealloc)(void*,int);  /* Resize an allocation */
1780
  int (*xSize)(void*);           /* Return the size of an allocation */
1781
  int (*xRoundup)(int);          /* Round up request size to allocation size */
1782
  int (*xInit)(void*);           /* Initialize the memory allocator */
1783
  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
1784
  void *pAppData;                /* Argument to xInit() and xShutdown() */
1785
};
1786
1787
/*
1788
** CAPI3REF: Configuration Options
1789
** KEYWORDS: {configuration option}
1790
**
1791
** These constants are the available integer configuration options that
1792
** can be passed as the first argument to the [sqlite3_config()] interface.
1793
**
1794
** Most of the configuration options for sqlite3_config()
1795
** will only work if invoked prior to [sqlite3_initialize()] or after
1796
** [sqlite3_shutdown()].  The few exceptions to this rule are called
1797
** "anytime configuration options".
1798
** ^Calling [sqlite3_config()] with a first argument that is not an
1799
** anytime configuration option in between calls to [sqlite3_initialize()] and
1800
** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE.
1801
**
1802
** The set of anytime configuration options can change (by insertions
1803
** and/or deletions) from one release of SQLite to the next.
1804
** As of SQLite version 3.42.0, the complete set of anytime configuration
1805
** options is:
1806
** <ul>
1807
** <li> SQLITE_CONFIG_LOG
1808
** <li> SQLITE_CONFIG_PCACHE_HDRSZ
1809
** </ul>
1810
**
1811
** New configuration options may be added in future releases of SQLite.
1812
** Existing configuration options might be discontinued.  Applications
1813
** should check the return code from [sqlite3_config()] to make sure that
1814
** the call worked.  The [sqlite3_config()] interface will return a
1815
** non-zero [error code] if a discontinued or unsupported configuration option
1816
** is invoked.
1817
**
1818
** <dl>
1819
** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1820
** <dd>There are no arguments to this option.  ^This option sets the
1821
** [threading mode] to Single-thread.  In other words, it disables
1822
** all mutexing and puts SQLite into a mode where it can only be used
1823
** by a single thread.   ^If SQLite is compiled with
1824
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1825
** it is not possible to change the [threading mode] from its default
1826
** value of Single-thread and so [sqlite3_config()] will return
1827
** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1828
** configuration option.</dd>
1829
**
1830
** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1831
** <dd>There are no arguments to this option.  ^This option sets the
1832
** [threading mode] to Multi-thread.  In other words, it disables
1833
** mutexing on [database connection] and [prepared statement] objects.
1834
** The application is responsible for serializing access to
1835
** [database connections] and [prepared statements].  But other mutexes
1836
** are enabled so that SQLite will be safe to use in a multi-threaded
1837
** environment as long as no two threads attempt to use the same
1838
** [database connection] at the same time.  ^If SQLite is compiled with
1839
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1840
** it is not possible to set the Multi-thread [threading mode] and
1841
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1842
** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1843
**
1844
** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1845
** <dd>There are no arguments to this option.  ^This option sets the
1846
** [threading mode] to Serialized. In other words, this option enables
1847
** all mutexes including the recursive
1848
** mutexes on [database connection] and [prepared statement] objects.
1849
** In this mode (which is the default when SQLite is compiled with
1850
** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1851
** to [database connections] and [prepared statements] so that the
1852
** application is free to use the same [database connection] or the
1853
** same [prepared statement] in different threads at the same time.
1854
** ^If SQLite is compiled with
1855
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1856
** it is not possible to set the Serialized [threading mode] and
1857
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1858
** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1859
**
1860
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1861
** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1862
** a pointer to an instance of the [sqlite3_mem_methods] structure.
1863
** The argument specifies
1864
** alternative low-level memory allocation routines to be used in place of
1865
** the memory allocation routines built into SQLite.)^ ^SQLite makes
1866
** its own private copy of the content of the [sqlite3_mem_methods] structure
1867
** before the [sqlite3_config()] call returns.</dd>
1868
**
1869
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1870
** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1871
** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1872
** The [sqlite3_mem_methods]
1873
** structure is filled with the currently defined memory allocation routines.)^
1874
** This option can be used to overload the default memory allocation
1875
** routines with a wrapper that simulations memory allocation failure or
1876
** tracks memory usage, for example. </dd>
1877
**
1878
** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
1879
** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
1880
** type int, interpreted as a boolean, which if true provides a hint to
1881
** SQLite that it should avoid large memory allocations if possible.
1882
** SQLite will run faster if it is free to make large memory allocations,
1883
** but some application might prefer to run slower in exchange for
1884
** guarantees about memory fragmentation that are possible if large
1885
** allocations are avoided.  This hint is normally off.
1886
** </dd>
1887
**
1888
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1889
** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1890
** interpreted as a boolean, which enables or disables the collection of
1891
** memory allocation statistics. ^(When memory allocation statistics are
1892
** disabled, the following SQLite interfaces become non-operational:
1893
**   <ul>
1894
**   <li> [sqlite3_hard_heap_limit64()]
1895
**   <li> [sqlite3_memory_used()]
1896
**   <li> [sqlite3_memory_highwater()]
1897
**   <li> [sqlite3_soft_heap_limit64()]
1898
**   <li> [sqlite3_status64()]
1899
**   </ul>)^
1900
** ^Memory allocation statistics are enabled by default unless SQLite is
1901
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1902
** allocation statistics are disabled by default.
1903
** </dd>
1904
**
1905
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1906
** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1907
** </dd>
1908
**
1909
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1910
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1911
** that SQLite can use for the database page cache with the default page
1912
** cache implementation.
1913
** This configuration option is a no-op if an application-defined page
1914
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1915
** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1916
** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1917
** and the number of cache lines (N).
1918
** The sz argument should be the size of the largest database page
1919
** (a power of two between 512 and 65536) plus some extra bytes for each
1920
** page header.  ^The number of extra bytes needed by the page header
1921
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1922
** ^It is harmless, apart from the wasted memory,
1923
** for the sz parameter to be larger than necessary.  The pMem
1924
** argument must be either a NULL pointer or a pointer to an 8-byte
1925
** aligned block of memory of at least sz*N bytes, otherwise
1926
** subsequent behavior is undefined.
1927
** ^When pMem is not NULL, SQLite will strive to use the memory provided
1928
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1929
** a page cache line is larger than sz bytes or if all of the pMem buffer
1930
** is exhausted.
1931
** ^If pMem is NULL and N is non-zero, then each database connection
1932
** does an initial bulk allocation for page cache memory
1933
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1934
** of -1024*N bytes if N is negative, . ^If additional
1935
** page cache memory is needed beyond what is provided by the initial
1936
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1937
** additional cache line. </dd>
1938
**
1939
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1940
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1941
** that SQLite will use for all of its dynamic memory allocation needs
1942
** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1943
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1944
** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1945
** [SQLITE_ERROR] if invoked otherwise.
1946
** ^There are three arguments to SQLITE_CONFIG_HEAP:
1947
** An 8-byte aligned pointer to the memory,
1948
** the number of bytes in the memory buffer, and the minimum allocation size.
1949
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1950
** to using its default memory allocator (the system malloc() implementation),
1951
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
1952
** memory pointer is not NULL then the alternative memory
1953
** allocator is engaged to handle all of SQLites memory allocation needs.
1954
** The first pointer (the memory pointer) must be aligned to an 8-byte
1955
** boundary or subsequent behavior of SQLite will be undefined.
1956
** The minimum allocation size is capped at 2**12. Reasonable values
1957
** for the minimum allocation size are 2**5 through 2**8.</dd>
1958
**
1959
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1960
** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1961
** pointer to an instance of the [sqlite3_mutex_methods] structure.
1962
** The argument specifies alternative low-level mutex routines to be used
1963
** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
1964
** the content of the [sqlite3_mutex_methods] structure before the call to
1965
** [sqlite3_config()] returns. ^If SQLite is compiled with
1966
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1967
** the entire mutexing subsystem is omitted from the build and hence calls to
1968
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1969
** return [SQLITE_ERROR].</dd>
1970
**
1971
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1972
** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1973
** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
1974
** [sqlite3_mutex_methods]
1975
** structure is filled with the currently defined mutex routines.)^
1976
** This option can be used to overload the default mutex allocation
1977
** routines with a wrapper used to track mutex usage for performance
1978
** profiling or testing, for example.   ^If SQLite is compiled with
1979
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1980
** the entire mutexing subsystem is omitted from the build and hence calls to
1981
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1982
** return [SQLITE_ERROR].</dd>
1983
**
1984
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1985
** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1986
** the default size of lookaside memory on each [database connection].
1987
** The first argument is the
1988
** size of each lookaside buffer slot and the second is the number of
1989
** slots allocated to each database connection.)^  ^(SQLITE_CONFIG_LOOKASIDE
1990
** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1991
** option to [sqlite3_db_config()] can be used to change the lookaside
1992
** configuration on individual connections.)^ </dd>
1993
**
1994
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1995
** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
1996
** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
1997
** the interface to a custom page cache implementation.)^
1998
** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1999
**
2000
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
2001
** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
2002
** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
2003
** the current page cache implementation into that object.)^ </dd>
2004
**
2005
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
2006
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
2007
** global [error log].
2008
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
2009
** function with a call signature of void(*)(void*,int,const char*),
2010
** and a pointer to void. ^If the function pointer is not NULL, it is
2011
** invoked by [sqlite3_log()] to process each logging event.  ^If the
2012
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
2013
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
2014
** passed through as the first parameter to the application-defined logger
2015
** function whenever that function is invoked.  ^The second parameter to
2016
** the logger function is a copy of the first parameter to the corresponding
2017
** [sqlite3_log()] call and is intended to be a [result code] or an
2018
** [extended result code].  ^The third parameter passed to the logger is
2019
** log message after formatting via [sqlite3_snprintf()].
2020
** The SQLite logging interface is not reentrant; the logger function
2021
** supplied by the application must not invoke any SQLite interface.
2022
** In a multi-threaded application, the application-defined logger
2023
** function must be threadsafe. </dd>
2024
**
2025
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
2026
** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
2027
** If non-zero, then URI handling is globally enabled. If the parameter is zero,
2028
** then URI handling is globally disabled.)^ ^If URI handling is globally
2029
** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
2030
** [sqlite3_open16()] or
2031
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
2032
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
2033
** connection is opened. ^If it is globally disabled, filenames are
2034
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
2035
** database connection is opened. ^(By default, URI handling is globally
2036
** disabled. The default value may be changed by compiling with the
2037
** [SQLITE_USE_URI] symbol defined.)^
2038
**
2039
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
2040
** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
2041
** argument which is interpreted as a boolean in order to enable or disable
2042
** the use of covering indices for full table scans in the query optimizer.
2043
** ^The default setting is determined
2044
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
2045
** if that compile-time option is omitted.
2046
** The ability to disable the use of covering indices for full table scans
2047
** is because some incorrectly coded legacy applications might malfunction
2048
** when the optimization is enabled.  Providing the ability to
2049
** disable the optimization allows the older, buggy application code to work
2050
** without change even with newer versions of SQLite.
2051
**
2052
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
2053
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
2054
** <dd> These options are obsolete and should not be used by new code.
2055
** They are retained for backwards compatibility but are now no-ops.
2056
** </dd>
2057
**
2058
** [[SQLITE_CONFIG_SQLLOG]]
2059
** <dt>SQLITE_CONFIG_SQLLOG
2060
** <dd>This option is only available if sqlite is compiled with the
2061
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
2062
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
2063
** The second should be of type (void*). The callback is invoked by the library
2064
** in three separate circumstances, identified by the value passed as the
2065
** fourth parameter. If the fourth parameter is 0, then the database connection
2066
** passed as the second argument has just been opened. The third argument
2067
** points to a buffer containing the name of the main database file. If the
2068
** fourth parameter is 1, then the SQL statement that the third parameter
2069
** points to has just been executed. Or, if the fourth parameter is 2, then
2070
** the connection being passed as the second parameter is being closed. The
2071
** third parameter is passed NULL In this case.  An example of using this
2072
** configuration option can be seen in the "test_sqllog.c" source file in
2073
** the canonical SQLite source tree.</dd>
2074
**
2075
** [[SQLITE_CONFIG_MMAP_SIZE]]
2076
** <dt>SQLITE_CONFIG_MMAP_SIZE
2077
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
2078
** that are the default mmap size limit (the default setting for
2079
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
2080
** ^The default setting can be overridden by each database connection using
2081
** either the [PRAGMA mmap_size] command, or by using the
2082
** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
2083
** will be silently truncated if necessary so that it does not exceed the
2084
** compile-time maximum mmap size set by the
2085
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
2086
** ^If either argument to this option is negative, then that argument is
2087
** changed to its compile-time default.
2088
**
2089
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
2090
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
2091
** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
2092
** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
2093
** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
2094
** that specifies the maximum size of the created heap.
2095
**
2096
** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
2097
** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
2098
** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
2099
** is a pointer to an integer and writes into that integer the number of extra
2100
** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
2101
** The amount of extra space required can change depending on the compiler,
2102
** target platform, and SQLite version.
2103
**
2104
** [[SQLITE_CONFIG_PMASZ]]
2105
** <dt>SQLITE_CONFIG_PMASZ
2106
** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
2107
** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
2108
** sorter to that integer.  The default minimum PMA Size is set by the
2109
** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
2110
** to help with sort operations when multithreaded sorting
2111
** is enabled (using the [PRAGMA threads] command) and the amount of content
2112
** to be sorted exceeds the page size times the minimum of the
2113
** [PRAGMA cache_size] setting and this value.
2114
**
2115
** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
2116
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
2117
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
2118
** becomes the [statement journal] spill-to-disk threshold.
2119
** [Statement journals] are held in memory until their size (in bytes)
2120
** exceeds this threshold, at which point they are written to disk.
2121
** Or if the threshold is -1, statement journals are always held
2122
** exclusively in memory.
2123
** Since many statement journals never become large, setting the spill
2124
** threshold to a value such as 64KiB can greatly reduce the amount of
2125
** I/O required to support statement rollback.
2126
** The default value for this setting is controlled by the
2127
** [SQLITE_STMTJRNL_SPILL] compile-time option.
2128
**
2129
** [[SQLITE_CONFIG_SORTERREF_SIZE]]
2130
** <dt>SQLITE_CONFIG_SORTERREF_SIZE
2131
** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
2132
** of type (int) - the new value of the sorter-reference size threshold.
2133
** Usually, when SQLite uses an external sort to order records according
2134
** to an ORDER BY clause, all fields required by the caller are present in the
2135
** sorted records. However, if SQLite determines based on the declared type
2136
** of a table column that its values are likely to be very large - larger
2137
** than the configured sorter-reference size threshold - then a reference
2138
** is stored in each sorted record and the required column values loaded
2139
** from the database as records are returned in sorted order. The default
2140
** value for this option is to never use this optimization. Specifying a
2141
** negative value for this option restores the default behavior.
2142
** This option is only available if SQLite is compiled with the
2143
** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
2144
**
2145
** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
2146
** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
2147
** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
2148
** [sqlite3_int64] parameter which is the default maximum size for an in-memory
2149
** database created using [sqlite3_deserialize()].  This default maximum
2150
** size can be adjusted up or down for individual databases using the
2151
** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control].  If this
2152
** configuration setting is never used, then the default maximum is determined
2153
** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option.  If that
2154
** compile-time option is not set, then the default maximum is 1073741824.
2155
**
2156
** [[SQLITE_CONFIG_ROWID_IN_VIEW]]
2157
** <dt>SQLITE_CONFIG_ROWID_IN_VIEW
2158
** <dd>The SQLITE_CONFIG_ROWID_IN_VIEW option enables or disables the ability
2159
** for VIEWs to have a ROWID.  The capability can only be enabled if SQLite is
2160
** compiled with -DSQLITE_ALLOW_ROWID_IN_VIEW, in which case the capability
2161
** defaults to on.  This configuration option queries the current setting or
2162
** changes the setting to off or on.  The argument is a pointer to an integer.
2163
** If that integer initially holds a value of 1, then the ability for VIEWs to
2164
** have ROWIDs is activated.  If the integer initially holds zero, then the
2165
** ability is deactivated.  Any other initial value for the integer leaves the
2166
** setting unchanged.  After changes, if any, the integer is written with
2167
** a 1 or 0, if the ability for VIEWs to have ROWIDs is on or off.  If SQLite
2168
** is compiled without -DSQLITE_ALLOW_ROWID_IN_VIEW (which is the usual and
2169
** recommended case) then the integer is always filled with zero, regardless
2170
** if its initial value.
2171
** </dl>
2172
*/
2173
#define SQLITE_CONFIG_SINGLETHREAD         1  /* nil */
2174
#define SQLITE_CONFIG_MULTITHREAD          2  /* nil */
2175
#define SQLITE_CONFIG_SERIALIZED           3  /* nil */
2176
#define SQLITE_CONFIG_MALLOC               4  /* sqlite3_mem_methods* */
2177
#define SQLITE_CONFIG_GETMALLOC            5  /* sqlite3_mem_methods* */
2178
#define SQLITE_CONFIG_SCRATCH              6  /* No longer used */
2179
#define SQLITE_CONFIG_PAGECACHE            7  /* void*, int sz, int N */
2180
#define SQLITE_CONFIG_HEAP                 8  /* void*, int nByte, int min */
2181
#define SQLITE_CONFIG_MEMSTATUS            9  /* boolean */
2182
#define SQLITE_CONFIG_MUTEX               10  /* sqlite3_mutex_methods* */
2183
#define SQLITE_CONFIG_GETMUTEX            11  /* sqlite3_mutex_methods* */
2184
/* previously SQLITE_CONFIG_CHUNKALLOC    12 which is now unused. */
2185
#define SQLITE_CONFIG_LOOKASIDE           13  /* int int */
2186
#define SQLITE_CONFIG_PCACHE              14  /* no-op */
2187
#define SQLITE_CONFIG_GETPCACHE           15  /* no-op */
2188
#define SQLITE_CONFIG_LOG                 16  /* xFunc, void* */
2189
#define SQLITE_CONFIG_URI                 17  /* int */
2190
#define SQLITE_CONFIG_PCACHE2             18  /* sqlite3_pcache_methods2* */
2191
#define SQLITE_CONFIG_GETPCACHE2          19  /* sqlite3_pcache_methods2* */
2192
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
2193
#define SQLITE_CONFIG_SQLLOG              21  /* xSqllog, void* */
2194
#define SQLITE_CONFIG_MMAP_SIZE           22  /* sqlite3_int64, sqlite3_int64 */
2195
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
2196
#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
2197
#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
2198
#define SQLITE_CONFIG_STMTJRNL_SPILL      26  /* int nByte */
2199
#define SQLITE_CONFIG_SMALL_MALLOC        27  /* boolean */
2200
#define SQLITE_CONFIG_SORTERREF_SIZE      28  /* int nByte */
2201
#define SQLITE_CONFIG_MEMDB_MAXSIZE       29  /* sqlite3_int64 */
2202
#define SQLITE_CONFIG_ROWID_IN_VIEW       30  /* int* */
2203
2204
/*
2205
** CAPI3REF: Database Connection Configuration Options
2206
**
2207
** These constants are the available integer configuration options that
2208
** can be passed as the second argument to the [sqlite3_db_config()] interface.
2209
**
2210
** New configuration options may be added in future releases of SQLite.
2211
** Existing configuration options might be discontinued.  Applications
2212
** should check the return code from [sqlite3_db_config()] to make sure that
2213
** the call worked.  ^The [sqlite3_db_config()] interface will return a
2214
** non-zero [error code] if a discontinued or unsupported configuration option
2215
** is invoked.
2216
**
2217
** <dl>
2218
** [[SQLITE_DBCONFIG_LOOKASIDE]]
2219
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
2220
** <dd> ^This option takes three additional arguments that determine the
2221
** [lookaside memory allocator] configuration for the [database connection].
2222
** ^The first argument (the third parameter to [sqlite3_db_config()] is a
2223
** pointer to a memory buffer to use for lookaside memory.
2224
** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
2225
** may be NULL in which case SQLite will allocate the
2226
** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
2227
** size of each lookaside buffer slot.  ^The third argument is the number of
2228
** slots.  The size of the buffer in the first argument must be greater than
2229
** or equal to the product of the second and third arguments.  The buffer
2230
** must be aligned to an 8-byte boundary.  ^If the second argument to
2231
** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
2232
** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
2233
** configuration for a database connection can only be changed when that
2234
** connection is not currently using lookaside memory, or in other words
2235
** when the "current value" returned by
2236
** [sqlite3_db_status](D,[SQLITE_DBSTATUS_LOOKASIDE_USED],...) is zero.
2237
** Any attempt to change the lookaside memory configuration when lookaside
2238
** memory is in use leaves the configuration unchanged and returns
2239
** [SQLITE_BUSY].)^</dd>
2240
**
2241
** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
2242
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2243
** <dd> ^This option is used to enable or disable the enforcement of
2244
** [foreign key constraints].  There should be two additional arguments.
2245
** The first argument is an integer which is 0 to disable FK enforcement,
2246
** positive to enable FK enforcement or negative to leave FK enforcement
2247
** unchanged.  The second parameter is a pointer to an integer into which
2248
** is written 0 or 1 to indicate whether FK enforcement is off or on
2249
** following this call.  The second parameter may be a NULL pointer, in
2250
** which case the FK enforcement setting is not reported back. </dd>
2251
**
2252
** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]]
2253
** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2254
** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2255
** There should be two additional arguments.
2256
** The first argument is an integer which is 0 to disable triggers,
2257
** positive to enable triggers or negative to leave the setting unchanged.
2258
** The second parameter is a pointer to an integer into which
2259
** is written 0 or 1 to indicate whether triggers are disabled or enabled
2260
** following this call.  The second parameter may be a NULL pointer, in
2261
** which case the trigger setting is not reported back.
2262
**
2263
** <p>Originally this option disabled all triggers.  ^(However, since
2264
** SQLite version 3.35.0, TEMP triggers are still allowed even if
2265
** this option is off.  So, in other words, this option now only disables
2266
** triggers in the main database schema or in the schemas of ATTACH-ed
2267
** databases.)^ </dd>
2268
**
2269
** [[SQLITE_DBCONFIG_ENABLE_VIEW]]
2270
** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt>
2271
** <dd> ^This option is used to enable or disable [CREATE VIEW | views].
2272
** There should be two additional arguments.
2273
** The first argument is an integer which is 0 to disable views,
2274
** positive to enable views or negative to leave the setting unchanged.
2275
** The second parameter is a pointer to an integer into which
2276
** is written 0 or 1 to indicate whether views are disabled or enabled
2277
** following this call.  The second parameter may be a NULL pointer, in
2278
** which case the view setting is not reported back.
2279
**
2280
** <p>Originally this option disabled all views.  ^(However, since
2281
** SQLite version 3.35.0, TEMP views are still allowed even if
2282
** this option is off.  So, in other words, this option now only disables
2283
** views in the main database schema or in the schemas of ATTACH-ed
2284
** databases.)^ </dd>
2285
**
2286
** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
2287
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
2288
** <dd> ^This option is used to enable or disable the
2289
** [fts3_tokenizer()] function which is part of the
2290
** [FTS3] full-text search engine extension.
2291
** There should be two additional arguments.
2292
** The first argument is an integer which is 0 to disable fts3_tokenizer() or
2293
** positive to enable fts3_tokenizer() or negative to leave the setting
2294
** unchanged.
2295
** The second parameter is a pointer to an integer into which
2296
** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
2297
** following this call.  The second parameter may be a NULL pointer, in
2298
** which case the new setting is not reported back. </dd>
2299
**
2300
** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]]
2301
** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2302
** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2303
** interface independently of the [load_extension()] SQL function.
2304
** The [sqlite3_enable_load_extension()] API enables or disables both the
2305
** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2306
** There should be two additional arguments.
2307
** When the first argument to this interface is 1, then only the C-API is
2308
** enabled and the SQL function remains disabled.  If the first argument to
2309
** this interface is 0, then both the C-API and the SQL function are disabled.
2310
** If the first argument is -1, then no changes are made to state of either the
2311
** C-API or the SQL function.
2312
** The second parameter is a pointer to an integer into which
2313
** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2314
** is disabled or enabled following this call.  The second parameter may
2315
** be a NULL pointer, in which case the new setting is not reported back.
2316
** </dd>
2317
**
2318
** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
2319
** <dd> ^This option is used to change the name of the "main" database
2320
** schema.  ^The sole argument is a pointer to a constant UTF8 string
2321
** which will become the new schema name in place of "main".  ^SQLite
2322
** does not make a copy of the new main schema name string, so the application
2323
** must ensure that the argument passed into this DBCONFIG option is unchanged
2324
** until after the database connection closes.
2325
** </dd>
2326
**
2327
** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
2328
** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
2329
** <dd> Usually, when a database in wal mode is closed or detached from a
2330
** database handle, SQLite checks if this will mean that there are now no
2331
** connections at all to the database. If so, it performs a checkpoint
2332
** operation before closing the connection. This option may be used to
2333
** override this behavior. The first parameter passed to this operation
2334
** is an integer - positive to disable checkpoints-on-close, or zero (the
2335
** default) to enable them, and negative to leave the setting unchanged.
2336
** The second parameter is a pointer to an integer
2337
** into which is written 0 or 1 to indicate whether checkpoints-on-close
2338
** have been disabled - 0 if they are not disabled, 1 if they are.
2339
** </dd>
2340
**
2341
** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2342
** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2343
** the [query planner stability guarantee] (QPSG).  When the QPSG is active,
2344
** a single SQL query statement will always use the same algorithm regardless
2345
** of values of [bound parameters].)^ The QPSG disables some query optimizations
2346
** that look at the values of bound parameters, which can make some queries
2347
** slower.  But the QPSG has the advantage of more predictable behavior.  With
2348
** the QPSG active, SQLite will always use the same query plan in the field as
2349
** was used during testing in the lab.
2350
** The first argument to this setting is an integer which is 0 to disable
2351
** the QPSG, positive to enable QPSG, or negative to leave the setting
2352
** unchanged. The second parameter is a pointer to an integer into which
2353
** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
2354
** following this call.
2355
** </dd>
2356
**
2357
** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
2358
** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not
2359
** include output for any operations performed by trigger programs. This
2360
** option is used to set or clear (the default) a flag that governs this
2361
** behavior. The first parameter passed to this operation is an integer -
2362
** positive to enable output for trigger programs, or zero to disable it,
2363
** or negative to leave the setting unchanged.
2364
** The second parameter is a pointer to an integer into which is written
2365
** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
2366
** it is not disabled, 1 if it is.
2367
** </dd>
2368
**
2369
** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt>
2370
** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
2371
** [VACUUM] in order to reset a database back to an empty database
2372
** with no schema and no content. The following process works even for
2373
** a badly corrupted database file:
2374
** <ol>
2375
** <li> If the database connection is newly opened, make sure it has read the
2376
**      database schema by preparing then discarding some query against the
2377
**      database, or calling sqlite3_table_column_metadata(), ignoring any
2378
**      errors.  This step is only necessary if the application desires to keep
2379
**      the database in WAL mode after the reset if it was in WAL mode before
2380
**      the reset.
2381
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
2382
** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
2383
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
2384
** </ol>
2385
** Because resetting a database is destructive and irreversible, the
2386
** process requires the use of this obscure API and multiple steps to
2387
** help ensure that it does not happen by accident. Because this
2388
** feature must be capable of resetting corrupt databases, and
2389
** shutting down virtual tables may require access to that corrupt
2390
** storage, the library must abandon any installed virtual tables
2391
** without calling their xDestroy() methods.
2392
**
2393
** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
2394
** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
2395
** "defensive" flag for a database connection.  When the defensive
2396
** flag is enabled, language features that allow ordinary SQL to
2397
** deliberately corrupt the database file are disabled.  The disabled
2398
** features include but are not limited to the following:
2399
** <ul>
2400
** <li> The [PRAGMA writable_schema=ON] statement.
2401
** <li> The [PRAGMA journal_mode=OFF] statement.
2402
** <li> The [PRAGMA schema_version=N] statement.
2403
** <li> Writes to the [sqlite_dbpage] virtual table.
2404
** <li> Direct writes to [shadow tables].
2405
** </ul>
2406
** </dd>
2407
**
2408
** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
2409
** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
2410
** "writable_schema" flag. This has the same effect and is logically equivalent
2411
** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
2412
** The first argument to this setting is an integer which is 0 to disable
2413
** the writable_schema, positive to enable writable_schema, or negative to
2414
** leave the setting unchanged. The second parameter is a pointer to an
2415
** integer into which is written 0 or 1 to indicate whether the writable_schema
2416
** is enabled or disabled following this call.
2417
** </dd>
2418
**
2419
** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]]
2420
** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt>
2421
** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates
2422
** the legacy behavior of the [ALTER TABLE RENAME] command such it
2423
** behaves as it did prior to [version 3.24.0] (2018-06-04).  See the
2424
** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for
2425
** additional information. This feature can also be turned on and off
2426
** using the [PRAGMA legacy_alter_table] statement.
2427
** </dd>
2428
**
2429
** [[SQLITE_DBCONFIG_DQS_DML]]
2430
** <dt>SQLITE_DBCONFIG_DQS_DML</dt>
2431
** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
2432
** the legacy [double-quoted string literal] misfeature for DML statements
2433
** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
2434
** default value of this setting is determined by the [-DSQLITE_DQS]
2435
** compile-time option.
2436
** </dd>
2437
**
2438
** [[SQLITE_DBCONFIG_DQS_DDL]]
2439
** <dt>SQLITE_DBCONFIG_DQS_DDL</dt>
2440
** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
2441
** the legacy [double-quoted string literal] misfeature for DDL statements,
2442
** such as CREATE TABLE and CREATE INDEX. The
2443
** default value of this setting is determined by the [-DSQLITE_DQS]
2444
** compile-time option.
2445
** </dd>
2446
**
2447
** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
2448
** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</dt>
2449
** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
2450
** assume that database schemas are untainted by malicious content.
2451
** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
2452
** takes additional defensive steps to protect the application from harm
2453
** including:
2454
** <ul>
2455
** <li> Prohibit the use of SQL functions inside triggers, views,
2456
** CHECK constraints, DEFAULT clauses, expression indexes,
2457
** partial indexes, or generated columns
2458
** unless those functions are tagged with [SQLITE_INNOCUOUS].
2459
** <li> Prohibit the use of virtual tables inside of triggers or views
2460
** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS].
2461
** </ul>
2462
** This setting defaults to "on" for legacy compatibility, however
2463
** all applications are advised to turn it off if possible. This setting
2464
** can also be controlled using the [PRAGMA trusted_schema] statement.
2465
** </dd>
2466
**
2467
** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
2468
** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</dt>
2469
** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
2470
** the legacy file format flag.  When activated, this flag causes all newly
2471
** created database file to have a schema format version number (the 4-byte
2472
** integer found at offset 44 into the database header) of 1.  This in turn
2473
** means that the resulting database file will be readable and writable by
2474
** any SQLite version back to 3.0.0 ([dateof:3.0.0]).  Without this setting,
2475
** newly created databases are generally not understandable by SQLite versions
2476
** prior to 3.3.0 ([dateof:3.3.0]).  As these words are written, there
2477
** is now scarcely any need to generate database files that are compatible
2478
** all the way back to version 3.0.0, and so this setting is of little
2479
** practical use, but is provided so that SQLite can continue to claim the
2480
** ability to generate new database files that are compatible with  version
2481
** 3.0.0.
2482
** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on,
2483
** the [VACUUM] command will fail with an obscure error when attempting to
2484
** process a table with generated columns and a descending index.  This is
2485
** not considered a bug since SQLite versions 3.3.0 and earlier do not support
2486
** either generated columns or descending indexes.
2487
** </dd>
2488
**
2489
** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]]
2490
** <dt>SQLITE_DBCONFIG_STMT_SCANSTATUS</dt>
2491
** <dd>The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in
2492
** SQLITE_ENABLE_STMT_SCANSTATUS builds. In this case, it sets or clears
2493
** a flag that enables collection of the sqlite3_stmt_scanstatus_v2()
2494
** statistics. For statistics to be collected, the flag must be set on
2495
** the database handle both when the SQL statement is prepared and when it
2496
** is stepped. The flag is set (collection of statistics is enabled)
2497
** by default.  This option takes two arguments: an integer and a pointer to
2498
** an integer..  The first argument is 1, 0, or -1 to enable, disable, or
2499
** leave unchanged the statement scanstatus option.  If the second argument
2500
** is not NULL, then the value of the statement scanstatus setting after
2501
** processing the first argument is written into the integer that the second
2502
** argument points to.
2503
** </dd>
2504
**
2505
** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]]
2506
** <dt>SQLITE_DBCONFIG_REVERSE_SCANORDER</dt>
2507
** <dd>The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order
2508
** in which tables and indexes are scanned so that the scans start at the end
2509
** and work toward the beginning rather than starting at the beginning and
2510
** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the
2511
** same as setting [PRAGMA reverse_unordered_selects].  This option takes
2512
** two arguments which are an integer and a pointer to an integer.  The first
2513
** argument is 1, 0, or -1 to enable, disable, or leave unchanged the
2514
** reverse scan order flag, respectively.  If the second argument is not NULL,
2515
** then 0 or 1 is written into the integer that the second argument points to
2516
** depending on if the reverse scan order flag is set after processing the
2517
** first argument.
2518
** </dd>
2519
**
2520
** </dl>
2521
*/
2522
#define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
2523
#define SQLITE_DBCONFIG_LOOKASIDE             1001 /* void* int int */
2524
#define SQLITE_DBCONFIG_ENABLE_FKEY           1002 /* int int* */
2525
#define SQLITE_DBCONFIG_ENABLE_TRIGGER        1003 /* int int* */
2526
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2527
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
2528
#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE      1006 /* int int* */
2529
#define SQLITE_DBCONFIG_ENABLE_QPSG           1007 /* int int* */
2530
#define SQLITE_DBCONFIG_TRIGGER_EQP           1008 /* int int* */
2531
#define SQLITE_DBCONFIG_RESET_DATABASE        1009 /* int int* */
2532
#define SQLITE_DBCONFIG_DEFENSIVE             1010 /* int int* */
2533
#define SQLITE_DBCONFIG_WRITABLE_SCHEMA       1011 /* int int* */
2534
#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE    1012 /* int int* */
2535
#define SQLITE_DBCONFIG_DQS_DML               1013 /* int int* */
2536
#define SQLITE_DBCONFIG_DQS_DDL               1014 /* int int* */
2537
#define SQLITE_DBCONFIG_ENABLE_VIEW           1015 /* int int* */
2538
#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT    1016 /* int int* */
2539
#define SQLITE_DBCONFIG_TRUSTED_SCHEMA        1017 /* int int* */
2540
#define SQLITE_DBCONFIG_STMT_SCANSTATUS       1018 /* int int* */
2541
#define SQLITE_DBCONFIG_REVERSE_SCANORDER     1019 /* int int* */
2542
#define SQLITE_DBCONFIG_MAX                   1019 /* Largest DBCONFIG */
2543
2544
/*
2545
** CAPI3REF: Enable Or Disable Extended Result Codes
2546
** METHOD: sqlite3
2547
**
2548
** ^The sqlite3_extended_result_codes() routine enables or disables the
2549
** [extended result codes] feature of SQLite. ^The extended result
2550
** codes are disabled by default for historical compatibility.
2551
*/
2552
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2553
2554
/*
2555
** CAPI3REF: Last Insert Rowid
2556
** METHOD: sqlite3
2557
**
2558
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2559
** has a unique 64-bit signed
2560
** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2561
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2562
** names are not also used by explicitly declared columns. ^If
2563
** the table has a column of type [INTEGER PRIMARY KEY] then that column
2564
** is another alias for the rowid.
2565
**
2566
** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2567
** the most recent successful [INSERT] into a rowid table or [virtual table]
2568
** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
2569
** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
2570
** on the database connection D, then sqlite3_last_insert_rowid(D) returns
2571
** zero.
2572
**
2573
** As well as being set automatically as rows are inserted into database
2574
** tables, the value returned by this function may be set explicitly by
2575
** [sqlite3_set_last_insert_rowid()]
2576
**
2577
** Some virtual table implementations may INSERT rows into rowid tables as
2578
** part of committing a transaction (e.g. to flush data accumulated in memory
2579
** to disk). In this case subsequent calls to this function return the rowid
2580
** associated with these internal INSERT operations, which leads to
2581
** unintuitive results. Virtual table implementations that do write to rowid
2582
** tables in this way can avoid this problem by restoring the original
2583
** rowid value using [sqlite3_set_last_insert_rowid()] before returning
2584
** control to the user.
2585
**
2586
** ^(If an [INSERT] occurs within a trigger then this routine will
2587
** return the [rowid] of the inserted row as long as the trigger is
2588
** running. Once the trigger program ends, the value returned
2589
** by this routine reverts to what it was before the trigger was fired.)^
2590
**
2591
** ^An [INSERT] that fails due to a constraint violation is not a
2592
** successful [INSERT] and does not change the value returned by this
2593
** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2594
** and INSERT OR ABORT make no changes to the return value of this
2595
** routine when their insertion fails.  ^(When INSERT OR REPLACE
2596
** encounters a constraint violation, it does not fail.  The
2597
** INSERT continues to completion after deleting rows that caused
2598
** the constraint problem so INSERT OR REPLACE will always change
2599
** the return value of this interface.)^
2600
**
2601
** ^For the purposes of this routine, an [INSERT] is considered to
2602
** be successful even if it is subsequently rolled back.
2603
**
2604
** This function is accessible to SQL statements via the
2605
** [last_insert_rowid() SQL function].
2606
**
2607
** If a separate thread performs a new [INSERT] on the same
2608
** database connection while the [sqlite3_last_insert_rowid()]
2609
** function is running and thus changes the last insert [rowid],
2610
** then the value returned by [sqlite3_last_insert_rowid()] is
2611
** unpredictable and might not equal either the old or the new
2612
** last insert [rowid].
2613
*/
2614
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2615
2616
/*
2617
** CAPI3REF: Set the Last Insert Rowid value.
2618
** METHOD: sqlite3
2619
**
2620
** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
2621
** set the value returned by calling sqlite3_last_insert_rowid(D) to R
2622
** without inserting a row into the database.
2623
*/
2624
SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
2625
2626
/*
2627
** CAPI3REF: Count The Number Of Rows Modified
2628
** METHOD: sqlite3
2629
**
2630
** ^These functions return the number of rows modified, inserted or
2631
** deleted by the most recently completed INSERT, UPDATE or DELETE
2632
** statement on the database connection specified by the only parameter.
2633
** The two functions are identical except for the type of the return value
2634
** and that if the number of rows modified by the most recent INSERT, UPDATE
2635
** or DELETE is greater than the maximum value supported by type "int", then
2636
** the return value of sqlite3_changes() is undefined. ^Executing any other
2637
** type of SQL statement does not modify the value returned by these functions.
2638
**
2639
** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2640
** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2641
** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2642
**
2643
** Changes to a view that are intercepted by
2644
** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2645
** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2646
** DELETE statement run on a view is always zero. Only changes made to real
2647
** tables are counted.
2648
**
2649
** Things are more complicated if the sqlite3_changes() function is
2650
** executed while a trigger program is running. This may happen if the
2651
** program uses the [changes() SQL function], or if some other callback
2652
** function invokes sqlite3_changes() directly. Essentially:
2653
**
2654
** <ul>
2655
**   <li> ^(Before entering a trigger program the value returned by
2656
**        sqlite3_changes() function is saved. After the trigger program
2657
**        has finished, the original value is restored.)^
2658
**
2659
**   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2660
**        statement sets the value returned by sqlite3_changes()
2661
**        upon completion as normal. Of course, this value will not include
2662
**        any changes performed by sub-triggers, as the sqlite3_changes()
2663
**        value will be saved and restored after each sub-trigger has run.)^
2664
** </ul>
2665
**
2666
** ^This means that if the changes() SQL function (or similar) is used
2667
** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2668
** returns the value as set when the calling statement began executing.
2669
** ^If it is used by the second or subsequent such statement within a trigger
2670
** program, the value returned reflects the number of rows modified by the
2671
** previous INSERT, UPDATE or DELETE statement within the same trigger.
2672
**
2673
** If a separate thread makes changes on the same database connection
2674
** while [sqlite3_changes()] is running then the value returned
2675
** is unpredictable and not meaningful.
2676
**
2677
** See also:
2678
** <ul>
2679
** <li> the [sqlite3_total_changes()] interface
2680
** <li> the [count_changes pragma]
2681
** <li> the [changes() SQL function]
2682
** <li> the [data_version pragma]
2683
** </ul>
2684
*/
2685
SQLITE_API int sqlite3_changes(sqlite3*);
2686
SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*);
2687
2688
/*
2689
** CAPI3REF: Total Number Of Rows Modified
2690
** METHOD: sqlite3
2691
**
2692
** ^These functions return the total number of rows inserted, modified or
2693
** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2694
** since the database connection was opened, including those executed as
2695
** part of trigger programs. The two functions are identical except for the
2696
** type of the return value and that if the number of rows modified by the
2697
** connection exceeds the maximum value supported by type "int", then
2698
** the return value of sqlite3_total_changes() is undefined. ^Executing
2699
** any other type of SQL statement does not affect the value returned by
2700
** sqlite3_total_changes().
2701
**
2702
** ^Changes made as part of [foreign key actions] are included in the
2703
** count, but those made as part of REPLACE constraint resolution are
2704
** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2705
** are not counted.
2706
**
2707
** The [sqlite3_total_changes(D)] interface only reports the number
2708
** of rows that changed due to SQL statement run against database
2709
** connection D.  Any changes by other database connections are ignored.
2710
** To detect changes against a database file from other database
2711
** connections use the [PRAGMA data_version] command or the
2712
** [SQLITE_FCNTL_DATA_VERSION] [file control].
2713
**
2714
** If a separate thread makes changes on the same database connection
2715
** while [sqlite3_total_changes()] is running then the value
2716
** returned is unpredictable and not meaningful.
2717
**
2718
** See also:
2719
** <ul>
2720
** <li> the [sqlite3_changes()] interface
2721
** <li> the [count_changes pragma]
2722
** <li> the [changes() SQL function]
2723
** <li> the [data_version pragma]
2724
** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control]
2725
** </ul>
2726
*/
2727
SQLITE_API int sqlite3_total_changes(sqlite3*);
2728
SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*);
2729
2730
/*
2731
** CAPI3REF: Interrupt A Long-Running Query
2732
** METHOD: sqlite3
2733
**
2734
** ^This function causes any pending database operation to abort and
2735
** return at its earliest opportunity. This routine is typically
2736
** called in response to a user action such as pressing "Cancel"
2737
** or Ctrl-C where the user wants a long query operation to halt
2738
** immediately.
2739
**
2740
** ^It is safe to call this routine from a thread different from the
2741
** thread that is currently running the database operation.  But it
2742
** is not safe to call this routine with a [database connection] that
2743
** is closed or might close before sqlite3_interrupt() returns.
2744
**
2745
** ^If an SQL operation is very nearly finished at the time when
2746
** sqlite3_interrupt() is called, then it might not have an opportunity
2747
** to be interrupted and might continue to completion.
2748
**
2749
** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2750
** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2751
** that is inside an explicit transaction, then the entire transaction
2752
** will be rolled back automatically.
2753
**
2754
** ^The sqlite3_interrupt(D) call is in effect until all currently running
2755
** SQL statements on [database connection] D complete.  ^Any new SQL statements
2756
** that are started after the sqlite3_interrupt() call and before the
2757
** running statement count reaches zero are interrupted as if they had been
2758
** running prior to the sqlite3_interrupt() call.  ^New SQL statements
2759
** that are started after the running statement count reaches zero are
2760
** not effected by the sqlite3_interrupt().
2761
** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2762
** SQL statements is a no-op and has no effect on SQL statements
2763
** that are started after the sqlite3_interrupt() call returns.
2764
**
2765
** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether
2766
** or not an interrupt is currently in effect for [database connection] D.
2767
** It returns 1 if an interrupt is currently in effect, or 0 otherwise.
2768
*/
2769
SQLITE_API void sqlite3_interrupt(sqlite3*);
2770
SQLITE_API int sqlite3_is_interrupted(sqlite3*);
2771
2772
/*
2773
** CAPI3REF: Determine If An SQL Statement Is Complete
2774
**
2775
** These routines are useful during command-line input to determine if the
2776
** currently entered text seems to form a complete SQL statement or
2777
** if additional input is needed before sending the text into
2778
** SQLite for parsing.  ^These routines return 1 if the input string
2779
** appears to be a complete SQL statement.  ^A statement is judged to be
2780
** complete if it ends with a semicolon token and is not a prefix of a
2781
** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
2782
** string literals or quoted identifier names or comments are not
2783
** independent tokens (they are part of the token in which they are
2784
** embedded) and thus do not count as a statement terminator.  ^Whitespace
2785
** and comments that follow the final semicolon are ignored.
2786
**
2787
** ^These routines return 0 if the statement is incomplete.  ^If a
2788
** memory allocation fails, then SQLITE_NOMEM is returned.
2789
**
2790
** ^These routines do not parse the SQL statements thus
2791
** will not detect syntactically incorrect SQL.
2792
**
2793
** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2794
** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2795
** automatically by sqlite3_complete16().  If that initialization fails,
2796
** then the return value from sqlite3_complete16() will be non-zero
2797
** regardless of whether or not the input SQL is complete.)^
2798
**
2799
** The input to [sqlite3_complete()] must be a zero-terminated
2800
** UTF-8 string.
2801
**
2802
** The input to [sqlite3_complete16()] must be a zero-terminated
2803
** UTF-16 string in native byte order.
2804
*/
2805
SQLITE_API int sqlite3_complete(const char *sql);
2806
SQLITE_API int sqlite3_complete16(const void *sql);
2807
2808
/*
2809
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2810
** KEYWORDS: {busy-handler callback} {busy handler}
2811
** METHOD: sqlite3
2812
**
2813
** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2814
** that might be invoked with argument P whenever
2815
** an attempt is made to access a database table associated with
2816
** [database connection] D when another thread
2817
** or process has the table locked.
2818
** The sqlite3_busy_handler() interface is used to implement
2819
** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
2820
**
2821
** ^If the busy callback is NULL, then [SQLITE_BUSY]
2822
** is returned immediately upon encountering the lock.  ^If the busy callback
2823
** is not NULL, then the callback might be invoked with two arguments.
2824
**
2825
** ^The first argument to the busy handler is a copy of the void* pointer which
2826
** is the third argument to sqlite3_busy_handler().  ^The second argument to
2827
** the busy handler callback is the number of times that the busy handler has
2828
** been invoked previously for the same locking event.  ^If the
2829
** busy callback returns 0, then no additional attempts are made to
2830
** access the database and [SQLITE_BUSY] is returned
2831
** to the application.
2832
** ^If the callback returns non-zero, then another attempt
2833
** is made to access the database and the cycle repeats.
2834
**
2835
** The presence of a busy handler does not guarantee that it will be invoked
2836
** when there is lock contention. ^If SQLite determines that invoking the busy
2837
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
2838
** to the application instead of invoking the
2839
** busy handler.
2840
** Consider a scenario where one process is holding a read lock that
2841
** it is trying to promote to a reserved lock and
2842
** a second process is holding a reserved lock that it is trying
2843
** to promote to an exclusive lock.  The first process cannot proceed
2844
** because it is blocked by the second and the second process cannot
2845
** proceed because it is blocked by the first.  If both processes
2846
** invoke the busy handlers, neither will make any progress.  Therefore,
2847
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2848
** will induce the first process to release its read lock and allow
2849
** the second process to proceed.
2850
**
2851
** ^The default busy callback is NULL.
2852
**
2853
** ^(There can only be a single busy handler defined for each
2854
** [database connection].  Setting a new busy handler clears any
2855
** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
2856
** or evaluating [PRAGMA busy_timeout=N] will change the
2857
** busy handler and thus clear any previously set busy handler.
2858
**
2859
** The busy callback should not take any actions which modify the
2860
** database connection that invoked the busy handler.  In other words,
2861
** the busy handler is not reentrant.  Any such actions
2862
** result in undefined behavior.
2863
**
2864
** A busy handler must not close the database connection
2865
** or [prepared statement] that invoked the busy handler.
2866
*/
2867
SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
2868
2869
/*
2870
** CAPI3REF: Set A Busy Timeout
2871
** METHOD: sqlite3
2872
**
2873
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2874
** for a specified amount of time when a table is locked.  ^The handler
2875
** will sleep multiple times until at least "ms" milliseconds of sleeping
2876
** have accumulated.  ^After at least "ms" milliseconds of sleeping,
2877
** the handler returns 0 which causes [sqlite3_step()] to return
2878
** [SQLITE_BUSY].
2879
**
2880
** ^Calling this routine with an argument less than or equal to zero
2881
** turns off all busy handlers.
2882
**
2883
** ^(There can only be a single busy handler for a particular
2884
** [database connection] at any given moment.  If another busy handler
2885
** was defined  (using [sqlite3_busy_handler()]) prior to calling
2886
** this routine, that other busy handler is cleared.)^
2887
**
2888
** See also:  [PRAGMA busy_timeout]
2889
*/
2890
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
2891
2892
/*
2893
** CAPI3REF: Convenience Routines For Running Queries
2894
** METHOD: sqlite3
2895
**
2896
** This is a legacy interface that is preserved for backwards compatibility.
2897
** Use of this interface is not recommended.
2898
**
2899
** Definition: A <b>result table</b> is memory data structure created by the
2900
** [sqlite3_get_table()] interface.  A result table records the
2901
** complete query results from one or more queries.
2902
**
2903
** The table conceptually has a number of rows and columns.  But
2904
** these numbers are not part of the result table itself.  These
2905
** numbers are obtained separately.  Let N be the number of rows
2906
** and M be the number of columns.
2907
**
2908
** A result table is an array of pointers to zero-terminated UTF-8 strings.
2909
** There are (N+1)*M elements in the array.  The first M pointers point
2910
** to zero-terminated strings that  contain the names of the columns.
2911
** The remaining entries all point to query results.  NULL values result
2912
** in NULL pointers.  All other values are in their UTF-8 zero-terminated
2913
** string representation as returned by [sqlite3_column_text()].
2914
**
2915
** A result table might consist of one or more memory allocations.
2916
** It is not safe to pass a result table directly to [sqlite3_free()].
2917
** A result table should be deallocated using [sqlite3_free_table()].
2918
**
2919
** ^(As an example of the result table format, suppose a query result
2920
** is as follows:
2921
**
2922
** <blockquote><pre>
2923
**        Name        | Age
2924
**        -----------------------
2925
**        Alice       | 43
2926
**        Bob         | 28
2927
**        Cindy       | 21
2928
** </pre></blockquote>
2929
**
2930
** There are two columns (M==2) and three rows (N==3).  Thus the
2931
** result table has 8 entries.  Suppose the result table is stored
2932
** in an array named azResult.  Then azResult holds this content:
2933
**
2934
** <blockquote><pre>
2935
**        azResult&#91;0] = "Name";
2936
**        azResult&#91;1] = "Age";
2937
**        azResult&#91;2] = "Alice";
2938
**        azResult&#91;3] = "43";
2939
**        azResult&#91;4] = "Bob";
2940
**        azResult&#91;5] = "28";
2941
**        azResult&#91;6] = "Cindy";
2942
**        azResult&#91;7] = "21";
2943
** </pre></blockquote>)^
2944
**
2945
** ^The sqlite3_get_table() function evaluates one or more
2946
** semicolon-separated SQL statements in the zero-terminated UTF-8
2947
** string of its 2nd parameter and returns a result table to the
2948
** pointer given in its 3rd parameter.
2949
**
2950
** After the application has finished with the result from sqlite3_get_table(),
2951
** it must pass the result table pointer to sqlite3_free_table() in order to
2952
** release the memory that was malloced.  Because of the way the
2953
** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2954
** function must not try to call [sqlite3_free()] directly.  Only
2955
** [sqlite3_free_table()] is able to release the memory properly and safely.
2956
**
2957
** The sqlite3_get_table() interface is implemented as a wrapper around
2958
** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
2959
** to any internal data structures of SQLite.  It uses only the public
2960
** interface defined here.  As a consequence, errors that occur in the
2961
** wrapper layer outside of the internal [sqlite3_exec()] call are not
2962
** reflected in subsequent calls to [sqlite3_errcode()] or
2963
** [sqlite3_errmsg()].
2964
*/
2965
SQLITE_API int sqlite3_get_table(
2966
  sqlite3 *db,          /* An open database */
2967
  const char *zSql,     /* SQL to be evaluated */
2968
  char ***pazResult,    /* Results of the query */
2969
  int *pnRow,           /* Number of result rows written here */
2970
  int *pnColumn,        /* Number of result columns written here */
2971
  char **pzErrmsg       /* Error msg written here */
2972
);
2973
SQLITE_API void sqlite3_free_table(char **result);
2974
2975
/*
2976
** CAPI3REF: Formatted String Printing Functions
2977
**
2978
** These routines are work-alikes of the "printf()" family of functions
2979
** from the standard C library.
2980
** These routines understand most of the common formatting options from
2981
** the standard library printf()
2982
** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
2983
** See the [built-in printf()] documentation for details.
2984
**
2985
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
2986
** results into memory obtained from [sqlite3_malloc64()].
2987
** The strings returned by these two routines should be
2988
** released by [sqlite3_free()].  ^Both routines return a
2989
** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
2990
** memory to hold the resulting string.
2991
**
2992
** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2993
** the standard C library.  The result is written into the
2994
** buffer supplied as the second parameter whose size is given by
2995
** the first parameter. Note that the order of the
2996
** first two parameters is reversed from snprintf().)^  This is an
2997
** historical accident that cannot be fixed without breaking
2998
** backwards compatibility.  ^(Note also that sqlite3_snprintf()
2999
** returns a pointer to its buffer instead of the number of
3000
** characters actually written into the buffer.)^  We admit that
3001
** the number of characters written would be a more useful return
3002
** value but we cannot change the implementation of sqlite3_snprintf()
3003
** now without breaking compatibility.
3004
**
3005
** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
3006
** guarantees that the buffer is always zero-terminated.  ^The first
3007
** parameter "n" is the total size of the buffer, including space for
3008
** the zero terminator.  So the longest string that can be completely
3009
** written will be n-1 characters.
3010
**
3011
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
3012
**
3013
** See also:  [built-in printf()], [printf() SQL function]
3014
*/
3015
SQLITE_API char *sqlite3_mprintf(const char*,...);
3016
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
3017
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
3018
SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
3019
3020
/*
3021
** CAPI3REF: Memory Allocation Subsystem
3022
**
3023
** The SQLite core uses these three routines for all of its own
3024
** internal memory allocation needs. "Core" in the previous sentence
3025
** does not include operating-system specific [VFS] implementation.  The
3026
** Windows VFS uses native malloc() and free() for some operations.
3027
**
3028
** ^The sqlite3_malloc() routine returns a pointer to a block
3029
** of memory at least N bytes in length, where N is the parameter.
3030
** ^If sqlite3_malloc() is unable to obtain sufficient free
3031
** memory, it returns a NULL pointer.  ^If the parameter N to
3032
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
3033
** a NULL pointer.
3034
**
3035
** ^The sqlite3_malloc64(N) routine works just like
3036
** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
3037
** of a signed 32-bit integer.
3038
**
3039
** ^Calling sqlite3_free() with a pointer previously returned
3040
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
3041
** that it might be reused.  ^The sqlite3_free() routine is
3042
** a no-op if is called with a NULL pointer.  Passing a NULL pointer
3043
** to sqlite3_free() is harmless.  After being freed, memory
3044
** should neither be read nor written.  Even reading previously freed
3045
** memory might result in a segmentation fault or other severe error.
3046
** Memory corruption, a segmentation fault, or other severe error
3047
** might result if sqlite3_free() is called with a non-NULL pointer that
3048
** was not obtained from sqlite3_malloc() or sqlite3_realloc().
3049
**
3050
** ^The sqlite3_realloc(X,N) interface attempts to resize a
3051
** prior memory allocation X to be at least N bytes.
3052
** ^If the X parameter to sqlite3_realloc(X,N)
3053
** is a NULL pointer then its behavior is identical to calling
3054
** sqlite3_malloc(N).
3055
** ^If the N parameter to sqlite3_realloc(X,N) is zero or
3056
** negative then the behavior is exactly the same as calling
3057
** sqlite3_free(X).
3058
** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
3059
** of at least N bytes in size or NULL if insufficient memory is available.
3060
** ^If M is the size of the prior allocation, then min(N,M) bytes
3061
** of the prior allocation are copied into the beginning of buffer returned
3062
** by sqlite3_realloc(X,N) and the prior allocation is freed.
3063
** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
3064
** prior allocation is not freed.
3065
**
3066
** ^The sqlite3_realloc64(X,N) interfaces works the same as
3067
** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
3068
** of a 32-bit signed integer.
3069
**
3070
** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
3071
** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
3072
** sqlite3_msize(X) returns the size of that memory allocation in bytes.
3073
** ^The value returned by sqlite3_msize(X) might be larger than the number
3074
** of bytes requested when X was allocated.  ^If X is a NULL pointer then
3075
** sqlite3_msize(X) returns zero.  If X points to something that is not
3076
** the beginning of memory allocation, or if it points to a formerly
3077
** valid memory allocation that has now been freed, then the behavior
3078
** of sqlite3_msize(X) is undefined and possibly harmful.
3079
**
3080
** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
3081
** sqlite3_malloc64(), and sqlite3_realloc64()
3082
** is always aligned to at least an 8 byte boundary, or to a
3083
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
3084
** option is used.
3085
**
3086
** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
3087
** must be either NULL or else pointers obtained from a prior
3088
** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
3089
** not yet been released.
3090
**
3091
** The application must not read or write any part of
3092
** a block of memory after it has been released using
3093
** [sqlite3_free()] or [sqlite3_realloc()].
3094
*/
3095
SQLITE_API void *sqlite3_malloc(int);
3096
SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
3097
SQLITE_API void *sqlite3_realloc(void*, int);
3098
SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
3099
SQLITE_API void sqlite3_free(void*);
3100
SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
3101
3102
/*
3103
** CAPI3REF: Memory Allocator Statistics
3104
**
3105
** SQLite provides these two interfaces for reporting on the status
3106
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
3107
** routines, which form the built-in memory allocation subsystem.
3108
**
3109
** ^The [sqlite3_memory_used()] routine returns the number of bytes
3110
** of memory currently outstanding (malloced but not freed).
3111
** ^The [sqlite3_memory_highwater()] routine returns the maximum
3112
** value of [sqlite3_memory_used()] since the high-water mark
3113
** was last reset.  ^The values returned by [sqlite3_memory_used()] and
3114
** [sqlite3_memory_highwater()] include any overhead
3115
** added by SQLite in its implementation of [sqlite3_malloc()],
3116
** but not overhead added by the any underlying system library
3117
** routines that [sqlite3_malloc()] may call.
3118
**
3119
** ^The memory high-water mark is reset to the current value of
3120
** [sqlite3_memory_used()] if and only if the parameter to
3121
** [sqlite3_memory_highwater()] is true.  ^The value returned
3122
** by [sqlite3_memory_highwater(1)] is the high-water mark
3123
** prior to the reset.
3124
*/
3125
SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
3126
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
3127
3128
/*
3129
** CAPI3REF: Pseudo-Random Number Generator
3130
**
3131
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
3132
** select random [ROWID | ROWIDs] when inserting new records into a table that
3133
** already uses the largest possible [ROWID].  The PRNG is also used for
3134
** the built-in random() and randomblob() SQL functions.  This interface allows
3135
** applications to access the same PRNG for other purposes.
3136
**
3137
** ^A call to this routine stores N bytes of randomness into buffer P.
3138
** ^The P parameter can be a NULL pointer.
3139
**
3140
** ^If this routine has not been previously called or if the previous
3141
** call had N less than one or a NULL pointer for P, then the PRNG is
3142
** seeded using randomness obtained from the xRandomness method of
3143
** the default [sqlite3_vfs] object.
3144
** ^If the previous call to this routine had an N of 1 or more and a
3145
** non-NULL P then the pseudo-randomness is generated
3146
** internally and without recourse to the [sqlite3_vfs] xRandomness
3147
** method.
3148
*/
3149
SQLITE_API void sqlite3_randomness(int N, void *P);
3150
3151
/*
3152
** CAPI3REF: Compile-Time Authorization Callbacks
3153
** METHOD: sqlite3
3154
** KEYWORDS: {authorizer callback}
3155
**
3156
** ^This routine registers an authorizer callback with a particular
3157
** [database connection], supplied in the first argument.
3158
** ^The authorizer callback is invoked as SQL statements are being compiled
3159
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
3160
** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
3161
** and [sqlite3_prepare16_v3()].  ^At various
3162
** points during the compilation process, as logic is being created
3163
** to perform various actions, the authorizer callback is invoked to
3164
** see if those actions are allowed.  ^The authorizer callback should
3165
** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
3166
** specific action but allow the SQL statement to continue to be
3167
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
3168
** rejected with an error.  ^If the authorizer callback returns
3169
** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
3170
** then the [sqlite3_prepare_v2()] or equivalent call that triggered
3171
** the authorizer will fail with an error message.
3172
**
3173
** When the callback returns [SQLITE_OK], that means the operation
3174
** requested is ok.  ^When the callback returns [SQLITE_DENY], the
3175
** [sqlite3_prepare_v2()] or equivalent call that triggered the
3176
** authorizer will fail with an error message explaining that
3177
** access is denied.
3178
**
3179
** ^The first parameter to the authorizer callback is a copy of the third
3180
** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
3181
** to the callback is an integer [SQLITE_COPY | action code] that specifies
3182
** the particular action to be authorized. ^The third through sixth parameters
3183
** to the callback are either NULL pointers or zero-terminated strings
3184
** that contain additional details about the action to be authorized.
3185
** Applications must always be prepared to encounter a NULL pointer in any
3186
** of the third through the sixth parameters of the authorization callback.
3187
**
3188
** ^If the action code is [SQLITE_READ]
3189
** and the callback returns [SQLITE_IGNORE] then the
3190
** [prepared statement] statement is constructed to substitute
3191
** a NULL value in place of the table column that would have
3192
** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
3193
** return can be used to deny an untrusted user access to individual
3194
** columns of a table.
3195
** ^When a table is referenced by a [SELECT] but no column values are
3196
** extracted from that table (for example in a query like
3197
** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
3198
** is invoked once for that table with a column name that is an empty string.
3199
** ^If the action code is [SQLITE_DELETE] and the callback returns
3200
** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
3201
** [truncate optimization] is disabled and all rows are deleted individually.
3202
**
3203
** An authorizer is used when [sqlite3_prepare | preparing]
3204
** SQL statements from an untrusted source, to ensure that the SQL statements
3205
** do not try to access data they are not allowed to see, or that they do not
3206
** try to execute malicious statements that damage the database.  For
3207
** example, an application may allow a user to enter arbitrary
3208
** SQL queries for evaluation by a database.  But the application does
3209
** not want the user to be able to make arbitrary changes to the
3210
** database.  An authorizer could then be put in place while the
3211
** user-entered SQL is being [sqlite3_prepare | prepared] that
3212
** disallows everything except [SELECT] statements.
3213
**
3214
** Applications that need to process SQL from untrusted sources
3215
** might also consider lowering resource limits using [sqlite3_limit()]
3216
** and limiting database size using the [max_page_count] [PRAGMA]
3217
** in addition to using an authorizer.
3218
**
3219
** ^(Only a single authorizer can be in place on a database connection
3220
** at a time.  Each call to sqlite3_set_authorizer overrides the
3221
** previous call.)^  ^Disable the authorizer by installing a NULL callback.
3222
** The authorizer is disabled by default.
3223
**
3224
** The authorizer callback must not do anything that will modify
3225
** the database connection that invoked the authorizer callback.
3226
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3227
** database connections for the meaning of "modify" in this paragraph.
3228
**
3229
** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
3230
** statement might be re-prepared during [sqlite3_step()] due to a
3231
** schema change.  Hence, the application should ensure that the
3232
** correct authorizer callback remains in place during the [sqlite3_step()].
3233
**
3234
** ^Note that the authorizer callback is invoked only during
3235
** [sqlite3_prepare()] or its variants.  Authorization is not
3236
** performed during statement evaluation in [sqlite3_step()], unless
3237
** as stated in the previous paragraph, sqlite3_step() invokes
3238
** sqlite3_prepare_v2() to reprepare a statement after a schema change.
3239
*/
3240
SQLITE_API int sqlite3_set_authorizer(
3241
  sqlite3*,
3242
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
3243
  void *pUserData
3244
);
3245
3246
/*
3247
** CAPI3REF: Authorizer Return Codes
3248
**
3249
** The [sqlite3_set_authorizer | authorizer callback function] must
3250
** return either [SQLITE_OK] or one of these two constants in order
3251
** to signal SQLite whether or not the action is permitted.  See the
3252
** [sqlite3_set_authorizer | authorizer documentation] for additional
3253
** information.
3254
**
3255
** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
3256
** returned from the [sqlite3_vtab_on_conflict()] interface.
3257
*/
3258
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
3259
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
3260
3261
/*
3262
** CAPI3REF: Authorizer Action Codes
3263
**
3264
** The [sqlite3_set_authorizer()] interface registers a callback function
3265
** that is invoked to authorize certain SQL statement actions.  The
3266
** second parameter to the callback is an integer code that specifies
3267
** what action is being authorized.  These are the integer action codes that
3268
** the authorizer callback may be passed.
3269
**
3270
** These action code values signify what kind of operation is to be
3271
** authorized.  The 3rd and 4th parameters to the authorization
3272
** callback function will be parameters or NULL depending on which of these
3273
** codes is used as the second parameter.  ^(The 5th parameter to the
3274
** authorizer callback is the name of the database ("main", "temp",
3275
** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
3276
** is the name of the inner-most trigger or view that is responsible for
3277
** the access attempt or NULL if this access attempt is directly from
3278
** top-level SQL code.
3279
*/
3280
/******************************************* 3rd ************ 4th ***********/
3281
#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
3282
#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
3283
#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
3284
#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
3285
#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
3286
#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
3287
#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
3288
#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
3289
#define SQLITE_DELETE                9   /* Table Name      NULL            */
3290
#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
3291
#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
3292
#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
3293
#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
3294
#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
3295
#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
3296
#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
3297
#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
3298
#define SQLITE_INSERT               18   /* Table Name      NULL            */
3299
#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
3300
#define SQLITE_READ                 20   /* Table Name      Column Name     */
3301
#define SQLITE_SELECT               21   /* NULL            NULL            */
3302
#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
3303
#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
3304
#define SQLITE_ATTACH               24   /* Filename        NULL            */
3305
#define SQLITE_DETACH               25   /* Database Name   NULL            */
3306
#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
3307
#define SQLITE_REINDEX              27   /* Index Name      NULL            */
3308
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
3309
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
3310
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
3311
#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
3312
#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
3313
#define SQLITE_COPY                  0   /* No longer used */
3314
#define SQLITE_RECURSIVE            33   /* NULL            NULL            */
3315
3316
/*
3317
** CAPI3REF: Deprecated Tracing And Profiling Functions
3318
** DEPRECATED
3319
**
3320
** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
3321
** instead of the routines described here.
3322
**
3323
** These routines register callback functions that can be used for
3324
** tracing and profiling the execution of SQL statements.
3325
**
3326
** ^The callback function registered by sqlite3_trace() is invoked at
3327
** various times when an SQL statement is being run by [sqlite3_step()].
3328
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
3329
** SQL statement text as the statement first begins executing.
3330
** ^(Additional sqlite3_trace() callbacks might occur
3331
** as each triggered subprogram is entered.  The callbacks for triggers
3332
** contain a UTF-8 SQL comment that identifies the trigger.)^
3333
**
3334
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
3335
** the length of [bound parameter] expansion in the output of sqlite3_trace().
3336
**
3337
** ^The callback function registered by sqlite3_profile() is invoked
3338
** as each SQL statement finishes.  ^The profile callback contains
3339
** the original statement text and an estimate of wall-clock time
3340
** of how long that statement took to run.  ^The profile callback
3341
** time is in units of nanoseconds, however the current implementation
3342
** is only capable of millisecond resolution so the six least significant
3343
** digits in the time are meaningless.  Future versions of SQLite
3344
** might provide greater resolution on the profiler callback.  Invoking
3345
** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the
3346
** profile callback.
3347
*/
3348
SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
3349
   void(*xTrace)(void*,const char*), void*);
3350
SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
3351
   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
3352
3353
/*
3354
** CAPI3REF: SQL Trace Event Codes
3355
** KEYWORDS: SQLITE_TRACE
3356
**
3357
** These constants identify classes of events that can be monitored
3358
** using the [sqlite3_trace_v2()] tracing logic.  The M argument
3359
** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
3360
** the following constants.  ^The first argument to the trace callback
3361
** is one of the following constants.
3362
**
3363
** New tracing constants may be added in future releases.
3364
**
3365
** ^A trace callback has four arguments: xCallback(T,C,P,X).
3366
** ^The T argument is one of the integer type codes above.
3367
** ^The C argument is a copy of the context pointer passed in as the
3368
** fourth argument to [sqlite3_trace_v2()].
3369
** The P and X arguments are pointers whose meanings depend on T.
3370
**
3371
** <dl>
3372
** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
3373
** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
3374
** first begins running and possibly at other times during the
3375
** execution of the prepared statement, such as at the start of each
3376
** trigger subprogram. ^The P argument is a pointer to the
3377
** [prepared statement]. ^The X argument is a pointer to a string which
3378
** is the unexpanded SQL text of the prepared statement or an SQL comment
3379
** that indicates the invocation of a trigger.  ^The callback can compute
3380
** the same text that would have been returned by the legacy [sqlite3_trace()]
3381
** interface by using the X argument when X begins with "--" and invoking
3382
** [sqlite3_expanded_sql(P)] otherwise.
3383
**
3384
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
3385
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
3386
** information as is provided by the [sqlite3_profile()] callback.
3387
** ^The P argument is a pointer to the [prepared statement] and the
3388
** X argument points to a 64-bit integer which is approximately
3389
** the number of nanoseconds that the prepared statement took to run.
3390
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
3391
**
3392
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
3393
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
3394
** statement generates a single row of result.
3395
** ^The P argument is a pointer to the [prepared statement] and the
3396
** X argument is unused.
3397
**
3398
** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
3399
** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
3400
** connection closes.
3401
** ^The P argument is a pointer to the [database connection] object
3402
** and the X argument is unused.
3403
** </dl>
3404
*/
3405
#define SQLITE_TRACE_STMT       0x01
3406
#define SQLITE_TRACE_PROFILE    0x02
3407
#define SQLITE_TRACE_ROW        0x04
3408
#define SQLITE_TRACE_CLOSE      0x08
3409
3410
/*
3411
** CAPI3REF: SQL Trace Hook
3412
** METHOD: sqlite3
3413
**
3414
** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
3415
** function X against [database connection] D, using property mask M
3416
** and context pointer P.  ^If the X callback is
3417
** NULL or if the M mask is zero, then tracing is disabled.  The
3418
** M argument should be the bitwise OR-ed combination of
3419
** zero or more [SQLITE_TRACE] constants.
3420
**
3421
** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P)
3422
** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or
3423
** sqlite3_trace_v2(D,M,X,P) for the [database connection] D.  Each
3424
** database connection may have at most one trace callback.
3425
**
3426
** ^The X callback is invoked whenever any of the events identified by
3427
** mask M occur.  ^The integer return value from the callback is currently
3428
** ignored, though this may change in future releases.  Callback
3429
** implementations should return zero to ensure future compatibility.
3430
**
3431
** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
3432
** ^The T argument is one of the [SQLITE_TRACE]
3433
** constants to indicate why the callback was invoked.
3434
** ^The C argument is a copy of the context pointer.
3435
** The P and X arguments are pointers whose meanings depend on T.
3436
**
3437
** The sqlite3_trace_v2() interface is intended to replace the legacy
3438
** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
3439
** are deprecated.
3440
*/
3441
SQLITE_API int sqlite3_trace_v2(
3442
  sqlite3*,
3443
  unsigned uMask,
3444
  int(*xCallback)(unsigned,void*,void*,void*),
3445
  void *pCtx
3446
);
3447
3448
/*
3449
** CAPI3REF: Query Progress Callbacks
3450
** METHOD: sqlite3
3451
**
3452
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
3453
** function X to be invoked periodically during long running calls to
3454
** [sqlite3_step()] and [sqlite3_prepare()] and similar for
3455
** database connection D.  An example use for this
3456
** interface is to keep a GUI updated during a large query.
3457
**
3458
** ^The parameter P is passed through as the only parameter to the
3459
** callback function X.  ^The parameter N is the approximate number of
3460
** [virtual machine instructions] that are evaluated between successive
3461
** invocations of the callback X.  ^If N is less than one then the progress
3462
** handler is disabled.
3463
**
3464
** ^Only a single progress handler may be defined at one time per
3465
** [database connection]; setting a new progress handler cancels the
3466
** old one.  ^Setting parameter X to NULL disables the progress handler.
3467
** ^The progress handler is also disabled by setting N to a value less
3468
** than 1.
3469
**
3470
** ^If the progress callback returns non-zero, the operation is
3471
** interrupted.  This feature can be used to implement a
3472
** "Cancel" button on a GUI progress dialog box.
3473
**
3474
** The progress handler callback must not do anything that will modify
3475
** the database connection that invoked the progress handler.
3476
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3477
** database connections for the meaning of "modify" in this paragraph.
3478
**
3479
** The progress handler callback would originally only be invoked from the
3480
** bytecode engine.  It still might be invoked during [sqlite3_prepare()]
3481
** and similar because those routines might force a reparse of the schema
3482
** which involves running the bytecode engine.  However, beginning with
3483
** SQLite version 3.41.0, the progress handler callback might also be
3484
** invoked directly from [sqlite3_prepare()] while analyzing and generating
3485
** code for complex queries.
3486
*/
3487
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3488
3489
/*
3490
** CAPI3REF: Opening A New Database Connection
3491
** CONSTRUCTOR: sqlite3
3492
**
3493
** ^These routines open an SQLite database file as specified by the
3494
** filename argument. ^The filename argument is interpreted as UTF-8 for
3495
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3496
** order for sqlite3_open16(). ^(A [database connection] handle is usually
3497
** returned in *ppDb, even if an error occurs.  The only exception is that
3498
** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3499
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3500
** object.)^ ^(If the database is opened (and/or created) successfully, then
3501
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
3502
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3503
** an English language description of the error following a failure of any
3504
** of the sqlite3_open() routines.
3505
**
3506
** ^The default encoding will be UTF-8 for databases created using
3507
** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
3508
** created using sqlite3_open16() will be UTF-16 in the native byte order.
3509
**
3510
** Whether or not an error occurs when it is opened, resources
3511
** associated with the [database connection] handle should be released by
3512
** passing it to [sqlite3_close()] when it is no longer required.
3513
**
3514
** The sqlite3_open_v2() interface works like sqlite3_open()
3515
** except that it accepts two additional parameters for additional control
3516
** over the new database connection.  ^(The flags parameter to
3517
** sqlite3_open_v2() must include, at a minimum, one of the following
3518
** three flag combinations:)^
3519
**
3520
** <dl>
3521
** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3522
** <dd>The database is opened in read-only mode.  If the database does
3523
** not already exist, an error is returned.</dd>)^
3524
**
3525
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3526
** <dd>The database is opened for reading and writing if possible, or
3527
** reading only if the file is write protected by the operating
3528
** system.  In either case the database must already exist, otherwise
3529
** an error is returned.  For historical reasons, if opening in
3530
** read-write mode fails due to OS-level permissions, an attempt is
3531
** made to open it in read-only mode. [sqlite3_db_readonly()] can be
3532
** used to determine whether the database is actually
3533
** read-write.</dd>)^
3534
**
3535
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3536
** <dd>The database is opened for reading and writing, and is created if
3537
** it does not already exist. This is the behavior that is always used for
3538
** sqlite3_open() and sqlite3_open16().</dd>)^
3539
** </dl>
3540
**
3541
** In addition to the required flags, the following optional flags are
3542
** also supported:
3543
**
3544
** <dl>
3545
** ^(<dt>[SQLITE_OPEN_URI]</dt>
3546
** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^
3547
**
3548
** ^(<dt>[SQLITE_OPEN_MEMORY]</dt>
3549
** <dd>The database will be opened as an in-memory database.  The database
3550
** is named by the "filename" argument for the purposes of cache-sharing,
3551
** if shared cache mode is enabled, but the "filename" is otherwise ignored.
3552
** </dd>)^
3553
**
3554
** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt>
3555
** <dd>The new database connection will use the "multi-thread"
3556
** [threading mode].)^  This means that separate threads are allowed
3557
** to use SQLite at the same time, as long as each thread is using
3558
** a different [database connection].
3559
**
3560
** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt>
3561
** <dd>The new database connection will use the "serialized"
3562
** [threading mode].)^  This means the multiple threads can safely
3563
** attempt to use the same database connection at the same time.
3564
** (Mutexes will block any actual concurrency, but in this mode
3565
** there is no harm in trying.)
3566
**
3567
** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
3568
** <dd>The database is opened [shared cache] enabled, overriding
3569
** the default shared cache setting provided by
3570
** [sqlite3_enable_shared_cache()].)^
3571
** The [use of shared cache mode is discouraged] and hence shared cache
3572
** capabilities may be omitted from many builds of SQLite.  In such cases,
3573
** this option is a no-op.
3574
**
3575
** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
3576
** <dd>The database is opened [shared cache] disabled, overriding
3577
** the default shared cache setting provided by
3578
** [sqlite3_enable_shared_cache()].)^
3579
**
3580
** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt>
3581
** <dd>The database connection comes up in "extended result code mode".
3582
** In other words, the database behaves as if
3583
** [sqlite3_extended_result_codes(db,1)] were called on the database
3584
** connection as soon as the connection is created. In addition to setting
3585
** the extended result code mode, this flag also causes [sqlite3_open_v2()]
3586
** to return an extended result code.</dd>
3587
**
3588
** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
3589
** <dd>The database filename is not allowed to contain a symbolic link</dd>
3590
** </dl>)^
3591
**
3592
** If the 3rd parameter to sqlite3_open_v2() is not one of the
3593
** required combinations shown above optionally combined with other
3594
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3595
** then the behavior is undefined.  Historic versions of SQLite
3596
** have silently ignored surplus bits in the flags parameter to
3597
** sqlite3_open_v2(), however that behavior might not be carried through
3598
** into future versions of SQLite and so applications should not rely
3599
** upon it.  Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op
3600
** for sqlite3_open_v2().  The SQLITE_OPEN_EXCLUSIVE does *not* cause
3601
** the open to fail if the database already exists.  The SQLITE_OPEN_EXCLUSIVE
3602
** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not
3603
** by sqlite3_open_v2().
3604
**
3605
** ^The fourth parameter to sqlite3_open_v2() is the name of the
3606
** [sqlite3_vfs] object that defines the operating system interface that
3607
** the new database connection should use.  ^If the fourth parameter is
3608
** a NULL pointer then the default [sqlite3_vfs] object is used.
3609
**
3610
** ^If the filename is ":memory:", then a private, temporary in-memory database
3611
** is created for the connection.  ^This in-memory database will vanish when
3612
** the database connection is closed.  Future versions of SQLite might
3613
** make use of additional special filenames that begin with the ":" character.
3614
** It is recommended that when a database filename actually does begin with
3615
** a ":" character you should prefix the filename with a pathname such as
3616
** "./" to avoid ambiguity.
3617
**
3618
** ^If the filename is an empty string, then a private, temporary
3619
** on-disk database will be created.  ^This private database will be
3620
** automatically deleted as soon as the database connection is closed.
3621
**
3622
** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3623
**
3624
** ^If [URI filename] interpretation is enabled, and the filename argument
3625
** begins with "file:", then the filename is interpreted as a URI. ^URI
3626
** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3627
** set in the third argument to sqlite3_open_v2(), or if it has
3628
** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3629
** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3630
** URI filename interpretation is turned off
3631
** by default, but future releases of SQLite might enable URI filename
3632
** interpretation by default.  See "[URI filenames]" for additional
3633
** information.
3634
**
3635
** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3636
** authority, then it must be either an empty string or the string
3637
** "localhost". ^If the authority is not an empty string or "localhost", an
3638
** error is returned to the caller. ^The fragment component of a URI, if
3639
** present, is ignored.
3640
**
3641
** ^SQLite uses the path component of the URI as the name of the disk file
3642
** which contains the database. ^If the path begins with a '/' character,
3643
** then it is interpreted as an absolute path. ^If the path does not begin
3644
** with a '/' (meaning that the authority section is omitted from the URI)
3645
** then the path is interpreted as a relative path.
3646
** ^(On windows, the first component of an absolute path
3647
** is a drive specification (e.g. "C:").)^
3648
**
3649
** [[core URI query parameters]]
3650
** The query component of a URI may contain parameters that are interpreted
3651
** either by SQLite itself, or by a [VFS | custom VFS implementation].
3652
** SQLite and its built-in [VFSes] interpret the
3653
** following query parameters:
3654
**
3655
** <ul>
3656
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3657
**     a VFS object that provides the operating system interface that should
3658
**     be used to access the database file on disk. ^If this option is set to
3659
**     an empty string the default VFS object is used. ^Specifying an unknown
3660
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3661
**     present, then the VFS specified by the option takes precedence over
3662
**     the value passed as the fourth parameter to sqlite3_open_v2().
3663
**
3664
**   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3665
**     "rwc", or "memory". Attempting to set it to any other value is
3666
**     an error)^.
3667
**     ^If "ro" is specified, then the database is opened for read-only
3668
**     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
3669
**     third argument to sqlite3_open_v2(). ^If the mode option is set to
3670
**     "rw", then the database is opened for read-write (but not create)
3671
**     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3672
**     been set. ^Value "rwc" is equivalent to setting both
3673
**     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
3674
**     set to "memory" then a pure [in-memory database] that never reads
3675
**     or writes from disk is used. ^It is an error to specify a value for
3676
**     the mode parameter that is less restrictive than that specified by
3677
**     the flags passed in the third parameter to sqlite3_open_v2().
3678
**
3679
**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3680
**     "private". ^Setting it to "shared" is equivalent to setting the
3681
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3682
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3683
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3684
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3685
**     a URI filename, its value overrides any behavior requested by setting
3686
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3687
**
3688
**  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3689
**     [powersafe overwrite] property does or does not apply to the
3690
**     storage media on which the database file resides.
3691
**
3692
**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3693
**     which if set disables file locking in rollback journal modes.  This
3694
**     is useful for accessing a database on a filesystem that does not
3695
**     support locking.  Caution:  Database corruption might result if two
3696
**     or more processes write to the same database and any one of those
3697
**     processes uses nolock=1.
3698
**
3699
**  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3700
**     parameter that indicates that the database file is stored on
3701
**     read-only media.  ^When immutable is set, SQLite assumes that the
3702
**     database file cannot be changed, even by a process with higher
3703
**     privilege, and so the database is opened read-only and all locking
3704
**     and change detection is disabled.  Caution: Setting the immutable
3705
**     property on a database file that does in fact change can result
3706
**     in incorrect query results and/or [SQLITE_CORRUPT] errors.
3707
**     See also: [SQLITE_IOCAP_IMMUTABLE].
3708
**
3709
** </ul>
3710
**
3711
** ^Specifying an unknown parameter in the query component of a URI is not an
3712
** error.  Future versions of SQLite might understand additional query
3713
** parameters.  See "[query parameters with special meaning to SQLite]" for
3714
** additional information.
3715
**
3716
** [[URI filename examples]] <h3>URI filename examples</h3>
3717
**
3718
** <table border="1" align=center cellpadding=5>
3719
** <tr><th> URI filenames <th> Results
3720
** <tr><td> file:data.db <td>
3721
**          Open the file "data.db" in the current directory.
3722
** <tr><td> file:/home/fred/data.db<br>
3723
**          file:///home/fred/data.db <br>
3724
**          file://localhost/home/fred/data.db <br> <td>
3725
**          Open the database file "/home/fred/data.db".
3726
** <tr><td> file://darkstar/home/fred/data.db <td>
3727
**          An error. "darkstar" is not a recognized authority.
3728
** <tr><td style="white-space:nowrap">
3729
**          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3730
**     <td> Windows only: Open the file "data.db" on fred's desktop on drive
3731
**          C:. Note that the %20 escaping in this example is not strictly
3732
**          necessary - space characters can be used literally
3733
**          in URI filenames.
3734
** <tr><td> file:data.db?mode=ro&cache=private <td>
3735
**          Open file "data.db" in the current directory for read-only access.
3736
**          Regardless of whether or not shared-cache mode is enabled by
3737
**          default, use a private cache.
3738
** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3739
**          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3740
**          that uses dot-files in place of posix advisory locking.
3741
** <tr><td> file:data.db?mode=readonly <td>
3742
**          An error. "readonly" is not a valid option for the "mode" parameter.
3743
**          Use "ro" instead:  "file:data.db?mode=ro".
3744
** </table>
3745
**
3746
** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3747
** query components of a URI. A hexadecimal escape sequence consists of a
3748
** percent sign - "%" - followed by exactly two hexadecimal digits
3749
** specifying an octet value. ^Before the path or query components of a
3750
** URI filename are interpreted, they are encoded using UTF-8 and all
3751
** hexadecimal escape sequences replaced by a single byte containing the
3752
** corresponding octet. If this process generates an invalid UTF-8 encoding,
3753
** the results are undefined.
3754
**
3755
** <b>Note to Windows users:</b>  The encoding used for the filename argument
3756
** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3757
** codepage is currently defined.  Filenames containing international
3758
** characters must be converted to UTF-8 prior to passing them into
3759
** sqlite3_open() or sqlite3_open_v2().
3760
**
3761
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
3762
** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
3763
** features that require the use of temporary files may fail.
3764
**
3765
** See also: [sqlite3_temp_directory]
3766
*/
3767
SQLITE_API int sqlite3_open(
3768
  const char *filename,   /* Database filename (UTF-8) */
3769
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3770
);
3771
SQLITE_API int sqlite3_open16(
3772
  const void *filename,   /* Database filename (UTF-16) */
3773
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3774
);
3775
SQLITE_API int sqlite3_open_v2(
3776
  const char *filename,   /* Database filename (UTF-8) */
3777
  sqlite3 **ppDb,         /* OUT: SQLite db handle */
3778
  int flags,              /* Flags */
3779
  const char *zVfs        /* Name of VFS module to use */
3780
);
3781
3782
/*
3783
** CAPI3REF: Obtain Values For URI Parameters
3784
**
3785
** These are utility routines, useful to [VFS|custom VFS implementations],
3786
** that check if a database file was a URI that contained a specific query
3787
** parameter, and if so obtains the value of that query parameter.
3788
**
3789
** The first parameter to these interfaces (hereafter referred to
3790
** as F) must be one of:
3791
** <ul>
3792
** <li> A database filename pointer created by the SQLite core and
3793
** passed into the xOpen() method of a VFS implementation, or
3794
** <li> A filename obtained from [sqlite3_db_filename()], or
3795
** <li> A new filename constructed using [sqlite3_create_filename()].
3796
** </ul>
3797
** If the F parameter is not one of the above, then the behavior is
3798
** undefined and probably undesirable.  Older versions of SQLite were
3799
** more tolerant of invalid F parameters than newer versions.
3800
**
3801
** If F is a suitable filename (as described in the previous paragraph)
3802
** and if P is the name of the query parameter, then
3803
** sqlite3_uri_parameter(F,P) returns the value of the P
3804
** parameter if it exists or a NULL pointer if P does not appear as a
3805
** query parameter on F.  If P is a query parameter of F and it
3806
** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3807
** a pointer to an empty string.
3808
**
3809
** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3810
** parameter and returns true (1) or false (0) according to the value
3811
** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3812
** value of query parameter P is one of "yes", "true", or "on" in any
3813
** case or if the value begins with a non-zero number.  The
3814
** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3815
** query parameter P is one of "no", "false", or "off" in any case or
3816
** if the value begins with a numeric zero.  If P is not a query
3817
** parameter on F or if the value of P does not match any of the
3818
** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
3819
**
3820
** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3821
** 64-bit signed integer and returns that integer, or D if P does not
3822
** exist.  If the value of P is something other than an integer, then
3823
** zero is returned.
3824
**
3825
** The sqlite3_uri_key(F,N) returns a pointer to the name (not
3826
** the value) of the N-th query parameter for filename F, or a NULL
3827
** pointer if N is less than zero or greater than the number of query
3828
** parameters minus 1.  The N value is zero-based so N should be 0 to obtain
3829
** the name of the first query parameter, 1 for the second parameter, and
3830
** so forth.
3831
**
3832
** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
3833
** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
3834
** is not a database file pathname pointer that the SQLite core passed
3835
** into the xOpen VFS method, then the behavior of this routine is undefined
3836
** and probably undesirable.
3837
**
3838
** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F
3839
** parameter can also be the name of a rollback journal file or WAL file
3840
** in addition to the main database file.  Prior to version 3.31.0, these
3841
** routines would only work if F was the name of the main database file.
3842
** When the F parameter is the name of the rollback journal or WAL file,
3843
** it has access to all the same query parameters as were found on the
3844
** main database file.
3845
**
3846
** See the [URI filename] documentation for additional information.
3847
*/
3848
SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam);
3849
SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault);
3850
SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64);
3851
SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N);
3852
3853
/*
3854
** CAPI3REF:  Translate filenames
3855
**
3856
** These routines are available to [VFS|custom VFS implementations] for
3857
** translating filenames between the main database file, the journal file,
3858
** and the WAL file.
3859
**
3860
** If F is the name of an sqlite database file, journal file, or WAL file
3861
** passed by the SQLite core into the VFS, then sqlite3_filename_database(F)
3862
** returns the name of the corresponding database file.
3863
**
3864
** If F is the name of an sqlite database file, journal file, or WAL file
3865
** passed by the SQLite core into the VFS, or if F is a database filename
3866
** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F)
3867
** returns the name of the corresponding rollback journal file.
3868
**
3869
** If F is the name of an sqlite database file, journal file, or WAL file
3870
** that was passed by the SQLite core into the VFS, or if F is a database
3871
** filename obtained from [sqlite3_db_filename()], then
3872
** sqlite3_filename_wal(F) returns the name of the corresponding
3873
** WAL file.
3874
**
3875
** In all of the above, if F is not the name of a database, journal or WAL
3876
** filename passed into the VFS from the SQLite core and F is not the
3877
** return value from [sqlite3_db_filename()], then the result is
3878
** undefined and is likely a memory access violation.
3879
*/
3880
SQLITE_API const char *sqlite3_filename_database(sqlite3_filename);
3881
SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename);
3882
SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename);
3883
3884
/*
3885
** CAPI3REF:  Database File Corresponding To A Journal
3886
**
3887
** ^If X is the name of a rollback or WAL-mode journal file that is
3888
** passed into the xOpen method of [sqlite3_vfs], then
3889
** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]
3890
** object that represents the main database file.
3891
**
3892
** This routine is intended for use in custom [VFS] implementations
3893
** only.  It is not a general-purpose interface.
3894
** The argument sqlite3_file_object(X) must be a filename pointer that
3895
** has been passed into [sqlite3_vfs].xOpen method where the
3896
** flags parameter to xOpen contains one of the bits
3897
** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL].  Any other use
3898
** of this routine results in undefined and probably undesirable
3899
** behavior.
3900
*/
3901
SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*);
3902
3903
/*
3904
** CAPI3REF: Create and Destroy VFS Filenames
3905
**
3906
** These interfaces are provided for use by [VFS shim] implementations and
3907
** are not useful outside of that context.
3908
**
3909
** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of
3910
** database filename D with corresponding journal file J and WAL file W and
3911
** with N URI parameters key/values pairs in the array P.  The result from
3912
** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that
3913
** is safe to pass to routines like:
3914
** <ul>
3915
** <li> [sqlite3_uri_parameter()],
3916
** <li> [sqlite3_uri_boolean()],
3917
** <li> [sqlite3_uri_int64()],
3918
** <li> [sqlite3_uri_key()],
3919
** <li> [sqlite3_filename_database()],
3920
** <li> [sqlite3_filename_journal()], or
3921
** <li> [sqlite3_filename_wal()].
3922
** </ul>
3923
** If a memory allocation error occurs, sqlite3_create_filename() might
3924
** return a NULL pointer.  The memory obtained from sqlite3_create_filename(X)
3925
** must be released by a corresponding call to sqlite3_free_filename(Y).
3926
**
3927
** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array
3928
** of 2*N pointers to strings.  Each pair of pointers in this array corresponds
3929
** to a key and value for a query parameter.  The P parameter may be a NULL
3930
** pointer if N is zero.  None of the 2*N pointers in the P array may be
3931
** NULL pointers and key pointers should not be empty strings.
3932
** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may
3933
** be NULL pointers, though they can be empty strings.
3934
**
3935
** The sqlite3_free_filename(Y) routine releases a memory allocation
3936
** previously obtained from sqlite3_create_filename().  Invoking
3937
** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
3938
**
3939
** If the Y parameter to sqlite3_free_filename(Y) is anything other
3940
** than a NULL pointer or a pointer previously acquired from
3941
** sqlite3_create_filename(), then bad things such as heap
3942
** corruption or segfaults may occur. The value Y should not be
3943
** used again after sqlite3_free_filename(Y) has been called.  This means
3944
** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
3945
** then the corresponding [sqlite3_module.xClose() method should also be
3946
** invoked prior to calling sqlite3_free_filename(Y).
3947
*/
3948
SQLITE_API sqlite3_filename sqlite3_create_filename(
3949
  const char *zDatabase,
3950
  const char *zJournal,
3951
  const char *zWal,
3952
  int nParam,
3953
  const char **azParam
3954
);
3955
SQLITE_API void sqlite3_free_filename(sqlite3_filename);
3956
3957
/*
3958
** CAPI3REF: Error Codes And Messages
3959
** METHOD: sqlite3
3960
**
3961
** ^If the most recent sqlite3_* API call associated with
3962
** [database connection] D failed, then the sqlite3_errcode(D) interface
3963
** returns the numeric [result code] or [extended result code] for that
3964
** API call.
3965
** ^The sqlite3_extended_errcode()
3966
** interface is the same except that it always returns the
3967
** [extended result code] even when extended result codes are
3968
** disabled.
3969
**
3970
** The values returned by sqlite3_errcode() and/or
3971
** sqlite3_extended_errcode() might change with each API call.
3972
** Except, there are some interfaces that are guaranteed to never
3973
** change the value of the error code.  The error-code preserving
3974
** interfaces include the following:
3975
**
3976
** <ul>
3977
** <li> sqlite3_errcode()
3978
** <li> sqlite3_extended_errcode()
3979
** <li> sqlite3_errmsg()
3980
** <li> sqlite3_errmsg16()
3981
** <li> sqlite3_error_offset()
3982
** </ul>
3983
**
3984
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3985
** text that describes the error, as either UTF-8 or UTF-16 respectively,
3986
** or NULL if no error message is available.
3987
** (See how SQLite handles [invalid UTF] for exceptions to this rule.)
3988
** ^(Memory to hold the error message string is managed internally.
3989
** The application does not need to worry about freeing the result.
3990
** However, the error string might be overwritten or deallocated by
3991
** subsequent calls to other SQLite interface functions.)^
3992
**
3993
** ^The sqlite3_errstr(E) interface returns the English-language text
3994
** that describes the [result code] E, as UTF-8, or NULL if E is not an
3995
** result code for which a text error message is available.
3996
** ^(Memory to hold the error message string is managed internally
3997
** and must not be freed by the application)^.
3998
**
3999
** ^If the most recent error references a specific token in the input
4000
** SQL, the sqlite3_error_offset() interface returns the byte offset
4001
** of the start of that token.  ^The byte offset returned by
4002
** sqlite3_error_offset() assumes that the input SQL is UTF8.
4003
** ^If the most recent error does not reference a specific token in the input
4004
** SQL, then the sqlite3_error_offset() function returns -1.
4005
**
4006
** When the serialized [threading mode] is in use, it might be the
4007
** case that a second error occurs on a separate thread in between
4008
** the time of the first error and the call to these interfaces.
4009
** When that happens, the second error will be reported since these
4010
** interfaces always report the most recent result.  To avoid
4011
** this, each thread can obtain exclusive use of the [database connection] D
4012
** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
4013
** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
4014
** all calls to the interfaces listed here are completed.
4015
**
4016
** If an interface fails with SQLITE_MISUSE, that means the interface
4017
** was invoked incorrectly by the application.  In that case, the
4018
** error code and message may or may not be set.
4019
*/
4020
SQLITE_API int sqlite3_errcode(sqlite3 *db);
4021
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
4022
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
4023
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
4024
SQLITE_API const char *sqlite3_errstr(int);
4025
SQLITE_API int sqlite3_error_offset(sqlite3 *db);
4026
4027
/*
4028
** CAPI3REF: Prepared Statement Object
4029
** KEYWORDS: {prepared statement} {prepared statements}
4030
**
4031
** An instance of this object represents a single SQL statement that
4032
** has been compiled into binary form and is ready to be evaluated.
4033
**
4034
** Think of each SQL statement as a separate computer program.  The
4035
** original SQL text is source code.  A prepared statement object
4036
** is the compiled object code.  All SQL must be converted into a
4037
** prepared statement before it can be run.
4038
**
4039
** The life-cycle of a prepared statement object usually goes like this:
4040
**
4041
** <ol>
4042
** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
4043
** <li> Bind values to [parameters] using the sqlite3_bind_*()
4044
**      interfaces.
4045
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
4046
** <li> Reset the prepared statement using [sqlite3_reset()] then go back
4047
**      to step 2.  Do this zero or more times.
4048
** <li> Destroy the object using [sqlite3_finalize()].
4049
** </ol>
4050
*/
4051
typedef struct sqlite3_stmt sqlite3_stmt;
4052
4053
/*
4054
** CAPI3REF: Run-time Limits
4055
** METHOD: sqlite3
4056
**
4057
** ^(This interface allows the size of various constructs to be limited
4058
** on a connection by connection basis.  The first parameter is the
4059
** [database connection] whose limit is to be set or queried.  The
4060
** second parameter is one of the [limit categories] that define a
4061
** class of constructs to be size limited.  The third parameter is the
4062
** new limit for that construct.)^
4063
**
4064
** ^If the new limit is a negative number, the limit is unchanged.
4065
** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
4066
** [limits | hard upper bound]
4067
** set at compile-time by a C preprocessor macro called
4068
** [limits | SQLITE_MAX_<i>NAME</i>].
4069
** (The "_LIMIT_" in the name is changed to "_MAX_".))^
4070
** ^Attempts to increase a limit above its hard upper bound are
4071
** silently truncated to the hard upper bound.
4072
**
4073
** ^Regardless of whether or not the limit was changed, the
4074
** [sqlite3_limit()] interface returns the prior value of the limit.
4075
** ^Hence, to find the current value of a limit without changing it,
4076
** simply invoke this interface with the third parameter set to -1.
4077
**
4078
** Run-time limits are intended for use in applications that manage
4079
** both their own internal database and also databases that are controlled
4080
** by untrusted external sources.  An example application might be a
4081
** web browser that has its own databases for storing history and
4082
** separate databases controlled by JavaScript applications downloaded
4083
** off the Internet.  The internal databases can be given the
4084
** large, default limits.  Databases managed by external sources can
4085
** be given much smaller limits designed to prevent a denial of service
4086
** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
4087
** interface to further control untrusted SQL.  The size of the database
4088
** created by an untrusted script can be contained using the
4089
** [max_page_count] [PRAGMA].
4090
**
4091
** New run-time limit categories may be added in future releases.
4092
*/
4093
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
4094
4095
/*
4096
** CAPI3REF: Run-Time Limit Categories
4097
** KEYWORDS: {limit category} {*limit categories}
4098
**
4099
** These constants define various performance limits
4100
** that can be lowered at run-time using [sqlite3_limit()].
4101
** The synopsis of the meanings of the various limits is shown below.
4102
** Additional information is available at [limits | Limits in SQLite].
4103
**
4104
** <dl>
4105
** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
4106
** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
4107
**
4108
** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
4109
** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
4110
**
4111
** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
4112
** <dd>The maximum number of columns in a table definition or in the
4113
** result set of a [SELECT] or the maximum number of columns in an index
4114
** or in an ORDER BY or GROUP BY clause.</dd>)^
4115
**
4116
** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
4117
** <dd>The maximum depth of the parse tree on any expression.</dd>)^
4118
**
4119
** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
4120
** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
4121
**
4122
** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
4123
** <dd>The maximum number of instructions in a virtual machine program
4124
** used to implement an SQL statement.  If [sqlite3_prepare_v2()] or
4125
** the equivalent tries to allocate space for more than this many opcodes
4126
** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
4127
**
4128
** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
4129
** <dd>The maximum number of arguments on a function.</dd>)^
4130
**
4131
** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
4132
** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
4133
**
4134
** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
4135
** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
4136
** <dd>The maximum length of the pattern argument to the [LIKE] or
4137
** [GLOB] operators.</dd>)^
4138
**
4139
** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
4140
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
4141
** <dd>The maximum index number of any [parameter] in an SQL statement.)^
4142
**
4143
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
4144
** <dd>The maximum depth of recursion for triggers.</dd>)^
4145
**
4146
** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
4147
** <dd>The maximum number of auxiliary worker threads that a single
4148
** [prepared statement] may start.</dd>)^
4149
** </dl>
4150
*/
4151
#define SQLITE_LIMIT_LENGTH                    0
4152
#define SQLITE_LIMIT_SQL_LENGTH                1
4153
#define SQLITE_LIMIT_COLUMN                    2
4154
#define SQLITE_LIMIT_EXPR_DEPTH                3
4155
#define SQLITE_LIMIT_COMPOUND_SELECT           4
4156
#define SQLITE_LIMIT_VDBE_OP                   5
4157
#define SQLITE_LIMIT_FUNCTION_ARG              6
4158
#define SQLITE_LIMIT_ATTACHED                  7
4159
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
4160
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
4161
#define SQLITE_LIMIT_TRIGGER_DEPTH            10
4162
#define SQLITE_LIMIT_WORKER_THREADS           11
4163
4164
/*
4165
** CAPI3REF: Prepare Flags
4166
**
4167
** These constants define various flags that can be passed into
4168
** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
4169
** [sqlite3_prepare16_v3()] interfaces.
4170
**
4171
** New flags may be added in future releases of SQLite.
4172
**
4173
** <dl>
4174
** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
4175
** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
4176
** that the prepared statement will be retained for a long time and
4177
** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
4178
** and [sqlite3_prepare16_v3()] assume that the prepared statement will
4179
** be used just once or at most a few times and then destroyed using
4180
** [sqlite3_finalize()] relatively soon. The current implementation acts
4181
** on this hint by avoiding the use of [lookaside memory] so as not to
4182
** deplete the limited store of lookaside memory. Future versions of
4183
** SQLite may act on this hint differently.
4184
**
4185
** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt>
4186
** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used
4187
** to be required for any prepared statement that wanted to use the
4188
** [sqlite3_normalized_sql()] interface.  However, the
4189
** [sqlite3_normalized_sql()] interface is now available to all
4190
** prepared statements, regardless of whether or not they use this
4191
** flag.
4192
**
4193
** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt>
4194
** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler
4195
** to return an error (error code SQLITE_ERROR) if the statement uses
4196
** any virtual tables.
4197
** </dl>
4198
*/
4199
#define SQLITE_PREPARE_PERSISTENT              0x01
4200
#define SQLITE_PREPARE_NORMALIZE               0x02
4201
#define SQLITE_PREPARE_NO_VTAB                 0x04
4202
4203
/*
4204
** CAPI3REF: Compiling An SQL Statement
4205
** KEYWORDS: {SQL statement compiler}
4206
** METHOD: sqlite3
4207
** CONSTRUCTOR: sqlite3_stmt
4208
**
4209
** To execute an SQL statement, it must first be compiled into a byte-code
4210
** program using one of these routines.  Or, in other words, these routines
4211
** are constructors for the [prepared statement] object.
4212
**
4213
** The preferred routine to use is [sqlite3_prepare_v2()].  The
4214
** [sqlite3_prepare()] interface is legacy and should be avoided.
4215
** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
4216
** for special purposes.
4217
**
4218
** The use of the UTF-8 interfaces is preferred, as SQLite currently
4219
** does all parsing using UTF-8.  The UTF-16 interfaces are provided
4220
** as a convenience.  The UTF-16 interfaces work by converting the
4221
** input text into UTF-8, then invoking the corresponding UTF-8 interface.
4222
**
4223
** The first argument, "db", is a [database connection] obtained from a
4224
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
4225
** [sqlite3_open16()].  The database connection must not have been closed.
4226
**
4227
** The second argument, "zSql", is the statement to be compiled, encoded
4228
** as either UTF-8 or UTF-16.  The sqlite3_prepare(), sqlite3_prepare_v2(),
4229
** and sqlite3_prepare_v3()
4230
** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
4231
** and sqlite3_prepare16_v3() use UTF-16.
4232
**
4233
** ^If the nByte argument is negative, then zSql is read up to the
4234
** first zero terminator. ^If nByte is positive, then it is the maximum
4235
** number of bytes read from zSql.  When nByte is positive, zSql is read
4236
** up to the first zero terminator or until the nByte bytes have been read,
4237
** whichever comes first.  ^If nByte is zero, then no prepared
4238
** statement is generated.
4239
** If the caller knows that the supplied string is nul-terminated, then
4240
** there is a small performance advantage to passing an nByte parameter that
4241
** is the number of bytes in the input string <i>including</i>
4242
** the nul-terminator.
4243
** Note that nByte measure the length of the input in bytes, not
4244
** characters, even for the UTF-16 interfaces.
4245
**
4246
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
4247
** past the end of the first SQL statement in zSql.  These routines only
4248
** compile the first statement in zSql, so *pzTail is left pointing to
4249
** what remains uncompiled.
4250
**
4251
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
4252
** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
4253
** to NULL.  ^If the input text contains no SQL (if the input is an empty
4254
** string or a comment) then *ppStmt is set to NULL.
4255
** The calling procedure is responsible for deleting the compiled
4256
** SQL statement using [sqlite3_finalize()] after it has finished with it.
4257
** ppStmt may not be NULL.
4258
**
4259
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
4260
** otherwise an [error code] is returned.
4261
**
4262
** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
4263
** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
4264
** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
4265
** are retained for backwards compatibility, but their use is discouraged.
4266
** ^In the "vX" interfaces, the prepared statement
4267
** that is returned (the [sqlite3_stmt] object) contains a copy of the
4268
** original SQL text. This causes the [sqlite3_step()] interface to
4269
** behave differently in three ways:
4270
**
4271
** <ol>
4272
** <li>
4273
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
4274
** always used to do, [sqlite3_step()] will automatically recompile the SQL
4275
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
4276
** retries will occur before sqlite3_step() gives up and returns an error.
4277
** </li>
4278
**
4279
** <li>
4280
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
4281
** [error codes] or [extended error codes].  ^The legacy behavior was that
4282
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
4283
** and the application would have to make a second call to [sqlite3_reset()]
4284
** in order to find the underlying cause of the problem. With the "v2" prepare
4285
** interfaces, the underlying reason for the error is returned immediately.
4286
** </li>
4287
**
4288
** <li>
4289
** ^If the specific value bound to a [parameter | host parameter] in the
4290
** WHERE clause might influence the choice of query plan for a statement,
4291
** then the statement will be automatically recompiled, as if there had been
4292
** a schema change, on the first [sqlite3_step()] call following any change
4293
** to the [sqlite3_bind_text | bindings] of that [parameter].
4294
** ^The specific value of a WHERE-clause [parameter] might influence the
4295
** choice of query plan if the parameter is the left-hand side of a [LIKE]
4296
** or [GLOB] operator or if the parameter is compared to an indexed column
4297
** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled.
4298
** </li>
4299
** </ol>
4300
**
4301
** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
4302
** the extra prepFlags parameter, which is a bit array consisting of zero or
4303
** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags.  ^The
4304
** sqlite3_prepare_v2() interface works exactly the same as
4305
** sqlite3_prepare_v3() with a zero prepFlags parameter.
4306
*/
4307
SQLITE_API int sqlite3_prepare(
4308
  sqlite3 *db,            /* Database handle */
4309
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4310
  int nByte,              /* Maximum length of zSql in bytes. */
4311
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4312
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4313
);
4314
SQLITE_API int sqlite3_prepare_v2(
4315
  sqlite3 *db,            /* Database handle */
4316
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4317
  int nByte,              /* Maximum length of zSql in bytes. */
4318
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4319
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4320
);
4321
SQLITE_API int sqlite3_prepare_v3(
4322
  sqlite3 *db,            /* Database handle */
4323
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4324
  int nByte,              /* Maximum length of zSql in bytes. */
4325
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4326
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4327
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4328
);
4329
SQLITE_API int sqlite3_prepare16(
4330
  sqlite3 *db,            /* Database handle */
4331
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4332
  int nByte,              /* Maximum length of zSql in bytes. */
4333
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4334
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4335
);
4336
SQLITE_API int sqlite3_prepare16_v2(
4337
  sqlite3 *db,            /* Database handle */
4338
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4339
  int nByte,              /* Maximum length of zSql in bytes. */
4340
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4341
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4342
);
4343
SQLITE_API int sqlite3_prepare16_v3(
4344
  sqlite3 *db,            /* Database handle */
4345
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4346
  int nByte,              /* Maximum length of zSql in bytes. */
4347
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4348
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4349
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4350
);
4351
4352
/*
4353
** CAPI3REF: Retrieving Statement SQL
4354
** METHOD: sqlite3_stmt
4355
**
4356
** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
4357
** SQL text used to create [prepared statement] P if P was
4358
** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
4359
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4360
** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
4361
** string containing the SQL text of prepared statement P with
4362
** [bound parameters] expanded.
4363
** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8
4364
** string containing the normalized SQL text of prepared statement P.  The
4365
** semantics used to normalize a SQL statement are unspecified and subject
4366
** to change.  At a minimum, literal values will be replaced with suitable
4367
** placeholders.
4368
**
4369
** ^(For example, if a prepared statement is created using the SQL
4370
** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
4371
** and parameter :xyz is unbound, then sqlite3_sql() will return
4372
** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
4373
** will return "SELECT 2345,NULL".)^
4374
**
4375
** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
4376
** is available to hold the result, or if the result would exceed the
4377
** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
4378
**
4379
** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
4380
** bound parameter expansions.  ^The [SQLITE_OMIT_TRACE] compile-time
4381
** option causes sqlite3_expanded_sql() to always return NULL.
4382
**
4383
** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P)
4384
** are managed by SQLite and are automatically freed when the prepared
4385
** statement is finalized.
4386
** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
4387
** is obtained from [sqlite3_malloc()] and must be freed by the application
4388
** by passing it to [sqlite3_free()].
4389
**
4390
** ^The sqlite3_normalized_sql() interface is only available if
4391
** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined.
4392
*/
4393
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
4394
SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
4395
#ifdef SQLITE_ENABLE_NORMALIZE
4396
SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt);
4397
#endif
4398
4399
/*
4400
** CAPI3REF: Determine If An SQL Statement Writes The Database
4401
** METHOD: sqlite3_stmt
4402
**
4403
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
4404
** and only if the [prepared statement] X makes no direct changes to
4405
** the content of the database file.
4406
**
4407
** Note that [application-defined SQL functions] or
4408
** [virtual tables] might change the database indirectly as a side effect.
4409
** ^(For example, if an application defines a function "eval()" that
4410
** calls [sqlite3_exec()], then the following SQL statement would
4411
** change the database file through side-effects:
4412
**
4413
** <blockquote><pre>
4414
**    SELECT eval('DELETE FROM t1') FROM t2;
4415
** </pre></blockquote>
4416
**
4417
** But because the [SELECT] statement does not change the database file
4418
** directly, sqlite3_stmt_readonly() would still return true.)^
4419
**
4420
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
4421
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
4422
** since the statements themselves do not actually modify the database but
4423
** rather they control the timing of when other statements modify the
4424
** database.  ^The [ATTACH] and [DETACH] statements also cause
4425
** sqlite3_stmt_readonly() to return true since, while those statements
4426
** change the configuration of a database connection, they do not make
4427
** changes to the content of the database files on disk.
4428
** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
4429
** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
4430
** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
4431
** sqlite3_stmt_readonly() returns false for those commands.
4432
**
4433
** ^This routine returns false if there is any possibility that the
4434
** statement might change the database file.  ^A false return does
4435
** not guarantee that the statement will change the database file.
4436
** ^For example, an UPDATE statement might have a WHERE clause that
4437
** makes it a no-op, but the sqlite3_stmt_readonly() result would still
4438
** be false.  ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a
4439
** read-only no-op if the table already exists, but
4440
** sqlite3_stmt_readonly() still returns false for such a statement.
4441
**
4442
** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN]
4443
** statement, then sqlite3_stmt_readonly(X) returns the same value as
4444
** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted.
4445
*/
4446
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
4447
4448
/*
4449
** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
4450
** METHOD: sqlite3_stmt
4451
**
4452
** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
4453
** prepared statement S is an EXPLAIN statement, or 2 if the
4454
** statement S is an EXPLAIN QUERY PLAN.
4455
** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
4456
** an ordinary statement or a NULL pointer.
4457
*/
4458
SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);
4459
4460
/*
4461
** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement
4462
** METHOD: sqlite3_stmt
4463
**
4464
** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN
4465
** setting for [prepared statement] S.  If E is zero, then S becomes
4466
** a normal prepared statement.  If E is 1, then S behaves as if
4467
** its SQL text began with "[EXPLAIN]".  If E is 2, then S behaves as if
4468
** its SQL text began with "[EXPLAIN QUERY PLAN]".
4469
**
4470
** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared.
4471
** SQLite tries to avoid a reprepare, but a reprepare might be necessary
4472
** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode.
4473
**
4474
** Because of the potential need to reprepare, a call to
4475
** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be
4476
** reprepared because it was created using [sqlite3_prepare()] instead of
4477
** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and
4478
** hence has no saved SQL text with which to reprepare.
4479
**
4480
** Changing the explain setting for a prepared statement does not change
4481
** the original SQL text for the statement.  Hence, if the SQL text originally
4482
** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0)
4483
** is called to convert the statement into an ordinary statement, the EXPLAIN
4484
** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S)
4485
** output, even though the statement now acts like a normal SQL statement.
4486
**
4487
** This routine returns SQLITE_OK if the explain mode is successfully
4488
** changed, or an error code if the explain mode could not be changed.
4489
** The explain mode cannot be changed while a statement is active.
4490
** Hence, it is good practice to call [sqlite3_reset(S)]
4491
** immediately prior to calling sqlite3_stmt_explain(S,E).
4492
*/
4493
SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode);
4494
4495
/*
4496
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
4497
** METHOD: sqlite3_stmt
4498
**
4499
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
4500
** [prepared statement] S has been stepped at least once using
4501
** [sqlite3_step(S)] but has neither run to completion (returned
4502
** [SQLITE_DONE] from [sqlite3_step(S)]) nor
4503
** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
4504
** interface returns false if S is a NULL pointer.  If S is not a
4505
** NULL pointer and is not a pointer to a valid [prepared statement]
4506
** object, then the behavior is undefined and probably undesirable.
4507
**
4508
** This interface can be used in combination [sqlite3_next_stmt()]
4509
** to locate all prepared statements associated with a database
4510
** connection that are in need of being reset.  This can be used,
4511
** for example, in diagnostic routines to search for prepared
4512
** statements that are holding a transaction open.
4513
*/
4514
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
4515
4516
/*
4517
** CAPI3REF: Dynamically Typed Value Object
4518
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
4519
**
4520
** SQLite uses the sqlite3_value object to represent all values
4521
** that can be stored in a database table. SQLite uses dynamic typing
4522
** for the values it stores.  ^Values stored in sqlite3_value objects
4523
** can be integers, floating point values, strings, BLOBs, or NULL.
4524
**
4525
** An sqlite3_value object may be either "protected" or "unprotected".
4526
** Some interfaces require a protected sqlite3_value.  Other interfaces
4527
** will accept either a protected or an unprotected sqlite3_value.
4528
** Every interface that accepts sqlite3_value arguments specifies
4529
** whether or not it requires a protected sqlite3_value.  The
4530
** [sqlite3_value_dup()] interface can be used to construct a new
4531
** protected sqlite3_value from an unprotected sqlite3_value.
4532
**
4533
** The terms "protected" and "unprotected" refer to whether or not
4534
** a mutex is held.  An internal mutex is held for a protected
4535
** sqlite3_value object but no mutex is held for an unprotected
4536
** sqlite3_value object.  If SQLite is compiled to be single-threaded
4537
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
4538
** or if SQLite is run in one of reduced mutex modes
4539
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
4540
** then there is no distinction between protected and unprotected
4541
** sqlite3_value objects and they can be used interchangeably.  However,
4542
** for maximum code portability it is recommended that applications
4543
** still make the distinction between protected and unprotected
4544
** sqlite3_value objects even when not strictly required.
4545
**
4546
** ^The sqlite3_value objects that are passed as parameters into the
4547
** implementation of [application-defined SQL functions] are protected.
4548
** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()]
4549
** are protected.
4550
** ^The sqlite3_value object returned by
4551
** [sqlite3_column_value()] is unprotected.
4552
** Unprotected sqlite3_value objects may only be used as arguments
4553
** to [sqlite3_result_value()], [sqlite3_bind_value()], and
4554
** [sqlite3_value_dup()].
4555
** The [sqlite3_value_blob | sqlite3_value_type()] family of
4556
** interfaces require protected sqlite3_value objects.
4557
*/
4558
typedef struct sqlite3_value sqlite3_value;
4559
4560
/*
4561
** CAPI3REF: SQL Function Context Object
4562
**
4563
** The context in which an SQL function executes is stored in an
4564
** sqlite3_context object.  ^A pointer to an sqlite3_context object
4565
** is always first parameter to [application-defined SQL functions].
4566
** The application-defined SQL function implementation will pass this
4567
** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
4568
** [sqlite3_aggregate_context()], [sqlite3_user_data()],
4569
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
4570
** and/or [sqlite3_set_auxdata()].
4571
*/
4572
typedef struct sqlite3_context sqlite3_context;
4573
4574
/*
4575
** CAPI3REF: Binding Values To Prepared Statements
4576
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
4577
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
4578
** METHOD: sqlite3_stmt
4579
**
4580
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
4581
** literals may be replaced by a [parameter] that matches one of following
4582
** templates:
4583
**
4584
** <ul>
4585
** <li>  ?
4586
** <li>  ?NNN
4587
** <li>  :VVV
4588
** <li>  @VVV
4589
** <li>  $VVV
4590
** </ul>
4591
**
4592
** In the templates above, NNN represents an integer literal,
4593
** and VVV represents an alphanumeric identifier.)^  ^The values of these
4594
** parameters (also called "host parameter names" or "SQL parameters")
4595
** can be set using the sqlite3_bind_*() routines defined here.
4596
**
4597
** ^The first argument to the sqlite3_bind_*() routines is always
4598
** a pointer to the [sqlite3_stmt] object returned from
4599
** [sqlite3_prepare_v2()] or its variants.
4600
**
4601
** ^The second argument is the index of the SQL parameter to be set.
4602
** ^The leftmost SQL parameter has an index of 1.  ^When the same named
4603
** SQL parameter is used more than once, second and subsequent
4604
** occurrences have the same index as the first occurrence.
4605
** ^The index for named parameters can be looked up using the
4606
** [sqlite3_bind_parameter_index()] API if desired.  ^The index
4607
** for "?NNN" parameters is the value of NNN.
4608
** ^The NNN value must be between 1 and the [sqlite3_limit()]
4609
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766).
4610
**
4611
** ^The third argument is the value to bind to the parameter.
4612
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4613
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
4614
** is ignored and the end result is the same as sqlite3_bind_null().
4615
** ^If the third parameter to sqlite3_bind_text() is not NULL, then
4616
** it should be a pointer to well-formed UTF8 text.
4617
** ^If the third parameter to sqlite3_bind_text16() is not NULL, then
4618
** it should be a pointer to well-formed UTF16 text.
4619
** ^If the third parameter to sqlite3_bind_text64() is not NULL, then
4620
** it should be a pointer to a well-formed unicode string that is
4621
** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16
4622
** otherwise.
4623
**
4624
** [[byte-order determination rules]] ^The byte-order of
4625
** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF)
4626
** found in first character, which is removed, or in the absence of a BOM
4627
** the byte order is the native byte order of the host
4628
** machine for sqlite3_bind_text16() or the byte order specified in
4629
** the 6th parameter for sqlite3_bind_text64().)^
4630
** ^If UTF16 input text contains invalid unicode
4631
** characters, then SQLite might change those invalid characters
4632
** into the unicode replacement character: U+FFFD.
4633
**
4634
** ^(In those routines that have a fourth argument, its value is the
4635
** number of bytes in the parameter.  To be clear: the value is the
4636
** number of <u>bytes</u> in the value, not the number of characters.)^
4637
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4638
** is negative, then the length of the string is
4639
** the number of bytes up to the first zero terminator.
4640
** If the fourth parameter to sqlite3_bind_blob() is negative, then
4641
** the behavior is undefined.
4642
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
4643
** or sqlite3_bind_text16() or sqlite3_bind_text64() then
4644
** that parameter must be the byte offset
4645
** where the NUL terminator would occur assuming the string were NUL
4646
** terminated.  If any NUL characters occurs at byte offsets less than
4647
** the value of the fourth parameter then the resulting string value will
4648
** contain embedded NULs.  The result of expressions involving strings
4649
** with embedded NULs is undefined.
4650
**
4651
** ^The fifth argument to the BLOB and string binding interfaces controls
4652
** or indicates the lifetime of the object referenced by the third parameter.
4653
** These three options exist:
4654
** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished
4655
** with it may be passed. ^It is called to dispose of the BLOB or string even
4656
** if the call to the bind API fails, except the destructor is not called if
4657
** the third parameter is a NULL pointer or the fourth parameter is negative.
4658
** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that
4659
** the application remains responsible for disposing of the object. ^In this
4660
** case, the object and the provided pointer to it must remain valid until
4661
** either the prepared statement is finalized or the same SQL parameter is
4662
** bound to something else, whichever occurs sooner.
4663
** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the
4664
** object is to be copied prior to the return from sqlite3_bind_*(). ^The
4665
** object and pointer to it must remain valid until then. ^SQLite will then
4666
** manage the lifetime of its private copy.
4667
**
4668
** ^The sixth argument to sqlite3_bind_text64() must be one of
4669
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
4670
** to specify the encoding of the text in the third parameter.  If
4671
** the sixth argument to sqlite3_bind_text64() is not one of the
4672
** allowed values shown above, or if the text encoding is different
4673
** from the encoding specified by the sixth parameter, then the behavior
4674
** is undefined.
4675
**
4676
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
4677
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
4678
** (just an integer to hold its size) while it is being processed.
4679
** Zeroblobs are intended to serve as placeholders for BLOBs whose
4680
** content is later written using
4681
** [sqlite3_blob_open | incremental BLOB I/O] routines.
4682
** ^A negative value for the zeroblob results in a zero-length BLOB.
4683
**
4684
** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
4685
** [prepared statement] S to have an SQL value of NULL, but to also be
4686
** associated with the pointer P of type T.  ^D is either a NULL pointer or
4687
** a pointer to a destructor function for P. ^SQLite will invoke the
4688
** destructor D with a single argument of P when it is finished using
4689
** P.  The T parameter should be a static string, preferably a string
4690
** literal. The sqlite3_bind_pointer() routine is part of the
4691
** [pointer passing interface] added for SQLite 3.20.0.
4692
**
4693
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
4694
** for the [prepared statement] or with a prepared statement for which
4695
** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
4696
** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
4697
** routine is passed a [prepared statement] that has been finalized, the
4698
** result is undefined and probably harmful.
4699
**
4700
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
4701
** ^Unbound parameters are interpreted as NULL.
4702
**
4703
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
4704
** [error code] if anything goes wrong.
4705
** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
4706
** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
4707
** [SQLITE_MAX_LENGTH].
4708
** ^[SQLITE_RANGE] is returned if the parameter
4709
** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
4710
**
4711
** See also: [sqlite3_bind_parameter_count()],
4712
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
4713
*/
4714
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
4715
SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
4716
                        void(*)(void*));
4717
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
4718
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
4719
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
4720
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
4721
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
4722
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
4723
SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
4724
                         void(*)(void*), unsigned char encoding);
4725
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
4726
SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
4727
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
4728
SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
4729
4730
/*
4731
** CAPI3REF: Number Of SQL Parameters
4732
** METHOD: sqlite3_stmt
4733
**
4734
** ^This routine can be used to find the number of [SQL parameters]
4735
** in a [prepared statement].  SQL parameters are tokens of the
4736
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
4737
** placeholders for values that are [sqlite3_bind_blob | bound]
4738
** to the parameters at a later time.
4739
**
4740
** ^(This routine actually returns the index of the largest (rightmost)
4741
** parameter. For all forms except ?NNN, this will correspond to the
4742
** number of unique parameters.  If parameters of the ?NNN form are used,
4743
** there may be gaps in the list.)^
4744
**
4745
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4746
** [sqlite3_bind_parameter_name()], and
4747
** [sqlite3_bind_parameter_index()].
4748
*/
4749
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
4750
4751
/*
4752
** CAPI3REF: Name Of A Host Parameter
4753
** METHOD: sqlite3_stmt
4754
**
4755
** ^The sqlite3_bind_parameter_name(P,N) interface returns
4756
** the name of the N-th [SQL parameter] in the [prepared statement] P.
4757
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
4758
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
4759
** respectively.
4760
** In other words, the initial ":" or "$" or "@" or "?"
4761
** is included as part of the name.)^
4762
** ^Parameters of the form "?" without a following integer have no name
4763
** and are referred to as "nameless" or "anonymous parameters".
4764
**
4765
** ^The first host parameter has an index of 1, not 0.
4766
**
4767
** ^If the value N is out of range or if the N-th parameter is
4768
** nameless, then NULL is returned.  ^The returned string is
4769
** always in UTF-8 encoding even if the named parameter was
4770
** originally specified as UTF-16 in [sqlite3_prepare16()],
4771
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4772
**
4773
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4774
** [sqlite3_bind_parameter_count()], and
4775
** [sqlite3_bind_parameter_index()].
4776
*/
4777
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
4778
4779
/*
4780
** CAPI3REF: Index Of A Parameter With A Given Name
4781
** METHOD: sqlite3_stmt
4782
**
4783
** ^Return the index of an SQL parameter given its name.  ^The
4784
** index value returned is suitable for use as the second
4785
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
4786
** is returned if no matching parameter is found.  ^The parameter
4787
** name must be given in UTF-8 even if the original statement
4788
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
4789
** [sqlite3_prepare16_v3()].
4790
**
4791
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4792
** [sqlite3_bind_parameter_count()], and
4793
** [sqlite3_bind_parameter_name()].
4794
*/
4795
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
4796
4797
/*
4798
** CAPI3REF: Reset All Bindings On A Prepared Statement
4799
** METHOD: sqlite3_stmt
4800
**
4801
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
4802
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
4803
** ^Use this routine to reset all host parameters to NULL.
4804
*/
4805
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
4806
4807
/*
4808
** CAPI3REF: Number Of Columns In A Result Set
4809
** METHOD: sqlite3_stmt
4810
**
4811
** ^Return the number of columns in the result set returned by the
4812
** [prepared statement]. ^If this routine returns 0, that means the
4813
** [prepared statement] returns no data (for example an [UPDATE]).
4814
** ^However, just because this routine returns a positive number does not
4815
** mean that one or more rows of data will be returned.  ^A SELECT statement
4816
** will always have a positive sqlite3_column_count() but depending on the
4817
** WHERE clause constraints and the table content, it might return no rows.
4818
**
4819
** See also: [sqlite3_data_count()]
4820
*/
4821
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
4822
4823
/*
4824
** CAPI3REF: Column Names In A Result Set
4825
** METHOD: sqlite3_stmt
4826
**
4827
** ^These routines return the name assigned to a particular column
4828
** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
4829
** interface returns a pointer to a zero-terminated UTF-8 string
4830
** and sqlite3_column_name16() returns a pointer to a zero-terminated
4831
** UTF-16 string.  ^The first parameter is the [prepared statement]
4832
** that implements the [SELECT] statement. ^The second parameter is the
4833
** column number.  ^The leftmost column is number 0.
4834
**
4835
** ^The returned string pointer is valid until either the [prepared statement]
4836
** is destroyed by [sqlite3_finalize()] or until the statement is automatically
4837
** reprepared by the first call to [sqlite3_step()] for a particular run
4838
** or until the next call to
4839
** sqlite3_column_name() or sqlite3_column_name16() on the same column.
4840
**
4841
** ^If sqlite3_malloc() fails during the processing of either routine
4842
** (for example during a conversion from UTF-8 to UTF-16) then a
4843
** NULL pointer is returned.
4844
**
4845
** ^The name of a result column is the value of the "AS" clause for
4846
** that column, if there is an AS clause.  If there is no AS clause
4847
** then the name of the column is unspecified and may change from
4848
** one release of SQLite to the next.
4849
*/
4850
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
4851
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
4852
4853
/*
4854
** CAPI3REF: Source Of Data In A Query Result
4855
** METHOD: sqlite3_stmt
4856
**
4857
** ^These routines provide a means to determine the database, table, and
4858
** table column that is the origin of a particular result column in
4859
** [SELECT] statement.
4860
** ^The name of the database or table or column can be returned as
4861
** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
4862
** the database name, the _table_ routines return the table name, and
4863
** the origin_ routines return the column name.
4864
** ^The returned string is valid until the [prepared statement] is destroyed
4865
** using [sqlite3_finalize()] or until the statement is automatically
4866
** reprepared by the first call to [sqlite3_step()] for a particular run
4867
** or until the same information is requested
4868
** again in a different encoding.
4869
**
4870
** ^The names returned are the original un-aliased names of the
4871
** database, table, and column.
4872
**
4873
** ^The first argument to these interfaces is a [prepared statement].
4874
** ^These functions return information about the Nth result column returned by
4875
** the statement, where N is the second function argument.
4876
** ^The left-most column is column 0 for these routines.
4877
**
4878
** ^If the Nth column returned by the statement is an expression or
4879
** subquery and is not a column value, then all of these functions return
4880
** NULL.  ^These routines might also return NULL if a memory allocation error
4881
** occurs.  ^Otherwise, they return the name of the attached database, table,
4882
** or column that query result column was extracted from.
4883
**
4884
** ^As with all other SQLite APIs, those whose names end with "16" return
4885
** UTF-16 encoded strings and the other functions return UTF-8.
4886
**
4887
** ^These APIs are only available if the library was compiled with the
4888
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
4889
**
4890
** If two or more threads call one or more
4891
** [sqlite3_column_database_name | column metadata interfaces]
4892
** for the same [prepared statement] and result column
4893
** at the same time then the results are undefined.
4894
*/
4895
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
4896
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
4897
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
4898
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
4899
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
4900
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
4901
4902
/*
4903
** CAPI3REF: Declared Datatype Of A Query Result
4904
** METHOD: sqlite3_stmt
4905
**
4906
** ^(The first parameter is a [prepared statement].
4907
** If this statement is a [SELECT] statement and the Nth column of the
4908
** returned result set of that [SELECT] is a table column (not an
4909
** expression or subquery) then the declared type of the table
4910
** column is returned.)^  ^If the Nth column of the result set is an
4911
** expression or subquery, then a NULL pointer is returned.
4912
** ^The returned string is always UTF-8 encoded.
4913
**
4914
** ^(For example, given the database schema:
4915
**
4916
** CREATE TABLE t1(c1 VARIANT);
4917
**
4918
** and the following statement to be compiled:
4919
**
4920
** SELECT c1 + 1, c1 FROM t1;
4921
**
4922
** this routine would return the string "VARIANT" for the second result
4923
** column (i==1), and a NULL pointer for the first result column (i==0).)^
4924
**
4925
** ^SQLite uses dynamic run-time typing.  ^So just because a column
4926
** is declared to contain a particular type does not mean that the
4927
** data stored in that column is of the declared type.  SQLite is
4928
** strongly typed, but the typing is dynamic not static.  ^Type
4929
** is associated with individual values, not with the containers
4930
** used to hold those values.
4931
*/
4932
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
4933
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
4934
4935
/*
4936
** CAPI3REF: Evaluate An SQL Statement
4937
** METHOD: sqlite3_stmt
4938
**
4939
** After a [prepared statement] has been prepared using any of
4940
** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
4941
** or [sqlite3_prepare16_v3()] or one of the legacy
4942
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
4943
** must be called one or more times to evaluate the statement.
4944
**
4945
** The details of the behavior of the sqlite3_step() interface depend
4946
** on whether the statement was prepared using the newer "vX" interfaces
4947
** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
4948
** [sqlite3_prepare16_v2()] or the older legacy
4949
** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
4950
** new "vX" interface is recommended for new applications but the legacy
4951
** interface will continue to be supported.
4952
**
4953
** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
4954
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
4955
** ^With the "v2" interface, any of the other [result codes] or
4956
** [extended result codes] might be returned as well.
4957
**
4958
** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
4959
** database locks it needs to do its job.  ^If the statement is a [COMMIT]
4960
** or occurs outside of an explicit transaction, then you can retry the
4961
** statement.  If the statement is not a [COMMIT] and occurs within an
4962
** explicit transaction then you should rollback the transaction before
4963
** continuing.
4964
**
4965
** ^[SQLITE_DONE] means that the statement has finished executing
4966
** successfully.  sqlite3_step() should not be called again on this virtual
4967
** machine without first calling [sqlite3_reset()] to reset the virtual
4968
** machine back to its initial state.
4969
**
4970
** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
4971
** is returned each time a new row of data is ready for processing by the
4972
** caller. The values may be accessed using the [column access functions].
4973
** sqlite3_step() is called again to retrieve the next row of data.
4974
**
4975
** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
4976
** violation) has occurred.  sqlite3_step() should not be called again on
4977
** the VM. More information may be found by calling [sqlite3_errmsg()].
4978
** ^With the legacy interface, a more specific error code (for example,
4979
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
4980
** can be obtained by calling [sqlite3_reset()] on the
4981
** [prepared statement].  ^In the "v2" interface,
4982
** the more specific error code is returned directly by sqlite3_step().
4983
**
4984
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
4985
** Perhaps it was called on a [prepared statement] that has
4986
** already been [sqlite3_finalize | finalized] or on one that had
4987
** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
4988
** be the case that the same database connection is being used by two or
4989
** more threads at the same moment in time.
4990
**
4991
** For all versions of SQLite up to and including 3.6.23.1, a call to
4992
** [sqlite3_reset()] was required after sqlite3_step() returned anything
4993
** other than [SQLITE_ROW] before any subsequent invocation of
4994
** sqlite3_step().  Failure to reset the prepared statement using
4995
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
4996
** sqlite3_step().  But after [version 3.6.23.1] ([dateof:3.6.23.1],
4997
** sqlite3_step() began
4998
** calling [sqlite3_reset()] automatically in this circumstance rather
4999
** than returning [SQLITE_MISUSE].  This is not considered a compatibility
5000
** break because any application that ever receives an SQLITE_MISUSE error
5001
** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
5002
** can be used to restore the legacy behavior.
5003
**
5004
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
5005
** API always returns a generic error code, [SQLITE_ERROR], following any
5006
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
5007
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
5008
** specific [error codes] that better describes the error.
5009
** We admit that this is a goofy design.  The problem has been fixed
5010
** with the "v2" interface.  If you prepare all of your SQL statements
5011
** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
5012
** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
5013
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
5014
** then the more specific [error codes] are returned directly
5015
** by sqlite3_step().  The use of the "vX" interfaces is recommended.
5016
*/
5017
SQLITE_API int sqlite3_step(sqlite3_stmt*);
5018
5019
/*
5020
** CAPI3REF: Number of columns in a result set
5021
** METHOD: sqlite3_stmt
5022
**
5023
** ^The sqlite3_data_count(P) interface returns the number of columns in the
5024
** current row of the result set of [prepared statement] P.
5025
** ^If prepared statement P does not have results ready to return
5026
** (via calls to the [sqlite3_column_int | sqlite3_column()] family of
5027
** interfaces) then sqlite3_data_count(P) returns 0.
5028
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
5029
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
5030
** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
5031
** will return non-zero if previous call to [sqlite3_step](P) returned
5032
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
5033
** where it always returns zero since each step of that multi-step
5034
** pragma returns 0 columns of data.
5035
**
5036
** See also: [sqlite3_column_count()]
5037
*/
5038
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
5039
5040
/*
5041
** CAPI3REF: Fundamental Datatypes
5042
** KEYWORDS: SQLITE_TEXT
5043
**
5044
** ^(Every value in SQLite has one of five fundamental datatypes:
5045
**
5046
** <ul>
5047
** <li> 64-bit signed integer
5048
** <li> 64-bit IEEE floating point number
5049
** <li> string
5050
** <li> BLOB
5051
** <li> NULL
5052
** </ul>)^
5053
**
5054
** These constants are codes for each of those types.
5055
**
5056
** Note that the SQLITE_TEXT constant was also used in SQLite version 2
5057
** for a completely different meaning.  Software that links against both
5058
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
5059
** SQLITE_TEXT.
5060
*/
5061
#define SQLITE_INTEGER  1
5062
#define SQLITE_FLOAT    2
5063
#define SQLITE_BLOB     4
5064
#define SQLITE_NULL     5
5065
#ifdef SQLITE_TEXT
5066
# undef SQLITE_TEXT
5067
#else
5068
# define SQLITE_TEXT     3
5069
#endif
5070
#define SQLITE3_TEXT     3
5071
5072
/*
5073
** CAPI3REF: Result Values From A Query
5074
** KEYWORDS: {column access functions}
5075
** METHOD: sqlite3_stmt
5076
**
5077
** <b>Summary:</b>
5078
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5079
** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
5080
** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
5081
** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
5082
** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
5083
** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
5084
** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
5085
** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an
5086
** [sqlite3_value|unprotected sqlite3_value] object.
5087
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
5088
** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
5089
** or a UTF-8 TEXT result in bytes
5090
** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
5091
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
5092
** TEXT in bytes
5093
** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
5094
** datatype of the result
5095
** </table></blockquote>
5096
**
5097
** <b>Details:</b>
5098
**
5099
** ^These routines return information about a single column of the current
5100
** result row of a query.  ^In every case the first argument is a pointer
5101
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
5102
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
5103
** and the second argument is the index of the column for which information
5104
** should be returned. ^The leftmost column of the result set has the index 0.
5105
** ^The number of columns in the result can be determined using
5106
** [sqlite3_column_count()].
5107
**
5108
** If the SQL statement does not currently point to a valid row, or if the
5109
** column index is out of range, the result is undefined.
5110
** These routines may only be called when the most recent call to
5111
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
5112
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
5113
** If any of these routines are called after [sqlite3_reset()] or
5114
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
5115
** something other than [SQLITE_ROW], the results are undefined.
5116
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
5117
** are called from a different thread while any of these routines
5118
** are pending, then the results are undefined.
5119
**
5120
** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
5121
** each return the value of a result column in a specific data format.  If
5122
** the result column is not initially in the requested format (for example,
5123
** if the query returns an integer but the sqlite3_column_text() interface
5124
** is used to extract the value) then an automatic type conversion is performed.
5125
**
5126
** ^The sqlite3_column_type() routine returns the
5127
** [SQLITE_INTEGER | datatype code] for the initial data type
5128
** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
5129
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
5130
** The return value of sqlite3_column_type() can be used to decide which
5131
** of the first six interface should be used to extract the column value.
5132
** The value returned by sqlite3_column_type() is only meaningful if no
5133
** automatic type conversions have occurred for the value in question.
5134
** After a type conversion, the result of calling sqlite3_column_type()
5135
** is undefined, though harmless.  Future
5136
** versions of SQLite may change the behavior of sqlite3_column_type()
5137
** following a type conversion.
5138
**
5139
** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
5140
** or sqlite3_column_bytes16() interfaces can be used to determine the size
5141
** of that BLOB or string.
5142
**
5143
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
5144
** routine returns the number of bytes in that BLOB or string.
5145
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
5146
** the string to UTF-8 and then returns the number of bytes.
5147
** ^If the result is a numeric value then sqlite3_column_bytes() uses
5148
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
5149
** the number of bytes in that string.
5150
** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
5151
**
5152
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
5153
** routine returns the number of bytes in that BLOB or string.
5154
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
5155
** the string to UTF-16 and then returns the number of bytes.
5156
** ^If the result is a numeric value then sqlite3_column_bytes16() uses
5157
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
5158
** the number of bytes in that string.
5159
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
5160
**
5161
** ^The values returned by [sqlite3_column_bytes()] and
5162
** [sqlite3_column_bytes16()] do not include the zero terminators at the end
5163
** of the string.  ^For clarity: the values returned by
5164
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
5165
** bytes in the string, not the number of characters.
5166
**
5167
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
5168
** even empty strings, are always zero-terminated.  ^The return
5169
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
5170
**
5171
** ^Strings returned by sqlite3_column_text16() always have the endianness
5172
** which is native to the platform, regardless of the text encoding set
5173
** for the database.
5174
**
5175
** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
5176
** [unprotected sqlite3_value] object.  In a multithreaded environment,
5177
** an unprotected sqlite3_value object may only be used safely with
5178
** [sqlite3_bind_value()] and [sqlite3_result_value()].
5179
** If the [unprotected sqlite3_value] object returned by
5180
** [sqlite3_column_value()] is used in any other way, including calls
5181
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
5182
** or [sqlite3_value_bytes()], the behavior is not threadsafe.
5183
** Hence, the sqlite3_column_value() interface
5184
** is normally only useful within the implementation of
5185
** [application-defined SQL functions] or [virtual tables], not within
5186
** top-level application code.
5187
**
5188
** These routines may attempt to convert the datatype of the result.
5189
** ^For example, if the internal representation is FLOAT and a text result
5190
** is requested, [sqlite3_snprintf()] is used internally to perform the
5191
** conversion automatically.  ^(The following table details the conversions
5192
** that are applied:
5193
**
5194
** <blockquote>
5195
** <table border="1">
5196
** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
5197
**
5198
** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
5199
** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
5200
** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
5201
** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
5202
** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
5203
** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
5204
** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
5205
** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
5206
** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
5207
** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
5208
** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
5209
** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
5210
** <tr><td>  TEXT    <td>   BLOB    <td> No change
5211
** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
5212
** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
5213
** <tr><td>  BLOB    <td>   TEXT    <td> [CAST] to TEXT, ensure zero terminator
5214
** </table>
5215
** </blockquote>)^
5216
**
5217
** Note that when type conversions occur, pointers returned by prior
5218
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
5219
** sqlite3_column_text16() may be invalidated.
5220
** Type conversions and pointer invalidations might occur
5221
** in the following cases:
5222
**
5223
** <ul>
5224
** <li> The initial content is a BLOB and sqlite3_column_text() or
5225
**      sqlite3_column_text16() is called.  A zero-terminator might
5226
**      need to be added to the string.</li>
5227
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
5228
**      sqlite3_column_text16() is called.  The content must be converted
5229
**      to UTF-16.</li>
5230
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
5231
**      sqlite3_column_text() is called.  The content must be converted
5232
**      to UTF-8.</li>
5233
** </ul>
5234
**
5235
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
5236
** not invalidate a prior pointer, though of course the content of the buffer
5237
** that the prior pointer references will have been modified.  Other kinds
5238
** of conversion are done in place when it is possible, but sometimes they
5239
** are not possible and in those cases prior pointers are invalidated.
5240
**
5241
** The safest policy is to invoke these routines
5242
** in one of the following ways:
5243
**
5244
** <ul>
5245
**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
5246
**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
5247
**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
5248
** </ul>
5249
**
5250
** In other words, you should call sqlite3_column_text(),
5251
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
5252
** into the desired format, then invoke sqlite3_column_bytes() or
5253
** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
5254
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
5255
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
5256
** with calls to sqlite3_column_bytes().
5257
**
5258
** ^The pointers returned are valid until a type conversion occurs as
5259
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
5260
** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
5261
** and BLOBs is freed automatically.  Do not pass the pointers returned
5262
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
5263
** [sqlite3_free()].
5264
**
5265
** As long as the input parameters are correct, these routines will only
5266
** fail if an out-of-memory error occurs during a format conversion.
5267
** Only the following subset of interfaces are subject to out-of-memory
5268
** errors:
5269
**
5270
** <ul>
5271
** <li> sqlite3_column_blob()
5272
** <li> sqlite3_column_text()
5273
** <li> sqlite3_column_text16()
5274
** <li> sqlite3_column_bytes()
5275
** <li> sqlite3_column_bytes16()
5276
** </ul>
5277
**
5278
** If an out-of-memory error occurs, then the return value from these
5279
** routines is the same as if the column had contained an SQL NULL value.
5280
** Valid SQL NULL returns can be distinguished from out-of-memory errors
5281
** by invoking the [sqlite3_errcode()] immediately after the suspect
5282
** return value is obtained and before any
5283
** other SQLite interface is called on the same [database connection].
5284
*/
5285
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
5286
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
5287
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
5288
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
5289
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
5290
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
5291
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
5292
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
5293
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
5294
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
5295
5296
/*
5297
** CAPI3REF: Destroy A Prepared Statement Object
5298
** DESTRUCTOR: sqlite3_stmt
5299
**
5300
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
5301
** ^If the most recent evaluation of the statement encountered no errors
5302
** or if the statement is never been evaluated, then sqlite3_finalize() returns
5303
** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
5304
** sqlite3_finalize(S) returns the appropriate [error code] or
5305
** [extended error code].
5306
**
5307
** ^The sqlite3_finalize(S) routine can be called at any point during
5308
** the life cycle of [prepared statement] S:
5309
** before statement S is ever evaluated, after
5310
** one or more calls to [sqlite3_reset()], or after any call
5311
** to [sqlite3_step()] regardless of whether or not the statement has
5312
** completed execution.
5313
**
5314
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
5315
**
5316
** The application must finalize every [prepared statement] in order to avoid
5317
** resource leaks.  It is a grievous error for the application to try to use
5318
** a prepared statement after it has been finalized.  Any use of a prepared
5319
** statement after it has been finalized can result in undefined and
5320
** undesirable behavior such as segfaults and heap corruption.
5321
*/
5322
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
5323
5324
/*
5325
** CAPI3REF: Reset A Prepared Statement Object
5326
** METHOD: sqlite3_stmt
5327
**
5328
** The sqlite3_reset() function is called to reset a [prepared statement]
5329
** object back to its initial state, ready to be re-executed.
5330
** ^Any SQL statement variables that had values bound to them using
5331
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
5332
** Use [sqlite3_clear_bindings()] to reset the bindings.
5333
**
5334
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
5335
** back to the beginning of its program.
5336
**
5337
** ^The return code from [sqlite3_reset(S)] indicates whether or not
5338
** the previous evaluation of prepared statement S completed successfully.
5339
** ^If [sqlite3_step(S)] has never before been called on S or if
5340
** [sqlite3_step(S)] has not been called since the previous call
5341
** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return
5342
** [SQLITE_OK].
5343
**
5344
** ^If the most recent call to [sqlite3_step(S)] for the
5345
** [prepared statement] S indicated an error, then
5346
** [sqlite3_reset(S)] returns an appropriate [error code].
5347
** ^The [sqlite3_reset(S)] interface might also return an [error code]
5348
** if there were no prior errors but the process of resetting
5349
** the prepared statement caused a new error. ^For example, if an
5350
** [INSERT] statement with a [RETURNING] clause is only stepped one time,
5351
** that one call to [sqlite3_step(S)] might return SQLITE_ROW but
5352
** the overall statement might still fail and the [sqlite3_reset(S)] call
5353
** might return SQLITE_BUSY if locking constraints prevent the
5354
** database change from committing.  Therefore, it is important that
5355
** applications check the return code from [sqlite3_reset(S)] even if
5356
** no prior call to [sqlite3_step(S)] indicated a problem.
5357
**
5358
** ^The [sqlite3_reset(S)] interface does not change the values
5359
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
5360
*/
5361
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
5362
5363
5364
/*
5365
** CAPI3REF: Create Or Redefine SQL Functions
5366
** KEYWORDS: {function creation routines}
5367
** METHOD: sqlite3
5368
**
5369
** ^These functions (collectively known as "function creation routines")
5370
** are used to add SQL functions or aggregates or to redefine the behavior
5371
** of existing SQL functions or aggregates. The only differences between
5372
** the three "sqlite3_create_function*" routines are the text encoding
5373
** expected for the second parameter (the name of the function being
5374
** created) and the presence or absence of a destructor callback for
5375
** the application data pointer. Function sqlite3_create_window_function()
5376
** is similar, but allows the user to supply the extra callback functions
5377
** needed by [aggregate window functions].
5378
**
5379
** ^The first parameter is the [database connection] to which the SQL
5380
** function is to be added.  ^If an application uses more than one database
5381
** connection then application-defined SQL functions must be added
5382
** to each database connection separately.
5383
**
5384
** ^The second parameter is the name of the SQL function to be created or
5385
** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
5386
** representation, exclusive of the zero-terminator.  ^Note that the name
5387
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
5388
** ^Any attempt to create a function with a longer name
5389
** will result in [SQLITE_MISUSE] being returned.
5390
**
5391
** ^The third parameter (nArg)
5392
** is the number of arguments that the SQL function or
5393
** aggregate takes. ^If this parameter is -1, then the SQL function or
5394
** aggregate may take any number of arguments between 0 and the limit
5395
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
5396
** parameter is less than -1 or greater than 127 then the behavior is
5397
** undefined.
5398
**
5399
** ^The fourth parameter, eTextRep, specifies what
5400
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
5401
** its parameters.  The application should set this parameter to
5402
** [SQLITE_UTF16LE] if the function implementation invokes
5403
** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
5404
** implementation invokes [sqlite3_value_text16be()] on an input, or
5405
** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
5406
** otherwise.  ^The same SQL function may be registered multiple times using
5407
** different preferred text encodings, with different implementations for
5408
** each encoding.
5409
** ^When multiple implementations of the same function are available, SQLite
5410
** will pick the one that involves the least amount of data conversion.
5411
**
5412
** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
5413
** to signal that the function will always return the same result given
5414
** the same inputs within a single SQL statement.  Most SQL functions are
5415
** deterministic.  The built-in [random()] SQL function is an example of a
5416
** function that is not deterministic.  The SQLite query planner is able to
5417
** perform additional optimizations on deterministic functions, so use
5418
** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
5419
**
5420
** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY]
5421
** flag, which if present prevents the function from being invoked from
5422
** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions,
5423
** index expressions, or the WHERE clause of partial indexes.
5424
**
5425
** For best security, the [SQLITE_DIRECTONLY] flag is recommended for
5426
** all application-defined SQL functions that do not need to be
5427
** used inside of triggers, view, CHECK constraints, or other elements of
5428
** the database schema.  This flags is especially recommended for SQL
5429
** functions that have side effects or reveal internal application state.
5430
** Without this flag, an attacker might be able to modify the schema of
5431
** a database file to include invocations of the function with parameters
5432
** chosen by the attacker, which the application will then execute when
5433
** the database file is opened and read.
5434
**
5435
** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
5436
** function can gain access to this pointer using [sqlite3_user_data()].)^
5437
**
5438
** ^The sixth, seventh and eighth parameters passed to the three
5439
** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are
5440
** pointers to C-language functions that implement the SQL function or
5441
** aggregate. ^A scalar SQL function requires an implementation of the xFunc
5442
** callback only; NULL pointers must be passed as the xStep and xFinal
5443
** parameters. ^An aggregate SQL function requires an implementation of xStep
5444
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
5445
** SQL function or aggregate, pass NULL pointers for all three function
5446
** callbacks.
5447
**
5448
** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue
5449
** and xInverse) passed to sqlite3_create_window_function are pointers to
5450
** C-language callbacks that implement the new function. xStep and xFinal
5451
** must both be non-NULL. xValue and xInverse may either both be NULL, in
5452
** which case a regular aggregate function is created, or must both be
5453
** non-NULL, in which case the new function may be used as either an aggregate
5454
** or aggregate window function. More details regarding the implementation
5455
** of aggregate window functions are
5456
** [user-defined window functions|available here].
5457
**
5458
** ^(If the final parameter to sqlite3_create_function_v2() or
5459
** sqlite3_create_window_function() is not NULL, then it is destructor for
5460
** the application data pointer. The destructor is invoked when the function
5461
** is deleted, either by being overloaded or when the database connection
5462
** closes.)^ ^The destructor is also invoked if the call to
5463
** sqlite3_create_function_v2() fails.  ^When the destructor callback is
5464
** invoked, it is passed a single argument which is a copy of the application
5465
** data pointer which was the fifth parameter to sqlite3_create_function_v2().
5466
**
5467
** ^It is permitted to register multiple implementations of the same
5468
** functions with the same name but with either differing numbers of
5469
** arguments or differing preferred text encodings.  ^SQLite will use
5470
** the implementation that most closely matches the way in which the
5471
** SQL function is used.  ^A function implementation with a non-negative
5472
** nArg parameter is a better match than a function implementation with
5473
** a negative nArg.  ^A function where the preferred text encoding
5474
** matches the database encoding is a better
5475
** match than a function where the encoding is different.
5476
** ^A function where the encoding difference is between UTF16le and UTF16be
5477
** is a closer match than a function where the encoding difference is
5478
** between UTF8 and UTF16.
5479
**
5480
** ^Built-in functions may be overloaded by new application-defined functions.
5481
**
5482
** ^An application-defined function is permitted to call other
5483
** SQLite interfaces.  However, such calls must not
5484
** close the database connection nor finalize or reset the prepared
5485
** statement in which the function is running.
5486
*/
5487
SQLITE_API int sqlite3_create_function(
5488
  sqlite3 *db,
5489
  const char *zFunctionName,
5490
  int nArg,
5491
  int eTextRep,
5492
  void *pApp,
5493
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5494
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5495
  void (*xFinal)(sqlite3_context*)
5496
);
5497
SQLITE_API int sqlite3_create_function16(
5498
  sqlite3 *db,
5499
  const void *zFunctionName,
5500
  int nArg,
5501
  int eTextRep,
5502
  void *pApp,
5503
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5504
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5505
  void (*xFinal)(sqlite3_context*)
5506
);
5507
SQLITE_API int sqlite3_create_function_v2(
5508
  sqlite3 *db,
5509
  const char *zFunctionName,
5510
  int nArg,
5511
  int eTextRep,
5512
  void *pApp,
5513
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
5514
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5515
  void (*xFinal)(sqlite3_context*),
5516
  void(*xDestroy)(void*)
5517
);
5518
SQLITE_API int sqlite3_create_window_function(
5519
  sqlite3 *db,
5520
  const char *zFunctionName,
5521
  int nArg,
5522
  int eTextRep,
5523
  void *pApp,
5524
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
5525
  void (*xFinal)(sqlite3_context*),
5526
  void (*xValue)(sqlite3_context*),
5527
  void (*xInverse)(sqlite3_context*,int,sqlite3_value**),
5528
  void(*xDestroy)(void*)
5529
);
5530
5531
/*
5532
** CAPI3REF: Text Encodings
5533
**
5534
** These constant define integer codes that represent the various
5535
** text encodings supported by SQLite.
5536
*/
5537
#define SQLITE_UTF8           1    /* IMP: R-37514-35566 */
5538
#define SQLITE_UTF16LE        2    /* IMP: R-03371-37637 */
5539
#define SQLITE_UTF16BE        3    /* IMP: R-51971-34154 */
5540
#define SQLITE_UTF16          4    /* Use native byte order */
5541
#define SQLITE_ANY            5    /* Deprecated */
5542
#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
5543
5544
/*
5545
** CAPI3REF: Function Flags
5546
**
5547
** These constants may be ORed together with the
5548
** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
5549
** to [sqlite3_create_function()], [sqlite3_create_function16()], or
5550
** [sqlite3_create_function_v2()].
5551
**
5552
** <dl>
5553
** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd>
5554
** The SQLITE_DETERMINISTIC flag means that the new function always gives
5555
** the same output when the input parameters are the same.
5556
** The [abs|abs() function] is deterministic, for example, but
5557
** [randomblob|randomblob()] is not.  Functions must
5558
** be deterministic in order to be used in certain contexts such as
5559
** with the WHERE clause of [partial indexes] or in [generated columns].
5560
** SQLite might also optimize deterministic functions by factoring them
5561
** out of inner loops.
5562
** </dd>
5563
**
5564
** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd>
5565
** The SQLITE_DIRECTONLY flag means that the function may only be invoked
5566
** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in
5567
** schema structures such as [CHECK constraints], [DEFAULT clauses],
5568
** [expression indexes], [partial indexes], or [generated columns].
5569
** <p>
5570
** The SQLITE_DIRECTONLY flag is recommended for any
5571
** [application-defined SQL function]
5572
** that has side-effects or that could potentially leak sensitive information.
5573
** This will prevent attacks in which an application is tricked
5574
** into using a database file that has had its schema surreptitiously
5575
** modified to invoke the application-defined function in ways that are
5576
** harmful.
5577
** <p>
5578
** Some people say it is good practice to set SQLITE_DIRECTONLY on all
5579
** [application-defined SQL functions], regardless of whether or not they
5580
** are security sensitive, as doing so prevents those functions from being used
5581
** inside of the database schema, and thus ensures that the database
5582
** can be inspected and modified using generic tools (such as the [CLI])
5583
** that do not have access to the application-defined functions.
5584
** </dd>
5585
**
5586
** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd>
5587
** The SQLITE_INNOCUOUS flag means that the function is unlikely
5588
** to cause problems even if misused.  An innocuous function should have
5589
** no side effects and should not depend on any values other than its
5590
** input parameters. The [abs|abs() function] is an example of an
5591
** innocuous function.
5592
** The [load_extension() SQL function] is not innocuous because of its
5593
** side effects.
5594
** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not
5595
** exactly the same.  The [random|random() function] is an example of a
5596
** function that is innocuous but not deterministic.
5597
** <p>Some heightened security settings
5598
** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF])
5599
** disable the use of SQL functions inside views and triggers and in
5600
** schema structures such as [CHECK constraints], [DEFAULT clauses],
5601
** [expression indexes], [partial indexes], and [generated columns] unless
5602
** the function is tagged with SQLITE_INNOCUOUS.  Most built-in functions
5603
** are innocuous.  Developers are advised to avoid using the
5604
** SQLITE_INNOCUOUS flag for application-defined functions unless the
5605
** function has been carefully audited and found to be free of potentially
5606
** security-adverse side-effects and information-leaks.
5607
** </dd>
5608
**
5609
** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
5610
** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call
5611
** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
5612
** This flag instructs SQLite to omit some corner-case optimizations that
5613
** might disrupt the operation of the [sqlite3_value_subtype()] function,
5614
** causing it to return zero rather than the correct subtype().
5615
** All SQL functions that invoke [sqlite3_value_subtype()] should have this
5616
** property.  If the SQLITE_SUBTYPE property is omitted, then the return
5617
** value from [sqlite3_value_subtype()] might sometimes be zero even though
5618
** a non-zero subtype was specified by the function argument expression.
5619
**
5620
** [[SQLITE_RESULT_SUBTYPE]] <dt>SQLITE_RESULT_SUBTYPE</dt><dd>
5621
** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call
5622
** [sqlite3_result_subtype()] to cause a sub-type to be associated with its
5623
** result.
5624
** Every function that invokes [sqlite3_result_subtype()] should have this
5625
** property.  If it does not, then the call to [sqlite3_result_subtype()]
5626
** might become a no-op if the function is used as term in an
5627
** [expression index].  On the other hand, SQL functions that never invoke
5628
** [sqlite3_result_subtype()] should avoid setting this property, as the
5629
** purpose of this property is to disable certain optimizations that are
5630
** incompatible with subtypes.
5631
**
5632
** [[SQLITE_SELFORDER1]] <dt>SQLITE_SELFORDER1</dt><dd>
5633
** The SQLITE_SELFORDER1 flag indicates that the function is an aggregate
5634
** that internally orders the values provided to the first argument.  The
5635
** ordered-set aggregate SQL notation with a single ORDER BY term can be
5636
** used to invoke this function.  If the ordered-set aggregate notation is
5637
** used on a function that lacks this flag, then an error is raised. Note
5638
** that the ordered-set aggregate syntax is only available if SQLite is
5639
** built using the -DSQLITE_ENABLE_ORDERED_SET_AGGREGATES compile-time option.
5640
** </dd>
5641
** </dl>
5642
*/
5643
#define SQLITE_DETERMINISTIC    0x000000800
5644
#define SQLITE_DIRECTONLY       0x000080000
5645
#define SQLITE_SUBTYPE          0x000100000
5646
#define SQLITE_INNOCUOUS        0x000200000
5647
#define SQLITE_RESULT_SUBTYPE   0x001000000
5648
#define SQLITE_SELFORDER1       0x002000000
5649
5650
/*
5651
** CAPI3REF: Deprecated Functions
5652
** DEPRECATED
5653
**
5654
** These functions are [deprecated].  In order to maintain
5655
** backwards compatibility with older code, these functions continue
5656
** to be supported.  However, new applications should avoid
5657
** the use of these functions.  To encourage programmers to avoid
5658
** these functions, we will not explain what they do.
5659
*/
5660
#ifndef SQLITE_OMIT_DEPRECATED
5661
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
5662
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
5663
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
5664
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
5665
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
5666
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
5667
                      void*,sqlite3_int64);
5668
#endif
5669
5670
/*
5671
** CAPI3REF: Obtaining SQL Values
5672
** METHOD: sqlite3_value
5673
**
5674
** <b>Summary:</b>
5675
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
5676
** <tr><td><b>sqlite3_value_blob</b><td>&rarr;<td>BLOB value
5677
** <tr><td><b>sqlite3_value_double</b><td>&rarr;<td>REAL value
5678
** <tr><td><b>sqlite3_value_int</b><td>&rarr;<td>32-bit INTEGER value
5679
** <tr><td><b>sqlite3_value_int64</b><td>&rarr;<td>64-bit INTEGER value
5680
** <tr><td><b>sqlite3_value_pointer</b><td>&rarr;<td>Pointer value
5681
** <tr><td><b>sqlite3_value_text</b><td>&rarr;<td>UTF-8 TEXT value
5682
** <tr><td><b>sqlite3_value_text16</b><td>&rarr;<td>UTF-16 TEXT value in
5683
** the native byteorder
5684
** <tr><td><b>sqlite3_value_text16be</b><td>&rarr;<td>UTF-16be TEXT value
5685
** <tr><td><b>sqlite3_value_text16le</b><td>&rarr;<td>UTF-16le TEXT value
5686
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
5687
** <tr><td><b>sqlite3_value_bytes</b><td>&rarr;<td>Size of a BLOB
5688
** or a UTF-8 TEXT in bytes
5689
** <tr><td><b>sqlite3_value_bytes16&nbsp;&nbsp;</b>
5690
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
5691
** TEXT in bytes
5692
** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
5693
** datatype of the value
5694
** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
5695
** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
5696
** <tr><td><b>sqlite3_value_nochange&nbsp;&nbsp;</b>
5697
** <td>&rarr;&nbsp;&nbsp;<td>True if the column is unchanged in an UPDATE
5698
** against a virtual table.
5699
** <tr><td><b>sqlite3_value_frombind&nbsp;&nbsp;</b>
5700
** <td>&rarr;&nbsp;&nbsp;<td>True if value originated from a [bound parameter]
5701
** </table></blockquote>
5702
**
5703
** <b>Details:</b>
5704
**
5705
** These routines extract type, size, and content information from
5706
** [protected sqlite3_value] objects.  Protected sqlite3_value objects
5707
** are used to pass parameter information into the functions that
5708
** implement [application-defined SQL functions] and [virtual tables].
5709
**
5710
** These routines work only with [protected sqlite3_value] objects.
5711
** Any attempt to use these routines on an [unprotected sqlite3_value]
5712
** is not threadsafe.
5713
**
5714
** ^These routines work just like the corresponding [column access functions]
5715
** except that these routines take a single [protected sqlite3_value] object
5716
** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
5717
**
5718
** ^The sqlite3_value_text16() interface extracts a UTF-16 string
5719
** in the native byte-order of the host machine.  ^The
5720
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
5721
** extract UTF-16 strings as big-endian and little-endian respectively.
5722
**
5723
** ^If [sqlite3_value] object V was initialized
5724
** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
5725
** and if X and Y are strings that compare equal according to strcmp(X,Y),
5726
** then sqlite3_value_pointer(V,Y) will return the pointer P.  ^Otherwise,
5727
** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
5728
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5729
**
5730
** ^(The sqlite3_value_type(V) interface returns the
5731
** [SQLITE_INTEGER | datatype code] for the initial datatype of the
5732
** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
5733
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
5734
** Other interfaces might change the datatype for an sqlite3_value object.
5735
** For example, if the datatype is initially SQLITE_INTEGER and
5736
** sqlite3_value_text(V) is called to extract a text value for that
5737
** integer, then subsequent calls to sqlite3_value_type(V) might return
5738
** SQLITE_TEXT.  Whether or not a persistent internal datatype conversion
5739
** occurs is undefined and may change from one release of SQLite to the next.
5740
**
5741
** ^(The sqlite3_value_numeric_type() interface attempts to apply
5742
** numeric affinity to the value.  This means that an attempt is
5743
** made to convert the value to an integer or floating point.  If
5744
** such a conversion is possible without loss of information (in other
5745
** words, if the value is a string that looks like a number)
5746
** then the conversion is performed.  Otherwise no conversion occurs.
5747
** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
5748
**
5749
** ^Within the [xUpdate] method of a [virtual table], the
5750
** sqlite3_value_nochange(X) interface returns true if and only if
5751
** the column corresponding to X is unchanged by the UPDATE operation
5752
** that the xUpdate method call was invoked to implement and if
5753
** and the prior [xColumn] method call that was invoked to extracted
5754
** the value for that column returned without setting a result (probably
5755
** because it queried [sqlite3_vtab_nochange()] and found that the column
5756
** was unchanging).  ^Within an [xUpdate] method, any value for which
5757
** sqlite3_value_nochange(X) is true will in all other respects appear
5758
** to be a NULL value.  If sqlite3_value_nochange(X) is invoked anywhere other
5759
** than within an [xUpdate] method call for an UPDATE statement, then
5760
** the return value is arbitrary and meaningless.
5761
**
5762
** ^The sqlite3_value_frombind(X) interface returns non-zero if the
5763
** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()]
5764
** interfaces.  ^If X comes from an SQL literal value, or a table column,
5765
** or an expression, then sqlite3_value_frombind(X) returns zero.
5766
**
5767
** Please pay particular attention to the fact that the pointer returned
5768
** from [sqlite3_value_blob()], [sqlite3_value_text()], or
5769
** [sqlite3_value_text16()] can be invalidated by a subsequent call to
5770
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
5771
** or [sqlite3_value_text16()].
5772
**
5773
** These routines must be called from the same thread as
5774
** the SQL function that supplied the [sqlite3_value*] parameters.
5775
**
5776
** As long as the input parameter is correct, these routines can only
5777
** fail if an out-of-memory error occurs during a format conversion.
5778
** Only the following subset of interfaces are subject to out-of-memory
5779
** errors:
5780
**
5781
** <ul>
5782
** <li> sqlite3_value_blob()
5783
** <li> sqlite3_value_text()
5784
** <li> sqlite3_value_text16()
5785
** <li> sqlite3_value_text16le()
5786
** <li> sqlite3_value_text16be()
5787
** <li> sqlite3_value_bytes()
5788
** <li> sqlite3_value_bytes16()
5789
** </ul>
5790
**
5791
** If an out-of-memory error occurs, then the return value from these
5792
** routines is the same as if the column had contained an SQL NULL value.
5793
** Valid SQL NULL returns can be distinguished from out-of-memory errors
5794
** by invoking the [sqlite3_errcode()] immediately after the suspect
5795
** return value is obtained and before any
5796
** other SQLite interface is called on the same [database connection].
5797
*/
5798
SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
5799
SQLITE_API double sqlite3_value_double(sqlite3_value*);
5800
SQLITE_API int sqlite3_value_int(sqlite3_value*);
5801
SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
5802
SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
5803
SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
5804
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
5805
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
5806
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
5807
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
5808
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
5809
SQLITE_API int sqlite3_value_type(sqlite3_value*);
5810
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
5811
SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
5812
SQLITE_API int sqlite3_value_frombind(sqlite3_value*);
5813
5814
/*
5815
** CAPI3REF: Report the internal text encoding state of an sqlite3_value object
5816
** METHOD: sqlite3_value
5817
**
5818
** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8],
5819
** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding
5820
** of the value X, assuming that X has type TEXT.)^  If sqlite3_value_type(X)
5821
** returns something other than SQLITE_TEXT, then the return value from
5822
** sqlite3_value_encoding(X) is meaningless.  ^Calls to
5823
** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], [sqlite3_value_text16be(X)],
5824
** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or
5825
** [sqlite3_value_bytes16(X)] might change the encoding of the value X and
5826
** thus change the return from subsequent calls to sqlite3_value_encoding(X).
5827
**
5828
** This routine is intended for used by applications that test and validate
5829
** the SQLite implementation.  This routine is inquiring about the opaque
5830
** internal state of an [sqlite3_value] object.  Ordinary applications should
5831
** not need to know what the internal state of an sqlite3_value object is and
5832
** hence should not need to use this interface.
5833
*/
5834
SQLITE_API int sqlite3_value_encoding(sqlite3_value*);
5835
5836
/*
5837
** CAPI3REF: Finding The Subtype Of SQL Values
5838
** METHOD: sqlite3_value
5839
**
5840
** The sqlite3_value_subtype(V) function returns the subtype for
5841
** an [application-defined SQL function] argument V.  The subtype
5842
** information can be used to pass a limited amount of context from
5843
** one SQL function to another.  Use the [sqlite3_result_subtype()]
5844
** routine to set the subtype for the return value of an SQL function.
5845
**
5846
** Every [application-defined SQL function] that invokes this interface
5847
** should include the [SQLITE_SUBTYPE] property in the text
5848
** encoding argument when the function is [sqlite3_create_function|registered].
5849
** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype()
5850
** might return zero instead of the upstream subtype in some corner cases.
5851
*/
5852
SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
5853
5854
/*
5855
** CAPI3REF: Copy And Free SQL Values
5856
** METHOD: sqlite3_value
5857
**
5858
** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
5859
** object D and returns a pointer to that copy.  ^The [sqlite3_value] returned
5860
** is a [protected sqlite3_value] object even if the input is not.
5861
** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
5862
** memory allocation fails. ^If V is a [pointer value], then the result
5863
** of sqlite3_value_dup(V) is a NULL value.
5864
**
5865
** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
5866
** previously obtained from [sqlite3_value_dup()].  ^If V is a NULL pointer
5867
** then sqlite3_value_free(V) is a harmless no-op.
5868
*/
5869
SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
5870
SQLITE_API void sqlite3_value_free(sqlite3_value*);
5871
5872
/*
5873
** CAPI3REF: Obtain Aggregate Function Context
5874
** METHOD: sqlite3_context
5875
**
5876
** Implementations of aggregate SQL functions use this
5877
** routine to allocate memory for storing their state.
5878
**
5879
** ^The first time the sqlite3_aggregate_context(C,N) routine is called
5880
** for a particular aggregate function, SQLite allocates
5881
** N bytes of memory, zeroes out that memory, and returns a pointer
5882
** to the new memory. ^On second and subsequent calls to
5883
** sqlite3_aggregate_context() for the same aggregate function instance,
5884
** the same buffer is returned.  Sqlite3_aggregate_context() is normally
5885
** called once for each invocation of the xStep callback and then one
5886
** last time when the xFinal callback is invoked.  ^(When no rows match
5887
** an aggregate query, the xStep() callback of the aggregate function
5888
** implementation is never called and xFinal() is called exactly once.
5889
** In those cases, sqlite3_aggregate_context() might be called for the
5890
** first time from within xFinal().)^
5891
**
5892
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
5893
** when first called if N is less than or equal to zero or if a memory
5894
** allocation error occurs.
5895
**
5896
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
5897
** determined by the N parameter on first successful call.  Changing the
5898
** value of N in any subsequent call to sqlite3_aggregate_context() within
5899
** the same aggregate function instance will not resize the memory
5900
** allocation.)^  Within the xFinal callback, it is customary to set
5901
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
5902
** pointless memory allocations occur.
5903
**
5904
** ^SQLite automatically frees the memory allocated by
5905
** sqlite3_aggregate_context() when the aggregate query concludes.
5906
**
5907
** The first parameter must be a copy of the
5908
** [sqlite3_context | SQL function context] that is the first parameter
5909
** to the xStep or xFinal callback routine that implements the aggregate
5910
** function.
5911
**
5912
** This routine must be called from the same thread in which
5913
** the aggregate SQL function is running.
5914
*/
5915
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
5916
5917
/*
5918
** CAPI3REF: User Data For Functions
5919
** METHOD: sqlite3_context
5920
**
5921
** ^The sqlite3_user_data() interface returns a copy of
5922
** the pointer that was the pUserData parameter (the 5th parameter)
5923
** of the [sqlite3_create_function()]
5924
** and [sqlite3_create_function16()] routines that originally
5925
** registered the application defined function.
5926
**
5927
** This routine must be called from the same thread in which
5928
** the application-defined function is running.
5929
*/
5930
SQLITE_API void *sqlite3_user_data(sqlite3_context*);
5931
5932
/*
5933
** CAPI3REF: Database Connection For Functions
5934
** METHOD: sqlite3_context
5935
**
5936
** ^The sqlite3_context_db_handle() interface returns a copy of
5937
** the pointer to the [database connection] (the 1st parameter)
5938
** of the [sqlite3_create_function()]
5939
** and [sqlite3_create_function16()] routines that originally
5940
** registered the application defined function.
5941
*/
5942
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
5943
5944
/*
5945
** CAPI3REF: Function Auxiliary Data
5946
** METHOD: sqlite3_context
5947
**
5948
** These functions may be used by (non-aggregate) SQL functions to
5949
** associate auxiliary data with argument values. If the same argument
5950
** value is passed to multiple invocations of the same SQL function during
5951
** query execution, under some circumstances the associated auxiliary data
5952
** might be preserved.  An example of where this might be useful is in a
5953
** regular-expression matching function. The compiled version of the regular
5954
** expression can be stored as auxiliary data associated with the pattern string.
5955
** Then as long as the pattern string remains the same,
5956
** the compiled regular expression can be reused on multiple
5957
** invocations of the same function.
5958
**
5959
** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the auxiliary data
5960
** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
5961
** value to the application-defined function.  ^N is zero for the left-most
5962
** function argument.  ^If there is no auxiliary data
5963
** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
5964
** returns a NULL pointer.
5965
**
5966
** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as auxiliary data for the
5967
** N-th argument of the application-defined function.  ^Subsequent
5968
** calls to sqlite3_get_auxdata(C,N) return P from the most recent
5969
** sqlite3_set_auxdata(C,N,P,X) call if the auxiliary data is still valid or
5970
** NULL if the auxiliary data has been discarded.
5971
** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
5972
** SQLite will invoke the destructor function X with parameter P exactly
5973
** once, when the auxiliary data is discarded.
5974
** SQLite is free to discard the auxiliary data at any time, including: <ul>
5975
** <li> ^(when the corresponding function parameter changes)^, or
5976
** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
5977
**      SQL statement)^, or
5978
** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
5979
**       parameter)^, or
5980
** <li> ^(during the original sqlite3_set_auxdata() call when a memory
5981
**      allocation error occurs.)^
5982
** <li> ^(during the original sqlite3_set_auxdata() call if the function
5983
**      is evaluated during query planning instead of during query execution,
5984
**      as sometimes happens with [SQLITE_ENABLE_STAT4].)^ </ul>
5985
**
5986
** Note the last two bullets in particular.  The destructor X in
5987
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
5988
** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
5989
** should be called near the end of the function implementation and the
5990
** function implementation should not make any use of P after
5991
** sqlite3_set_auxdata() has been called.  Furthermore, a call to
5992
** sqlite3_get_auxdata() that occurs immediately after a corresponding call
5993
** to sqlite3_set_auxdata() might still return NULL if an out-of-memory
5994
** condition occurred during the sqlite3_set_auxdata() call or if the
5995
** function is being evaluated during query planning rather than during
5996
** query execution.
5997
**
5998
** ^(In practice, auxiliary data is preserved between function calls for
5999
** function parameters that are compile-time constants, including literal
6000
** values and [parameters] and expressions composed from the same.)^
6001
**
6002
** The value of the N parameter to these interfaces should be non-negative.
6003
** Future enhancements may make use of negative N values to define new
6004
** kinds of function caching behavior.
6005
**
6006
** These routines must be called from the same thread in which
6007
** the SQL function is running.
6008
**
6009
** See also: [sqlite3_get_clientdata()] and [sqlite3_set_clientdata()].
6010
*/
6011
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
6012
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
6013
6014
/*
6015
** CAPI3REF: Database Connection Client Data
6016
** METHOD: sqlite3
6017
**
6018
** These functions are used to associate one or more named pointers
6019
** with a [database connection].
6020
** A call to sqlite3_set_clientdata(D,N,P,X) causes the pointer P
6021
** to be attached to [database connection] D using name N.  Subsequent
6022
** calls to sqlite3_get_clientdata(D,N) will return a copy of pointer P
6023
** or a NULL pointer if there were no prior calls to
6024
** sqlite3_set_clientdata() with the same values of D and N.
6025
** Names are compared using strcmp() and are thus case sensitive.
6026
**
6027
** If P and X are both non-NULL, then the destructor X is invoked with
6028
** argument P on the first of the following occurrences:
6029
** <ul>
6030
** <li> An out-of-memory error occurs during the call to
6031
**      sqlite3_set_clientdata() which attempts to register pointer P.
6032
** <li> A subsequent call to sqlite3_set_clientdata(D,N,P,X) is made
6033
**      with the same D and N parameters.
6034
** <li> The database connection closes.  SQLite does not make any guarantees
6035
**      about the order in which destructors are called, only that all
6036
**      destructors will be called exactly once at some point during the
6037
**      database connection closing process.
6038
** </ul>
6039
**
6040
** SQLite does not do anything with client data other than invoke
6041
** destructors on the client data at the appropriate time.  The intended
6042
** use for client data is to provide a mechanism for wrapper libraries
6043
** to store additional information about an SQLite database connection.
6044
**
6045
** There is no limit (other than available memory) on the number of different
6046
** client data pointers (with different names) that can be attached to a
6047
** single database connection.  However, the implementation is optimized
6048
** for the case of having only one or two different client data names.
6049
** Applications and wrapper libraries are discouraged from using more than
6050
** one client data name each.
6051
**
6052
** There is no way to enumerate the client data pointers
6053
** associated with a database connection.  The N parameter can be thought
6054
** of as a secret key such that only code that knows the secret key is able
6055
** to access the associated data.
6056
**
6057
** Security Warning:  These interfaces should not be exposed in scripting
6058
** languages or in other circumstances where it might be possible for an
6059
** an attacker to invoke them.  Any agent that can invoke these interfaces
6060
** can probably also take control of the process.
6061
**
6062
** Database connection client data is only available for SQLite
6063
** version 3.44.0 ([dateof:3.44.0]) and later.
6064
**
6065
** See also: [sqlite3_set_auxdata()] and [sqlite3_get_auxdata()].
6066
*/
6067
SQLITE_API void *sqlite3_get_clientdata(sqlite3*,const char*);
6068
SQLITE_API int sqlite3_set_clientdata(sqlite3*, const char*, void*, void(*)(void*));
6069
6070
/*
6071
** CAPI3REF: Constants Defining Special Destructor Behavior
6072
**
6073
** These are special values for the destructor that is passed in as the
6074
** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
6075
** argument is SQLITE_STATIC, it means that the content pointer is constant
6076
** and will never change.  It does not need to be destroyed.  ^The
6077
** SQLITE_TRANSIENT value means that the content will likely change in
6078
** the near future and that SQLite should make its own private copy of
6079
** the content before returning.
6080
**
6081
** The typedef is necessary to work around problems in certain
6082
** C++ compilers.
6083
*/
6084
typedef void (*sqlite3_destructor_type)(void*);
6085
0
#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
6086
#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
6087
6088
/*
6089
** CAPI3REF: Setting The Result Of An SQL Function
6090
** METHOD: sqlite3_context
6091
**
6092
** These routines are used by the xFunc or xFinal callbacks that
6093
** implement SQL functions and aggregates.  See
6094
** [sqlite3_create_function()] and [sqlite3_create_function16()]
6095
** for additional information.
6096
**
6097
** These functions work very much like the [parameter binding] family of
6098
** functions used to bind values to host parameters in prepared statements.
6099
** Refer to the [SQL parameter] documentation for additional information.
6100
**
6101
** ^The sqlite3_result_blob() interface sets the result from
6102
** an application-defined function to be the BLOB whose content is pointed
6103
** to by the second parameter and which is N bytes long where N is the
6104
** third parameter.
6105
**
6106
** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
6107
** interfaces set the result of the application-defined function to be
6108
** a BLOB containing all zero bytes and N bytes in size.
6109
**
6110
** ^The sqlite3_result_double() interface sets the result from
6111
** an application-defined function to be a floating point value specified
6112
** by its 2nd argument.
6113
**
6114
** ^The sqlite3_result_error() and sqlite3_result_error16() functions
6115
** cause the implemented SQL function to throw an exception.
6116
** ^SQLite uses the string pointed to by the
6117
** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
6118
** as the text of an error message.  ^SQLite interprets the error
6119
** message string from sqlite3_result_error() as UTF-8. ^SQLite
6120
** interprets the string from sqlite3_result_error16() as UTF-16 using
6121
** the same [byte-order determination rules] as [sqlite3_bind_text16()].
6122
** ^If the third parameter to sqlite3_result_error()
6123
** or sqlite3_result_error16() is negative then SQLite takes as the error
6124
** message all text up through the first zero character.
6125
** ^If the third parameter to sqlite3_result_error() or
6126
** sqlite3_result_error16() is non-negative then SQLite takes that many
6127
** bytes (not characters) from the 2nd parameter as the error message.
6128
** ^The sqlite3_result_error() and sqlite3_result_error16()
6129
** routines make a private copy of the error message text before
6130
** they return.  Hence, the calling function can deallocate or
6131
** modify the text after they return without harm.
6132
** ^The sqlite3_result_error_code() function changes the error code
6133
** returned by SQLite as a result of an error in a function.  ^By default,
6134
** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
6135
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
6136
**
6137
** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
6138
** error indicating that a string or BLOB is too long to represent.
6139
**
6140
** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
6141
** error indicating that a memory allocation failed.
6142
**
6143
** ^The sqlite3_result_int() interface sets the return value
6144
** of the application-defined function to be the 32-bit signed integer
6145
** value given in the 2nd argument.
6146
** ^The sqlite3_result_int64() interface sets the return value
6147
** of the application-defined function to be the 64-bit signed integer
6148
** value given in the 2nd argument.
6149
**
6150
** ^The sqlite3_result_null() interface sets the return value
6151
** of the application-defined function to be NULL.
6152
**
6153
** ^The sqlite3_result_text(), sqlite3_result_text16(),
6154
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
6155
** set the return value of the application-defined function to be
6156
** a text string which is represented as UTF-8, UTF-16 native byte order,
6157
** UTF-16 little endian, or UTF-16 big endian, respectively.
6158
** ^The sqlite3_result_text64() interface sets the return value of an
6159
** application-defined function to be a text string in an encoding
6160
** specified by the fifth (and last) parameter, which must be one
6161
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
6162
** ^SQLite takes the text result from the application from
6163
** the 2nd parameter of the sqlite3_result_text* interfaces.
6164
** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces
6165
** other than sqlite3_result_text64() is negative, then SQLite computes
6166
** the string length itself by searching the 2nd parameter for the first
6167
** zero character.
6168
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
6169
** is non-negative, then as many bytes (not characters) of the text
6170
** pointed to by the 2nd parameter are taken as the application-defined
6171
** function result.  If the 3rd parameter is non-negative, then it
6172
** must be the byte offset into the string where the NUL terminator would
6173
** appear if the string where NUL terminated.  If any NUL characters occur
6174
** in the string at a byte offset that is less than the value of the 3rd
6175
** parameter, then the resulting string will contain embedded NULs and the
6176
** result of expressions operating on strings with embedded NULs is undefined.
6177
** ^If the 4th parameter to the sqlite3_result_text* interfaces
6178
** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
6179
** function as the destructor on the text or BLOB result when it has
6180
** finished using that result.
6181
** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
6182
** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
6183
** assumes that the text or BLOB result is in constant space and does not
6184
** copy the content of the parameter nor call a destructor on the content
6185
** when it has finished using that result.
6186
** ^If the 4th parameter to the sqlite3_result_text* interfaces
6187
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
6188
** then SQLite makes a copy of the result into space obtained
6189
** from [sqlite3_malloc()] before it returns.
6190
**
6191
** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and
6192
** sqlite3_result_text16be() routines, and for sqlite3_result_text64()
6193
** when the encoding is not UTF8, if the input UTF16 begins with a
6194
** byte-order mark (BOM, U+FEFF) then the BOM is removed from the
6195
** string and the rest of the string is interpreted according to the
6196
** byte-order specified by the BOM.  ^The byte-order specified by
6197
** the BOM at the beginning of the text overrides the byte-order
6198
** specified by the interface procedure.  ^So, for example, if
6199
** sqlite3_result_text16le() is invoked with text that begins
6200
** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the
6201
** first two bytes of input are skipped and the remaining input
6202
** is interpreted as UTF16BE text.
6203
**
6204
** ^For UTF16 input text to the sqlite3_result_text16(),
6205
** sqlite3_result_text16be(), sqlite3_result_text16le(), and
6206
** sqlite3_result_text64() routines, if the text contains invalid
6207
** UTF16 characters, the invalid characters might be converted
6208
** into the unicode replacement character, U+FFFD.
6209
**
6210
** ^The sqlite3_result_value() interface sets the result of
6211
** the application-defined function to be a copy of the
6212
** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
6213
** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
6214
** so that the [sqlite3_value] specified in the parameter may change or
6215
** be deallocated after sqlite3_result_value() returns without harm.
6216
** ^A [protected sqlite3_value] object may always be used where an
6217
** [unprotected sqlite3_value] object is required, so either
6218
** kind of [sqlite3_value] object can be used with this interface.
6219
**
6220
** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
6221
** SQL NULL value, just like [sqlite3_result_null(C)], except that it
6222
** also associates the host-language pointer P or type T with that
6223
** NULL value such that the pointer can be retrieved within an
6224
** [application-defined SQL function] using [sqlite3_value_pointer()].
6225
** ^If the D parameter is not NULL, then it is a pointer to a destructor
6226
** for the P parameter.  ^SQLite invokes D with P as its only argument
6227
** when SQLite is finished with P.  The T parameter should be a static
6228
** string and preferably a string literal. The sqlite3_result_pointer()
6229
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
6230
**
6231
** If these routines are called from within the different thread
6232
** than the one containing the application-defined function that received
6233
** the [sqlite3_context] pointer, the results are undefined.
6234
*/
6235
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
6236
SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
6237
                           sqlite3_uint64,void(*)(void*));
6238
SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
6239
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
6240
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
6241
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
6242
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
6243
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
6244
SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
6245
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
6246
SQLITE_API void sqlite3_result_null(sqlite3_context*);
6247
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
6248
SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
6249
                           void(*)(void*), unsigned char encoding);
6250
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
6251
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
6252
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
6253
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
6254
SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
6255
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
6256
SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
6257
6258
6259
/*
6260
** CAPI3REF: Setting The Subtype Of An SQL Function
6261
** METHOD: sqlite3_context
6262
**
6263
** The sqlite3_result_subtype(C,T) function causes the subtype of
6264
** the result from the [application-defined SQL function] with
6265
** [sqlite3_context] C to be the value T.  Only the lower 8 bits
6266
** of the subtype T are preserved in current versions of SQLite;
6267
** higher order bits are discarded.
6268
** The number of subtype bytes preserved by SQLite might increase
6269
** in future releases of SQLite.
6270
**
6271
** Every [application-defined SQL function] that invokes this interface
6272
** should include the [SQLITE_RESULT_SUBTYPE] property in its
6273
** text encoding argument when the SQL function is
6274
** [sqlite3_create_function|registered].  If the [SQLITE_RESULT_SUBTYPE]
6275
** property is omitted from the function that invokes sqlite3_result_subtype(),
6276
** then in some cases the sqlite3_result_subtype() might fail to set
6277
** the result subtype.
6278
**
6279
** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any
6280
** SQL function that invokes the sqlite3_result_subtype() interface
6281
** and that does not have the SQLITE_RESULT_SUBTYPE property will raise
6282
** an error.  Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1
6283
** by default.
6284
*/
6285
SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
6286
6287
/*
6288
** CAPI3REF: Define New Collating Sequences
6289
** METHOD: sqlite3
6290
**
6291
** ^These functions add, remove, or modify a [collation] associated
6292
** with the [database connection] specified as the first argument.
6293
**
6294
** ^The name of the collation is a UTF-8 string
6295
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
6296
** and a UTF-16 string in native byte order for sqlite3_create_collation16().
6297
** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
6298
** considered to be the same name.
6299
**
6300
** ^(The third argument (eTextRep) must be one of the constants:
6301
** <ul>
6302
** <li> [SQLITE_UTF8],
6303
** <li> [SQLITE_UTF16LE],
6304
** <li> [SQLITE_UTF16BE],
6305
** <li> [SQLITE_UTF16], or
6306
** <li> [SQLITE_UTF16_ALIGNED].
6307
** </ul>)^
6308
** ^The eTextRep argument determines the encoding of strings passed
6309
** to the collating function callback, xCompare.
6310
** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
6311
** force strings to be UTF16 with native byte order.
6312
** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
6313
** on an even byte address.
6314
**
6315
** ^The fourth argument, pArg, is an application data pointer that is passed
6316
** through as the first argument to the collating function callback.
6317
**
6318
** ^The fifth argument, xCompare, is a pointer to the collating function.
6319
** ^Multiple collating functions can be registered using the same name but
6320
** with different eTextRep parameters and SQLite will use whichever
6321
** function requires the least amount of data transformation.
6322
** ^If the xCompare argument is NULL then the collating function is
6323
** deleted.  ^When all collating functions having the same name are deleted,
6324
** that collation is no longer usable.
6325
**
6326
** ^The collating function callback is invoked with a copy of the pArg
6327
** application data pointer and with two strings in the encoding specified
6328
** by the eTextRep argument.  The two integer parameters to the collating
6329
** function callback are the length of the two strings, in bytes. The collating
6330
** function must return an integer that is negative, zero, or positive
6331
** if the first string is less than, equal to, or greater than the second,
6332
** respectively.  A collating function must always return the same answer
6333
** given the same inputs.  If two or more collating functions are registered
6334
** to the same collation name (using different eTextRep values) then all
6335
** must give an equivalent answer when invoked with equivalent strings.
6336
** The collating function must obey the following properties for all
6337
** strings A, B, and C:
6338
**
6339
** <ol>
6340
** <li> If A==B then B==A.
6341
** <li> If A==B and B==C then A==C.
6342
** <li> If A&lt;B THEN B&gt;A.
6343
** <li> If A&lt;B and B&lt;C then A&lt;C.
6344
** </ol>
6345
**
6346
** If a collating function fails any of the above constraints and that
6347
** collating function is registered and used, then the behavior of SQLite
6348
** is undefined.
6349
**
6350
** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
6351
** with the addition that the xDestroy callback is invoked on pArg when
6352
** the collating function is deleted.
6353
** ^Collating functions are deleted when they are overridden by later
6354
** calls to the collation creation functions or when the
6355
** [database connection] is closed using [sqlite3_close()].
6356
**
6357
** ^The xDestroy callback is <u>not</u> called if the
6358
** sqlite3_create_collation_v2() function fails.  Applications that invoke
6359
** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
6360
** check the return code and dispose of the application data pointer
6361
** themselves rather than expecting SQLite to deal with it for them.
6362
** This is different from every other SQLite interface.  The inconsistency
6363
** is unfortunate but cannot be changed without breaking backwards
6364
** compatibility.
6365
**
6366
** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
6367
*/
6368
SQLITE_API int sqlite3_create_collation(
6369
  sqlite3*,
6370
  const char *zName,
6371
  int eTextRep,
6372
  void *pArg,
6373
  int(*xCompare)(void*,int,const void*,int,const void*)
6374
);
6375
SQLITE_API int sqlite3_create_collation_v2(
6376
  sqlite3*,
6377
  const char *zName,
6378
  int eTextRep,
6379
  void *pArg,
6380
  int(*xCompare)(void*,int,const void*,int,const void*),
6381
  void(*xDestroy)(void*)
6382
);
6383
SQLITE_API int sqlite3_create_collation16(
6384
  sqlite3*,
6385
  const void *zName,
6386
  int eTextRep,
6387
  void *pArg,
6388
  int(*xCompare)(void*,int,const void*,int,const void*)
6389
);
6390
6391
/*
6392
** CAPI3REF: Collation Needed Callbacks
6393
** METHOD: sqlite3
6394
**
6395
** ^To avoid having to register all collation sequences before a database
6396
** can be used, a single callback function may be registered with the
6397
** [database connection] to be invoked whenever an undefined collation
6398
** sequence is required.
6399
**
6400
** ^If the function is registered using the sqlite3_collation_needed() API,
6401
** then it is passed the names of undefined collation sequences as strings
6402
** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
6403
** the names are passed as UTF-16 in machine native byte order.
6404
** ^A call to either function replaces the existing collation-needed callback.
6405
**
6406
** ^(When the callback is invoked, the first argument passed is a copy
6407
** of the second argument to sqlite3_collation_needed() or
6408
** sqlite3_collation_needed16().  The second argument is the database
6409
** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
6410
** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
6411
** sequence function required.  The fourth parameter is the name of the
6412
** required collation sequence.)^
6413
**
6414
** The callback function should register the desired collation using
6415
** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
6416
** [sqlite3_create_collation_v2()].
6417
*/
6418
SQLITE_API int sqlite3_collation_needed(
6419
  sqlite3*,
6420
  void*,
6421
  void(*)(void*,sqlite3*,int eTextRep,const char*)
6422
);
6423
SQLITE_API int sqlite3_collation_needed16(
6424
  sqlite3*,
6425
  void*,
6426
  void(*)(void*,sqlite3*,int eTextRep,const void*)
6427
);
6428
6429
#ifdef SQLITE_ENABLE_CEROD
6430
/*
6431
** Specify the activation key for a CEROD database.  Unless
6432
** activated, none of the CEROD routines will work.
6433
*/
6434
SQLITE_API void sqlite3_activate_cerod(
6435
  const char *zPassPhrase        /* Activation phrase */
6436
);
6437
#endif
6438
6439
/*
6440
** CAPI3REF: Suspend Execution For A Short Time
6441
**
6442
** The sqlite3_sleep() function causes the current thread to suspend execution
6443
** for at least a number of milliseconds specified in its parameter.
6444
**
6445
** If the operating system does not support sleep requests with
6446
** millisecond time resolution, then the time will be rounded up to
6447
** the nearest second. The number of milliseconds of sleep actually
6448
** requested from the operating system is returned.
6449
**
6450
** ^SQLite implements this interface by calling the xSleep()
6451
** method of the default [sqlite3_vfs] object.  If the xSleep() method
6452
** of the default VFS is not implemented correctly, or not implemented at
6453
** all, then the behavior of sqlite3_sleep() may deviate from the description
6454
** in the previous paragraphs.
6455
**
6456
** If a negative argument is passed to sqlite3_sleep() the results vary by
6457
** VFS and operating system.  Some system treat a negative argument as an
6458
** instruction to sleep forever.  Others understand it to mean do not sleep
6459
** at all. ^In SQLite version 3.42.0 and later, a negative
6460
** argument passed into sqlite3_sleep() is changed to zero before it is relayed
6461
** down into the xSleep method of the VFS.
6462
*/
6463
SQLITE_API int sqlite3_sleep(int);
6464
6465
/*
6466
** CAPI3REF: Name Of The Folder Holding Temporary Files
6467
**
6468
** ^(If this global variable is made to point to a string which is
6469
** the name of a folder (a.k.a. directory), then all temporary files
6470
** created by SQLite when using a built-in [sqlite3_vfs | VFS]
6471
** will be placed in that directory.)^  ^If this variable
6472
** is a NULL pointer, then SQLite performs a search for an appropriate
6473
** temporary file directory.
6474
**
6475
** Applications are strongly discouraged from using this global variable.
6476
** It is required to set a temporary folder on Windows Runtime (WinRT).
6477
** But for all other platforms, it is highly recommended that applications
6478
** neither read nor write this variable.  This global variable is a relic
6479
** that exists for backwards compatibility of legacy applications and should
6480
** be avoided in new projects.
6481
**
6482
** It is not safe to read or modify this variable in more than one
6483
** thread at a time.  It is not safe to read or modify this variable
6484
** if a [database connection] is being used at the same time in a separate
6485
** thread.
6486
** It is intended that this variable be set once
6487
** as part of process initialization and before any SQLite interface
6488
** routines have been called and that this variable remain unchanged
6489
** thereafter.
6490
**
6491
** ^The [temp_store_directory pragma] may modify this variable and cause
6492
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
6493
** the [temp_store_directory pragma] always assumes that any string
6494
** that this variable points to is held in memory obtained from
6495
** [sqlite3_malloc] and the pragma may attempt to free that memory
6496
** using [sqlite3_free].
6497
** Hence, if this variable is modified directly, either it should be
6498
** made NULL or made to point to memory obtained from [sqlite3_malloc]
6499
** or else the use of the [temp_store_directory pragma] should be avoided.
6500
** Except when requested by the [temp_store_directory pragma], SQLite
6501
** does not free the memory that sqlite3_temp_directory points to.  If
6502
** the application wants that memory to be freed, it must do
6503
** so itself, taking care to only do so after all [database connection]
6504
** objects have been destroyed.
6505
**
6506
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
6507
** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
6508
** features that require the use of temporary files may fail.  Here is an
6509
** example of how to do this using C++ with the Windows Runtime:
6510
**
6511
** <blockquote><pre>
6512
** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
6513
** &nbsp;     TemporaryFolder->Path->Data();
6514
** char zPathBuf&#91;MAX_PATH + 1&#93;;
6515
** memset(zPathBuf, 0, sizeof(zPathBuf));
6516
** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
6517
** &nbsp;     NULL, NULL);
6518
** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
6519
** </pre></blockquote>
6520
*/
6521
SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
6522
6523
/*
6524
** CAPI3REF: Name Of The Folder Holding Database Files
6525
**
6526
** ^(If this global variable is made to point to a string which is
6527
** the name of a folder (a.k.a. directory), then all database files
6528
** specified with a relative pathname and created or accessed by
6529
** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
6530
** to be relative to that directory.)^ ^If this variable is a NULL
6531
** pointer, then SQLite assumes that all database files specified
6532
** with a relative pathname are relative to the current directory
6533
** for the process.  Only the windows VFS makes use of this global
6534
** variable; it is ignored by the unix VFS.
6535
**
6536
** Changing the value of this variable while a database connection is
6537
** open can result in a corrupt database.
6538
**
6539
** It is not safe to read or modify this variable in more than one
6540
** thread at a time.  It is not safe to read or modify this variable
6541
** if a [database connection] is being used at the same time in a separate
6542
** thread.
6543
** It is intended that this variable be set once
6544
** as part of process initialization and before any SQLite interface
6545
** routines have been called and that this variable remain unchanged
6546
** thereafter.
6547
**
6548
** ^The [data_store_directory pragma] may modify this variable and cause
6549
** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
6550
** the [data_store_directory pragma] always assumes that any string
6551
** that this variable points to is held in memory obtained from
6552
** [sqlite3_malloc] and the pragma may attempt to free that memory
6553
** using [sqlite3_free].
6554
** Hence, if this variable is modified directly, either it should be
6555
** made NULL or made to point to memory obtained from [sqlite3_malloc]
6556
** or else the use of the [data_store_directory pragma] should be avoided.
6557
*/
6558
SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
6559
6560
/*
6561
** CAPI3REF: Win32 Specific Interface
6562
**
6563
** These interfaces are available only on Windows.  The
6564
** [sqlite3_win32_set_directory] interface is used to set the value associated
6565
** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to
6566
** zValue, depending on the value of the type parameter.  The zValue parameter
6567
** should be NULL to cause the previous value to be freed via [sqlite3_free];
6568
** a non-NULL value will be copied into memory obtained from [sqlite3_malloc]
6569
** prior to being used.  The [sqlite3_win32_set_directory] interface returns
6570
** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported,
6571
** or [SQLITE_NOMEM] if memory could not be allocated.  The value of the
6572
** [sqlite3_data_directory] variable is intended to act as a replacement for
6573
** the current directory on the sub-platforms of Win32 where that concept is
6574
** not present, e.g. WinRT and UWP.  The [sqlite3_win32_set_directory8] and
6575
** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the
6576
** sqlite3_win32_set_directory interface except the string parameter must be
6577
** UTF-8 or UTF-16, respectively.
6578
*/
6579
SQLITE_API int sqlite3_win32_set_directory(
6580
  unsigned long type, /* Identifier for directory being set or reset */
6581
  void *zValue        /* New value for directory being set or reset */
6582
);
6583
SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue);
6584
SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue);
6585
6586
/*
6587
** CAPI3REF: Win32 Directory Types
6588
**
6589
** These macros are only available on Windows.  They define the allowed values
6590
** for the type argument to the [sqlite3_win32_set_directory] interface.
6591
*/
6592
#define SQLITE_WIN32_DATA_DIRECTORY_TYPE  1
6593
#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE  2
6594
6595
/*
6596
** CAPI3REF: Test For Auto-Commit Mode
6597
** KEYWORDS: {autocommit mode}
6598
** METHOD: sqlite3
6599
**
6600
** ^The sqlite3_get_autocommit() interface returns non-zero or
6601
** zero if the given database connection is or is not in autocommit mode,
6602
** respectively.  ^Autocommit mode is on by default.
6603
** ^Autocommit mode is disabled by a [BEGIN] statement.
6604
** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
6605
**
6606
** If certain kinds of errors occur on a statement within a multi-statement
6607
** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
6608
** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
6609
** transaction might be rolled back automatically.  The only way to
6610
** find out whether SQLite automatically rolled back the transaction after
6611
** an error is to use this function.
6612
**
6613
** If another thread changes the autocommit status of the database
6614
** connection while this routine is running, then the return value
6615
** is undefined.
6616
*/
6617
SQLITE_API int sqlite3_get_autocommit(sqlite3*);
6618
6619
/*
6620
** CAPI3REF: Find The Database Handle Of A Prepared Statement
6621
** METHOD: sqlite3_stmt
6622
**
6623
** ^The sqlite3_db_handle interface returns the [database connection] handle
6624
** to which a [prepared statement] belongs.  ^The [database connection]
6625
** returned by sqlite3_db_handle is the same [database connection]
6626
** that was the first argument
6627
** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
6628
** create the statement in the first place.
6629
*/
6630
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
6631
6632
/*
6633
** CAPI3REF: Return The Schema Name For A Database Connection
6634
** METHOD: sqlite3
6635
**
6636
** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name
6637
** for the N-th database on database connection D, or a NULL pointer of N is
6638
** out of range.  An N value of 0 means the main database file.  An N of 1 is
6639
** the "temp" schema.  Larger values of N correspond to various ATTACH-ed
6640
** databases.
6641
**
6642
** Space to hold the string that is returned by sqlite3_db_name() is managed
6643
** by SQLite itself.  The string might be deallocated by any operation that
6644
** changes the schema, including [ATTACH] or [DETACH] or calls to
6645
** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that
6646
** occur on a different thread.  Applications that need to
6647
** remember the string long-term should make their own copy.  Applications that
6648
** are accessing the same database connection simultaneously on multiple
6649
** threads should mutex-protect calls to this API and should make their own
6650
** private copy of the result prior to releasing the mutex.
6651
*/
6652
SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N);
6653
6654
/*
6655
** CAPI3REF: Return The Filename For A Database Connection
6656
** METHOD: sqlite3
6657
**
6658
** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename
6659
** associated with database N of connection D.
6660
** ^If there is no attached database N on the database
6661
** connection D, or if database N is a temporary or in-memory database, then
6662
** this function will return either a NULL pointer or an empty string.
6663
**
6664
** ^The string value returned by this routine is owned and managed by
6665
** the database connection.  ^The value will be valid until the database N
6666
** is [DETACH]-ed or until the database connection closes.
6667
**
6668
** ^The filename returned by this function is the output of the
6669
** xFullPathname method of the [VFS].  ^In other words, the filename
6670
** will be an absolute pathname, even if the filename used
6671
** to open the database originally was a URI or relative pathname.
6672
**
6673
** If the filename pointer returned by this routine is not NULL, then it
6674
** can be used as the filename input parameter to these routines:
6675
** <ul>
6676
** <li> [sqlite3_uri_parameter()]
6677
** <li> [sqlite3_uri_boolean()]
6678
** <li> [sqlite3_uri_int64()]
6679
** <li> [sqlite3_filename_database()]
6680
** <li> [sqlite3_filename_journal()]
6681
** <li> [sqlite3_filename_wal()]
6682
** </ul>
6683
*/
6684
SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName);
6685
6686
/*
6687
** CAPI3REF: Determine if a database is read-only
6688
** METHOD: sqlite3
6689
**
6690
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
6691
** of connection D is read-only, 0 if it is read/write, or -1 if N is not
6692
** the name of a database on connection D.
6693
*/
6694
SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
6695
6696
/*
6697
** CAPI3REF: Determine the transaction state of a database
6698
** METHOD: sqlite3
6699
**
6700
** ^The sqlite3_txn_state(D,S) interface returns the current
6701
** [transaction state] of schema S in database connection D.  ^If S is NULL,
6702
** then the highest transaction state of any schema on database connection D
6703
** is returned.  Transaction states are (in order of lowest to highest):
6704
** <ol>
6705
** <li value="0"> SQLITE_TXN_NONE
6706
** <li value="1"> SQLITE_TXN_READ
6707
** <li value="2"> SQLITE_TXN_WRITE
6708
** </ol>
6709
** ^If the S argument to sqlite3_txn_state(D,S) is not the name of
6710
** a valid schema, then -1 is returned.
6711
*/
6712
SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema);
6713
6714
/*
6715
** CAPI3REF: Allowed return values from sqlite3_txn_state()
6716
** KEYWORDS: {transaction state}
6717
**
6718
** These constants define the current transaction state of a database file.
6719
** ^The [sqlite3_txn_state(D,S)] interface returns one of these
6720
** constants in order to describe the transaction state of schema S
6721
** in [database connection] D.
6722
**
6723
** <dl>
6724
** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt>
6725
** <dd>The SQLITE_TXN_NONE state means that no transaction is currently
6726
** pending.</dd>
6727
**
6728
** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt>
6729
** <dd>The SQLITE_TXN_READ state means that the database is currently
6730
** in a read transaction.  Content has been read from the database file
6731
** but nothing in the database file has changed.  The transaction state
6732
** will advanced to SQLITE_TXN_WRITE if any changes occur and there are
6733
** no other conflicting concurrent write transactions.  The transaction
6734
** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or
6735
** [COMMIT].</dd>
6736
**
6737
** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt>
6738
** <dd>The SQLITE_TXN_WRITE state means that the database is currently
6739
** in a write transaction.  Content has been written to the database file
6740
** but has not yet committed.  The transaction state will change to
6741
** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd>
6742
*/
6743
#define SQLITE_TXN_NONE  0
6744
#define SQLITE_TXN_READ  1
6745
#define SQLITE_TXN_WRITE 2
6746
6747
/*
6748
** CAPI3REF: Find the next prepared statement
6749
** METHOD: sqlite3
6750
**
6751
** ^This interface returns a pointer to the next [prepared statement] after
6752
** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
6753
** then this interface returns a pointer to the first prepared statement
6754
** associated with the database connection pDb.  ^If no prepared statement
6755
** satisfies the conditions of this routine, it returns NULL.
6756
**
6757
** The [database connection] pointer D in a call to
6758
** [sqlite3_next_stmt(D,S)] must refer to an open database
6759
** connection and in particular must not be a NULL pointer.
6760
*/
6761
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
6762
6763
/*
6764
** CAPI3REF: Commit And Rollback Notification Callbacks
6765
** METHOD: sqlite3
6766
**
6767
** ^The sqlite3_commit_hook() interface registers a callback
6768
** function to be invoked whenever a transaction is [COMMIT | committed].
6769
** ^Any callback set by a previous call to sqlite3_commit_hook()
6770
** for the same database connection is overridden.
6771
** ^The sqlite3_rollback_hook() interface registers a callback
6772
** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
6773
** ^Any callback set by a previous call to sqlite3_rollback_hook()
6774
** for the same database connection is overridden.
6775
** ^The pArg argument is passed through to the callback.
6776
** ^If the callback on a commit hook function returns non-zero,
6777
** then the commit is converted into a rollback.
6778
**
6779
** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
6780
** return the P argument from the previous call of the same function
6781
** on the same [database connection] D, or NULL for
6782
** the first call for each function on D.
6783
**
6784
** The commit and rollback hook callbacks are not reentrant.
6785
** The callback implementation must not do anything that will modify
6786
** the database connection that invoked the callback.  Any actions
6787
** to modify the database connection must be deferred until after the
6788
** completion of the [sqlite3_step()] call that triggered the commit
6789
** or rollback hook in the first place.
6790
** Note that running any other SQL statements, including SELECT statements,
6791
** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
6792
** the database connections for the meaning of "modify" in this paragraph.
6793
**
6794
** ^Registering a NULL function disables the callback.
6795
**
6796
** ^When the commit hook callback routine returns zero, the [COMMIT]
6797
** operation is allowed to continue normally.  ^If the commit hook
6798
** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
6799
** ^The rollback hook is invoked on a rollback that results from a commit
6800
** hook returning non-zero, just as it would be with any other rollback.
6801
**
6802
** ^For the purposes of this API, a transaction is said to have been
6803
** rolled back if an explicit "ROLLBACK" statement is executed, or
6804
** an error or constraint causes an implicit rollback to occur.
6805
** ^The rollback callback is not invoked if a transaction is
6806
** automatically rolled back because the database connection is closed.
6807
**
6808
** See also the [sqlite3_update_hook()] interface.
6809
*/
6810
SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
6811
SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
6812
6813
/*
6814
** CAPI3REF: Autovacuum Compaction Amount Callback
6815
** METHOD: sqlite3
6816
**
6817
** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback
6818
** function C that is invoked prior to each autovacuum of the database
6819
** file.  ^The callback is passed a copy of the generic data pointer (P),
6820
** the schema-name of the attached database that is being autovacuumed,
6821
** the size of the database file in pages, the number of free pages,
6822
** and the number of bytes per page, respectively.  The callback should
6823
** return the number of free pages that should be removed by the
6824
** autovacuum.  ^If the callback returns zero, then no autovacuum happens.
6825
** ^If the value returned is greater than or equal to the number of
6826
** free pages, then a complete autovacuum happens.
6827
**
6828
** <p>^If there are multiple ATTACH-ed database files that are being
6829
** modified as part of a transaction commit, then the autovacuum pages
6830
** callback is invoked separately for each file.
6831
**
6832
** <p><b>The callback is not reentrant.</b> The callback function should
6833
** not attempt to invoke any other SQLite interface.  If it does, bad
6834
** things may happen, including segmentation faults and corrupt database
6835
** files.  The callback function should be a simple function that
6836
** does some arithmetic on its input parameters and returns a result.
6837
**
6838
** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional
6839
** destructor for the P parameter.  ^If X is not NULL, then X(P) is
6840
** invoked whenever the database connection closes or when the callback
6841
** is overwritten by another invocation of sqlite3_autovacuum_pages().
6842
**
6843
** <p>^There is only one autovacuum pages callback per database connection.
6844
** ^Each call to the sqlite3_autovacuum_pages() interface overrides all
6845
** previous invocations for that database connection.  ^If the callback
6846
** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer,
6847
** then the autovacuum steps callback is canceled.  The return value
6848
** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might
6849
** be some other error code if something goes wrong.  The current
6850
** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other
6851
** return codes might be added in future releases.
6852
**
6853
** <p>If no autovacuum pages callback is specified (the usual case) or
6854
** a NULL pointer is provided for the callback,
6855
** then the default behavior is to vacuum all free pages.  So, in other
6856
** words, the default behavior is the same as if the callback function
6857
** were something like this:
6858
**
6859
** <blockquote><pre>
6860
** &nbsp;   unsigned int demonstration_autovac_pages_callback(
6861
** &nbsp;     void *pClientData,
6862
** &nbsp;     const char *zSchema,
6863
** &nbsp;     unsigned int nDbPage,
6864
** &nbsp;     unsigned int nFreePage,
6865
** &nbsp;     unsigned int nBytePerPage
6866
** &nbsp;   ){
6867
** &nbsp;     return nFreePage;
6868
** &nbsp;   }
6869
** </pre></blockquote>
6870
*/
6871
SQLITE_API int sqlite3_autovacuum_pages(
6872
  sqlite3 *db,
6873
  unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int),
6874
  void*,
6875
  void(*)(void*)
6876
);
6877
6878
6879
/*
6880
** CAPI3REF: Data Change Notification Callbacks
6881
** METHOD: sqlite3
6882
**
6883
** ^The sqlite3_update_hook() interface registers a callback function
6884
** with the [database connection] identified by the first argument
6885
** to be invoked whenever a row is updated, inserted or deleted in
6886
** a [rowid table].
6887
** ^Any callback set by a previous call to this function
6888
** for the same database connection is overridden.
6889
**
6890
** ^The second argument is a pointer to the function to invoke when a
6891
** row is updated, inserted or deleted in a rowid table.
6892
** ^The first argument to the callback is a copy of the third argument
6893
** to sqlite3_update_hook().
6894
** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
6895
** or [SQLITE_UPDATE], depending on the operation that caused the callback
6896
** to be invoked.
6897
** ^The third and fourth arguments to the callback contain pointers to the
6898
** database and table name containing the affected row.
6899
** ^The final callback parameter is the [rowid] of the row.
6900
** ^In the case of an update, this is the [rowid] after the update takes place.
6901
**
6902
** ^(The update hook is not invoked when internal system tables are
6903
** modified (i.e. sqlite_sequence).)^
6904
** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
6905
**
6906
** ^In the current implementation, the update hook
6907
** is not invoked when conflicting rows are deleted because of an
6908
** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
6909
** invoked when rows are deleted using the [truncate optimization].
6910
** The exceptions defined in this paragraph might change in a future
6911
** release of SQLite.
6912
**
6913
** Whether the update hook is invoked before or after the
6914
** corresponding change is currently unspecified and may differ
6915
** depending on the type of change. Do not rely on the order of the
6916
** hook call with regards to the final result of the operation which
6917
** triggers the hook.
6918
**
6919
** The update hook implementation must not do anything that will modify
6920
** the database connection that invoked the update hook.  Any actions
6921
** to modify the database connection must be deferred until after the
6922
** completion of the [sqlite3_step()] call that triggered the update hook.
6923
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
6924
** database connections for the meaning of "modify" in this paragraph.
6925
**
6926
** ^The sqlite3_update_hook(D,C,P) function
6927
** returns the P argument from the previous call
6928
** on the same [database connection] D, or NULL for
6929
** the first call on D.
6930
**
6931
** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
6932
** and [sqlite3_preupdate_hook()] interfaces.
6933
*/
6934
SQLITE_API void *sqlite3_update_hook(
6935
  sqlite3*,
6936
  void(*)(void *,int ,char const *,char const *,sqlite3_int64),
6937
  void*
6938
);
6939
6940
/*
6941
** CAPI3REF: Enable Or Disable Shared Pager Cache
6942
**
6943
** ^(This routine enables or disables the sharing of the database cache
6944
** and schema data structures between [database connection | connections]
6945
** to the same database. Sharing is enabled if the argument is true
6946
** and disabled if the argument is false.)^
6947
**
6948
** This interface is omitted if SQLite is compiled with
6949
** [-DSQLITE_OMIT_SHARED_CACHE].  The [-DSQLITE_OMIT_SHARED_CACHE]
6950
** compile-time option is recommended because the
6951
** [use of shared cache mode is discouraged].
6952
**
6953
** ^Cache sharing is enabled and disabled for an entire process.
6954
** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
6955
** In prior versions of SQLite,
6956
** sharing was enabled or disabled for each thread separately.
6957
**
6958
** ^(The cache sharing mode set by this interface effects all subsequent
6959
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
6960
** Existing database connections continue to use the sharing mode
6961
** that was in effect at the time they were opened.)^
6962
**
6963
** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
6964
** successfully.  An [error code] is returned otherwise.)^
6965
**
6966
** ^Shared cache is disabled by default. It is recommended that it stay
6967
** that way.  In other words, do not use this routine.  This interface
6968
** continues to be provided for historical compatibility, but its use is
6969
** discouraged.  Any use of shared cache is discouraged.  If shared cache
6970
** must be used, it is recommended that shared cache only be enabled for
6971
** individual database connections using the [sqlite3_open_v2()] interface
6972
** with the [SQLITE_OPEN_SHAREDCACHE] flag.
6973
**
6974
** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
6975
** and will always return SQLITE_MISUSE. On those systems,
6976
** shared cache mode should be enabled per-database connection via
6977
** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
6978
**
6979
** This interface is threadsafe on processors where writing a
6980
** 32-bit integer is atomic.
6981
**
6982
** See Also:  [SQLite Shared-Cache Mode]
6983
*/
6984
SQLITE_API int sqlite3_enable_shared_cache(int);
6985
6986
/*
6987
** CAPI3REF: Attempt To Free Heap Memory
6988
**
6989
** ^The sqlite3_release_memory() interface attempts to free N bytes
6990
** of heap memory by deallocating non-essential memory allocations
6991
** held by the database library.   Memory used to cache database
6992
** pages to improve performance is an example of non-essential memory.
6993
** ^sqlite3_release_memory() returns the number of bytes actually freed,
6994
** which might be more or less than the amount requested.
6995
** ^The sqlite3_release_memory() routine is a no-op returning zero
6996
** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
6997
**
6998
** See also: [sqlite3_db_release_memory()]
6999
*/
7000
SQLITE_API int sqlite3_release_memory(int);
7001
7002
/*
7003
** CAPI3REF: Free Memory Used By A Database Connection
7004
** METHOD: sqlite3
7005
**
7006
** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
7007
** memory as possible from database connection D. Unlike the
7008
** [sqlite3_release_memory()] interface, this interface is in effect even
7009
** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
7010
** omitted.
7011
**
7012
** See also: [sqlite3_release_memory()]
7013
*/
7014
SQLITE_API int sqlite3_db_release_memory(sqlite3*);
7015
7016
/*
7017
** CAPI3REF: Impose A Limit On Heap Size
7018
**
7019
** These interfaces impose limits on the amount of heap memory that will be
7020
** by all database connections within a single process.
7021
**
7022
** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
7023
** soft limit on the amount of heap memory that may be allocated by SQLite.
7024
** ^SQLite strives to keep heap memory utilization below the soft heap
7025
** limit by reducing the number of pages held in the page cache
7026
** as heap memory usages approaches the limit.
7027
** ^The soft heap limit is "soft" because even though SQLite strives to stay
7028
** below the limit, it will exceed the limit rather than generate
7029
** an [SQLITE_NOMEM] error.  In other words, the soft heap limit
7030
** is advisory only.
7031
**
7032
** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of
7033
** N bytes on the amount of memory that will be allocated.  ^The
7034
** sqlite3_hard_heap_limit64(N) interface is similar to
7035
** sqlite3_soft_heap_limit64(N) except that memory allocations will fail
7036
** when the hard heap limit is reached.
7037
**
7038
** ^The return value from both sqlite3_soft_heap_limit64() and
7039
** sqlite3_hard_heap_limit64() is the size of
7040
** the heap limit prior to the call, or negative in the case of an
7041
** error.  ^If the argument N is negative
7042
** then no change is made to the heap limit.  Hence, the current
7043
** size of heap limits can be determined by invoking
7044
** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1).
7045
**
7046
** ^Setting the heap limits to zero disables the heap limiter mechanism.
7047
**
7048
** ^The soft heap limit may not be greater than the hard heap limit.
7049
** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N)
7050
** is invoked with a value of N that is greater than the hard heap limit,
7051
** the soft heap limit is set to the value of the hard heap limit.
7052
** ^The soft heap limit is automatically enabled whenever the hard heap
7053
** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and
7054
** the soft heap limit is outside the range of 1..N, then the soft heap
7055
** limit is set to N.  ^Invoking sqlite3_soft_heap_limit64(0) when the
7056
** hard heap limit is enabled makes the soft heap limit equal to the
7057
** hard heap limit.
7058
**
7059
** The memory allocation limits can also be adjusted using
7060
** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit].
7061
**
7062
** ^(The heap limits are not enforced in the current implementation
7063
** if one or more of following conditions are true:
7064
**
7065
** <ul>
7066
** <li> The limit value is set to zero.
7067
** <li> Memory accounting is disabled using a combination of the
7068
**      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
7069
**      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
7070
** <li> An alternative page cache implementation is specified using
7071
**      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
7072
** <li> The page cache allocates from its own memory pool supplied
7073
**      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
7074
**      from the heap.
7075
** </ul>)^
7076
**
7077
** The circumstances under which SQLite will enforce the heap limits may
7078
** changes in future releases of SQLite.
7079
*/
7080
SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
7081
SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N);
7082
7083
/*
7084
** CAPI3REF: Deprecated Soft Heap Limit Interface
7085
** DEPRECATED
7086
**
7087
** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
7088
** interface.  This routine is provided for historical compatibility
7089
** only.  All new applications should use the
7090
** [sqlite3_soft_heap_limit64()] interface rather than this one.
7091
*/
7092
SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
7093
7094
7095
/*
7096
** CAPI3REF: Extract Metadata About A Column Of A Table
7097
** METHOD: sqlite3
7098
**
7099
** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
7100
** information about column C of table T in database D
7101
** on [database connection] X.)^  ^The sqlite3_table_column_metadata()
7102
** interface returns SQLITE_OK and fills in the non-NULL pointers in
7103
** the final five arguments with appropriate values if the specified
7104
** column exists.  ^The sqlite3_table_column_metadata() interface returns
7105
** SQLITE_ERROR if the specified column does not exist.
7106
** ^If the column-name parameter to sqlite3_table_column_metadata() is a
7107
** NULL pointer, then this routine simply checks for the existence of the
7108
** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
7109
** does not.  If the table name parameter T in a call to
7110
** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
7111
** undefined behavior.
7112
**
7113
** ^The column is identified by the second, third and fourth parameters to
7114
** this function. ^(The second parameter is either the name of the database
7115
** (i.e. "main", "temp", or an attached database) containing the specified
7116
** table or NULL.)^ ^If it is NULL, then all attached databases are searched
7117
** for the table using the same algorithm used by the database engine to
7118
** resolve unqualified table references.
7119
**
7120
** ^The third and fourth parameters to this function are the table and column
7121
** name of the desired column, respectively.
7122
**
7123
** ^Metadata is returned by writing to the memory locations passed as the 5th
7124
** and subsequent parameters to this function. ^Any of these arguments may be
7125
** NULL, in which case the corresponding element of metadata is omitted.
7126
**
7127
** ^(<blockquote>
7128
** <table border="1">
7129
** <tr><th> Parameter <th> Output<br>Type <th>  Description
7130
**
7131
** <tr><td> 5th <td> const char* <td> Data type
7132
** <tr><td> 6th <td> const char* <td> Name of default collation sequence
7133
** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
7134
** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
7135
** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
7136
** </table>
7137
** </blockquote>)^
7138
**
7139
** ^The memory pointed to by the character pointers returned for the
7140
** declaration type and collation sequence is valid until the next
7141
** call to any SQLite API function.
7142
**
7143
** ^If the specified table is actually a view, an [error code] is returned.
7144
**
7145
** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
7146
** is not a [WITHOUT ROWID] table and an
7147
** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
7148
** parameters are set for the explicitly declared column. ^(If there is no
7149
** [INTEGER PRIMARY KEY] column, then the outputs
7150
** for the [rowid] are set as follows:
7151
**
7152
** <pre>
7153
**     data type: "INTEGER"
7154
**     collation sequence: "BINARY"
7155
**     not null: 0
7156
**     primary key: 1
7157
**     auto increment: 0
7158
** </pre>)^
7159
**
7160
** ^This function causes all database schemas to be read from disk and
7161
** parsed, if that has not already been done, and returns an error if
7162
** any errors are encountered while loading the schema.
7163
*/
7164
SQLITE_API int sqlite3_table_column_metadata(
7165
  sqlite3 *db,                /* Connection handle */
7166
  const char *zDbName,        /* Database name or NULL */
7167
  const char *zTableName,     /* Table name */
7168
  const char *zColumnName,    /* Column name */
7169
  char const **pzDataType,    /* OUTPUT: Declared data type */
7170
  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
7171
  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
7172
  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
7173
  int *pAutoinc               /* OUTPUT: True if column is auto-increment */
7174
);
7175
7176
/*
7177
** CAPI3REF: Load An Extension
7178
** METHOD: sqlite3
7179
**
7180
** ^This interface loads an SQLite extension library from the named file.
7181
**
7182
** ^The sqlite3_load_extension() interface attempts to load an
7183
** [SQLite extension] library contained in the file zFile.  If
7184
** the file cannot be loaded directly, attempts are made to load
7185
** with various operating-system specific extensions added.
7186
** So for example, if "samplelib" cannot be loaded, then names like
7187
** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
7188
** be tried also.
7189
**
7190
** ^The entry point is zProc.
7191
** ^(zProc may be 0, in which case SQLite will try to come up with an
7192
** entry point name on its own.  It first tries "sqlite3_extension_init".
7193
** If that does not work, it constructs a name "sqlite3_X_init" where the
7194
** X is consists of the lower-case equivalent of all ASCII alphabetic
7195
** characters in the filename from the last "/" to the first following
7196
** "." and omitting any initial "lib".)^
7197
** ^The sqlite3_load_extension() interface returns
7198
** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
7199
** ^If an error occurs and pzErrMsg is not 0, then the
7200
** [sqlite3_load_extension()] interface shall attempt to
7201
** fill *pzErrMsg with error message text stored in memory
7202
** obtained from [sqlite3_malloc()]. The calling function
7203
** should free this memory by calling [sqlite3_free()].
7204
**
7205
** ^Extension loading must be enabled using
7206
** [sqlite3_enable_load_extension()] or
7207
** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
7208
** prior to calling this API,
7209
** otherwise an error will be returned.
7210
**
7211
** <b>Security warning:</b> It is recommended that the
7212
** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
7213
** interface.  The use of the [sqlite3_enable_load_extension()] interface
7214
** should be avoided.  This will keep the SQL function [load_extension()]
7215
** disabled and prevent SQL injections from giving attackers
7216
** access to extension loading capabilities.
7217
**
7218
** See also the [load_extension() SQL function].
7219
*/
7220
SQLITE_API int sqlite3_load_extension(
7221
  sqlite3 *db,          /* Load the extension into this database connection */
7222
  const char *zFile,    /* Name of the shared library containing extension */
7223
  const char *zProc,    /* Entry point.  Derived from zFile if 0 */
7224
  char **pzErrMsg       /* Put error message here if not 0 */
7225
);
7226
7227
/*
7228
** CAPI3REF: Enable Or Disable Extension Loading
7229
** METHOD: sqlite3
7230
**
7231
** ^So as not to open security holes in older applications that are
7232
** unprepared to deal with [extension loading], and as a means of disabling
7233
** [extension loading] while evaluating user-entered SQL, the following API
7234
** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
7235
**
7236
** ^Extension loading is off by default.
7237
** ^Call the sqlite3_enable_load_extension() routine with onoff==1
7238
** to turn extension loading on and call it with onoff==0 to turn
7239
** it back off again.
7240
**
7241
** ^This interface enables or disables both the C-API
7242
** [sqlite3_load_extension()] and the SQL function [load_extension()].
7243
** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
7244
** to enable or disable only the C-API.)^
7245
**
7246
** <b>Security warning:</b> It is recommended that extension loading
7247
** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
7248
** rather than this interface, so the [load_extension()] SQL function
7249
** remains disabled. This will prevent SQL injections from giving attackers
7250
** access to extension loading capabilities.
7251
*/
7252
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
7253
7254
/*
7255
** CAPI3REF: Automatically Load Statically Linked Extensions
7256
**
7257
** ^This interface causes the xEntryPoint() function to be invoked for
7258
** each new [database connection] that is created.  The idea here is that
7259
** xEntryPoint() is the entry point for a statically linked [SQLite extension]
7260
** that is to be automatically loaded into all new database connections.
7261
**
7262
** ^(Even though the function prototype shows that xEntryPoint() takes
7263
** no arguments and returns void, SQLite invokes xEntryPoint() with three
7264
** arguments and expects an integer result as if the signature of the
7265
** entry point where as follows:
7266
**
7267
** <blockquote><pre>
7268
** &nbsp;  int xEntryPoint(
7269
** &nbsp;    sqlite3 *db,
7270
** &nbsp;    const char **pzErrMsg,
7271
** &nbsp;    const struct sqlite3_api_routines *pThunk
7272
** &nbsp;  );
7273
** </pre></blockquote>)^
7274
**
7275
** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
7276
** point to an appropriate error message (obtained from [sqlite3_mprintf()])
7277
** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
7278
** is NULL before calling the xEntryPoint().  ^SQLite will invoke
7279
** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
7280
** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
7281
** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
7282
**
7283
** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
7284
** on the list of automatic extensions is a harmless no-op. ^No entry point
7285
** will be called more than once for each database connection that is opened.
7286
**
7287
** See also: [sqlite3_reset_auto_extension()]
7288
** and [sqlite3_cancel_auto_extension()]
7289
*/
7290
SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
7291
7292
/*
7293
** CAPI3REF: Cancel Automatic Extension Loading
7294
**
7295
** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
7296
** initialization routine X that was registered using a prior call to
7297
** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
7298
** routine returns 1 if initialization routine X was successfully
7299
** unregistered and it returns 0 if X was not on the list of initialization
7300
** routines.
7301
*/
7302
SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
7303
7304
/*
7305
** CAPI3REF: Reset Automatic Extension Loading
7306
**
7307
** ^This interface disables all automatic extensions previously
7308
** registered using [sqlite3_auto_extension()].
7309
*/
7310
SQLITE_API void sqlite3_reset_auto_extension(void);
7311
7312
/*
7313
** Structures used by the virtual table interface
7314
*/
7315
typedef struct sqlite3_vtab sqlite3_vtab;
7316
typedef struct sqlite3_index_info sqlite3_index_info;
7317
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
7318
typedef struct sqlite3_module sqlite3_module;
7319
7320
/*
7321
** CAPI3REF: Virtual Table Object
7322
** KEYWORDS: sqlite3_module {virtual table module}
7323
**
7324
** This structure, sometimes called a "virtual table module",
7325
** defines the implementation of a [virtual table].
7326
** This structure consists mostly of methods for the module.
7327
**
7328
** ^A virtual table module is created by filling in a persistent
7329
** instance of this structure and passing a pointer to that instance
7330
** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
7331
** ^The registration remains valid until it is replaced by a different
7332
** module or until the [database connection] closes.  The content
7333
** of this structure must not change while it is registered with
7334
** any database connection.
7335
*/
7336
struct sqlite3_module {
7337
  int iVersion;
7338
  int (*xCreate)(sqlite3*, void *pAux,
7339
               int argc, const char *const*argv,
7340
               sqlite3_vtab **ppVTab, char**);
7341
  int (*xConnect)(sqlite3*, void *pAux,
7342
               int argc, const char *const*argv,
7343
               sqlite3_vtab **ppVTab, char**);
7344
  int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
7345
  int (*xDisconnect)(sqlite3_vtab *pVTab);
7346
  int (*xDestroy)(sqlite3_vtab *pVTab);
7347
  int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
7348
  int (*xClose)(sqlite3_vtab_cursor*);
7349
  int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
7350
                int argc, sqlite3_value **argv);
7351
  int (*xNext)(sqlite3_vtab_cursor*);
7352
  int (*xEof)(sqlite3_vtab_cursor*);
7353
  int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
7354
  int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
7355
  int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
7356
  int (*xBegin)(sqlite3_vtab *pVTab);
7357
  int (*xSync)(sqlite3_vtab *pVTab);
7358
  int (*xCommit)(sqlite3_vtab *pVTab);
7359
  int (*xRollback)(sqlite3_vtab *pVTab);
7360
  int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
7361
                       void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
7362
                       void **ppArg);
7363
  int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
7364
  /* The methods above are in version 1 of the sqlite_module object. Those
7365
  ** below are for version 2 and greater. */
7366
  int (*xSavepoint)(sqlite3_vtab *pVTab, int);
7367
  int (*xRelease)(sqlite3_vtab *pVTab, int);
7368
  int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
7369
  /* The methods above are in versions 1 and 2 of the sqlite_module object.
7370
  ** Those below are for version 3 and greater. */
7371
  int (*xShadowName)(const char*);
7372
  /* The methods above are in versions 1 through 3 of the sqlite_module object.
7373
  ** Those below are for version 4 and greater. */
7374
  int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema,
7375
                    const char *zTabName, int mFlags, char **pzErr);
7376
};
7377
7378
/*
7379
** CAPI3REF: Virtual Table Indexing Information
7380
** KEYWORDS: sqlite3_index_info
7381
**
7382
** The sqlite3_index_info structure and its substructures is used as part
7383
** of the [virtual table] interface to
7384
** pass information into and receive the reply from the [xBestIndex]
7385
** method of a [virtual table module].  The fields under **Inputs** are the
7386
** inputs to xBestIndex and are read-only.  xBestIndex inserts its
7387
** results into the **Outputs** fields.
7388
**
7389
** ^(The aConstraint[] array records WHERE clause constraints of the form:
7390
**
7391
** <blockquote>column OP expr</blockquote>
7392
**
7393
** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
7394
** stored in aConstraint[].op using one of the
7395
** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
7396
** ^(The index of the column is stored in
7397
** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
7398
** expr on the right-hand side can be evaluated (and thus the constraint
7399
** is usable) and false if it cannot.)^
7400
**
7401
** ^The optimizer automatically inverts terms of the form "expr OP column"
7402
** and makes other simplifications to the WHERE clause in an attempt to
7403
** get as many WHERE clause terms into the form shown above as possible.
7404
** ^The aConstraint[] array only reports WHERE clause terms that are
7405
** relevant to the particular virtual table being queried.
7406
**
7407
** ^Information about the ORDER BY clause is stored in aOrderBy[].
7408
** ^Each term of aOrderBy records a column of the ORDER BY clause.
7409
**
7410
** The colUsed field indicates which columns of the virtual table may be
7411
** required by the current scan. Virtual table columns are numbered from
7412
** zero in the order in which they appear within the CREATE TABLE statement
7413
** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
7414
** the corresponding bit is set within the colUsed mask if the column may be
7415
** required by SQLite. If the table has at least 64 columns and any column
7416
** to the right of the first 63 is required, then bit 63 of colUsed is also
7417
** set. In other words, column iCol may be required if the expression
7418
** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
7419
** non-zero.
7420
**
7421
** The [xBestIndex] method must fill aConstraintUsage[] with information
7422
** about what parameters to pass to xFilter.  ^If argvIndex>0 then
7423
** the right-hand side of the corresponding aConstraint[] is evaluated
7424
** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
7425
** is true, then the constraint is assumed to be fully handled by the
7426
** virtual table and might not be checked again by the byte code.)^ ^(The
7427
** aConstraintUsage[].omit flag is an optimization hint. When the omit flag
7428
** is left in its default setting of false, the constraint will always be
7429
** checked separately in byte code.  If the omit flag is change to true, then
7430
** the constraint may or may not be checked in byte code.  In other words,
7431
** when the omit flag is true there is no guarantee that the constraint will
7432
** not be checked again using byte code.)^
7433
**
7434
** ^The idxNum and idxStr values are recorded and passed into the
7435
** [xFilter] method.
7436
** ^[sqlite3_free()] is used to free idxStr if and only if
7437
** needToFreeIdxStr is true.
7438
**
7439
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
7440
** the correct order to satisfy the ORDER BY clause so that no separate
7441
** sorting step is required.
7442
**
7443
** ^The estimatedCost value is an estimate of the cost of a particular
7444
** strategy. A cost of N indicates that the cost of the strategy is similar
7445
** to a linear scan of an SQLite table with N rows. A cost of log(N)
7446
** indicates that the expense of the operation is similar to that of a
7447
** binary search on a unique indexed field of an SQLite table with N rows.
7448
**
7449
** ^The estimatedRows value is an estimate of the number of rows that
7450
** will be returned by the strategy.
7451
**
7452
** The xBestIndex method may optionally populate the idxFlags field with a
7453
** mask of SQLITE_INDEX_SCAN_* flags. One such flag is
7454
** [SQLITE_INDEX_SCAN_HEX], which if set causes the [EXPLAIN QUERY PLAN]
7455
** output to show the idxNum has hex instead of as decimal.  Another flag is
7456
** SQLITE_INDEX_SCAN_UNIQUE, which if set indicates that the query plan will
7457
** return at most one row.
7458
**
7459
** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
7460
** SQLite also assumes that if a call to the xUpdate() method is made as
7461
** part of the same statement to delete or update a virtual table row and the
7462
** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
7463
** any database changes. In other words, if the xUpdate() returns
7464
** SQLITE_CONSTRAINT, the database contents must be exactly as they were
7465
** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
7466
** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
7467
** the xUpdate method are automatically rolled back by SQLite.
7468
**
7469
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
7470
** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
7471
** If a virtual table extension is
7472
** used with an SQLite version earlier than 3.8.2, the results of attempting
7473
** to read or write the estimatedRows field are undefined (but are likely
7474
** to include crashing the application). The estimatedRows field should
7475
** therefore only be used if [sqlite3_libversion_number()] returns a
7476
** value greater than or equal to 3008002. Similarly, the idxFlags field
7477
** was added for [version 3.9.0] ([dateof:3.9.0]).
7478
** It may therefore only be used if
7479
** sqlite3_libversion_number() returns a value greater than or equal to
7480
** 3009000.
7481
*/
7482
struct sqlite3_index_info {
7483
  /* Inputs */
7484
  int nConstraint;           /* Number of entries in aConstraint */
7485
  struct sqlite3_index_constraint {
7486
     int iColumn;              /* Column constrained.  -1 for ROWID */
7487
     unsigned char op;         /* Constraint operator */
7488
     unsigned char usable;     /* True if this constraint is usable */
7489
     int iTermOffset;          /* Used internally - xBestIndex should ignore */
7490
  } *aConstraint;            /* Table of WHERE clause constraints */
7491
  int nOrderBy;              /* Number of terms in the ORDER BY clause */
7492
  struct sqlite3_index_orderby {
7493
     int iColumn;              /* Column number */
7494
     unsigned char desc;       /* True for DESC.  False for ASC. */
7495
  } *aOrderBy;               /* The ORDER BY clause */
7496
  /* Outputs */
7497
  struct sqlite3_index_constraint_usage {
7498
    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
7499
    unsigned char omit;      /* Do not code a test for this constraint */
7500
  } *aConstraintUsage;
7501
  int idxNum;                /* Number used to identify the index */
7502
  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
7503
  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
7504
  int orderByConsumed;       /* True if output is already ordered */
7505
  double estimatedCost;           /* Estimated cost of using this index */
7506
  /* Fields below are only available in SQLite 3.8.2 and later */
7507
  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
7508
  /* Fields below are only available in SQLite 3.9.0 and later */
7509
  int idxFlags;              /* Mask of SQLITE_INDEX_SCAN_* flags */
7510
  /* Fields below are only available in SQLite 3.10.0 and later */
7511
  sqlite3_uint64 colUsed;    /* Input: Mask of columns used by statement */
7512
};
7513
7514
/*
7515
** CAPI3REF: Virtual Table Scan Flags
7516
**
7517
** Virtual table implementations are allowed to set the
7518
** [sqlite3_index_info].idxFlags field to some combination of
7519
** these bits.
7520
*/
7521
#define SQLITE_INDEX_SCAN_UNIQUE 0x00000001 /* Scan visits at most 1 row */
7522
#define SQLITE_INDEX_SCAN_HEX    0x00000002 /* Display idxNum as hex */
7523
                                            /* in EXPLAIN QUERY PLAN */
7524
7525
/*
7526
** CAPI3REF: Virtual Table Constraint Operator Codes
7527
**
7528
** These macros define the allowed values for the
7529
** [sqlite3_index_info].aConstraint[].op field.  Each value represents
7530
** an operator that is part of a constraint term in the WHERE clause of
7531
** a query that uses a [virtual table].
7532
**
7533
** ^The left-hand operand of the operator is given by the corresponding
7534
** aConstraint[].iColumn field.  ^An iColumn of -1 indicates the left-hand
7535
** operand is the rowid.
7536
** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET
7537
** operators have no left-hand operand, and so for those operators the
7538
** corresponding aConstraint[].iColumn is meaningless and should not be
7539
** used.
7540
**
7541
** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through
7542
** value 255 are reserved to represent functions that are overloaded
7543
** by the [xFindFunction|xFindFunction method] of the virtual table
7544
** implementation.
7545
**
7546
** The right-hand operands for each constraint might be accessible using
7547
** the [sqlite3_vtab_rhs_value()] interface.  Usually the right-hand
7548
** operand is only available if it appears as a single constant literal
7549
** in the input SQL.  If the right-hand operand is another column or an
7550
** expression (even a constant expression) or a parameter, then the
7551
** sqlite3_vtab_rhs_value() probably will not be able to extract it.
7552
** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and
7553
** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand
7554
** and hence calls to sqlite3_vtab_rhs_value() for those operators will
7555
** always return SQLITE_NOTFOUND.
7556
**
7557
** The collating sequence to be used for comparison can be found using
7558
** the [sqlite3_vtab_collation()] interface.  For most real-world virtual
7559
** tables, the collating sequence of constraints does not matter (for example
7560
** because the constraints are numeric) and so the sqlite3_vtab_collation()
7561
** interface is not commonly needed.
7562
*/
7563
#define SQLITE_INDEX_CONSTRAINT_EQ          2
7564
#define SQLITE_INDEX_CONSTRAINT_GT          4
7565
#define SQLITE_INDEX_CONSTRAINT_LE          8
7566
#define SQLITE_INDEX_CONSTRAINT_LT         16
7567
#define SQLITE_INDEX_CONSTRAINT_GE         32
7568
#define SQLITE_INDEX_CONSTRAINT_MATCH      64
7569
#define SQLITE_INDEX_CONSTRAINT_LIKE       65
7570
#define SQLITE_INDEX_CONSTRAINT_GLOB       66
7571
#define SQLITE_INDEX_CONSTRAINT_REGEXP     67
7572
#define SQLITE_INDEX_CONSTRAINT_NE         68
7573
#define SQLITE_INDEX_CONSTRAINT_ISNOT      69
7574
#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL  70
7575
#define SQLITE_INDEX_CONSTRAINT_ISNULL     71
7576
#define SQLITE_INDEX_CONSTRAINT_IS         72
7577
#define SQLITE_INDEX_CONSTRAINT_LIMIT      73
7578
#define SQLITE_INDEX_CONSTRAINT_OFFSET     74
7579
#define SQLITE_INDEX_CONSTRAINT_FUNCTION  150
7580
7581
/*
7582
** CAPI3REF: Register A Virtual Table Implementation
7583
** METHOD: sqlite3
7584
**
7585
** ^These routines are used to register a new [virtual table module] name.
7586
** ^Module names must be registered before
7587
** creating a new [virtual table] using the module and before using a
7588
** preexisting [virtual table] for the module.
7589
**
7590
** ^The module name is registered on the [database connection] specified
7591
** by the first parameter.  ^The name of the module is given by the
7592
** second parameter.  ^The third parameter is a pointer to
7593
** the implementation of the [virtual table module].   ^The fourth
7594
** parameter is an arbitrary client data pointer that is passed through
7595
** into the [xCreate] and [xConnect] methods of the virtual table module
7596
** when a new virtual table is be being created or reinitialized.
7597
**
7598
** ^The sqlite3_create_module_v2() interface has a fifth parameter which
7599
** is a pointer to a destructor for the pClientData.  ^SQLite will
7600
** invoke the destructor function (if it is not NULL) when SQLite
7601
** no longer needs the pClientData pointer.  ^The destructor will also
7602
** be invoked if the call to sqlite3_create_module_v2() fails.
7603
** ^The sqlite3_create_module()
7604
** interface is equivalent to sqlite3_create_module_v2() with a NULL
7605
** destructor.
7606
**
7607
** ^If the third parameter (the pointer to the sqlite3_module object) is
7608
** NULL then no new module is created and any existing modules with the
7609
** same name are dropped.
7610
**
7611
** See also: [sqlite3_drop_modules()]
7612
*/
7613
SQLITE_API int sqlite3_create_module(
7614
  sqlite3 *db,               /* SQLite connection to register module with */
7615
  const char *zName,         /* Name of the module */
7616
  const sqlite3_module *p,   /* Methods for the module */
7617
  void *pClientData          /* Client data for xCreate/xConnect */
7618
);
7619
SQLITE_API int sqlite3_create_module_v2(
7620
  sqlite3 *db,               /* SQLite connection to register module with */
7621
  const char *zName,         /* Name of the module */
7622
  const sqlite3_module *p,   /* Methods for the module */
7623
  void *pClientData,         /* Client data for xCreate/xConnect */
7624
  void(*xDestroy)(void*)     /* Module destructor function */
7625
);
7626
7627
/*
7628
** CAPI3REF: Remove Unnecessary Virtual Table Implementations
7629
** METHOD: sqlite3
7630
**
7631
** ^The sqlite3_drop_modules(D,L) interface removes all virtual
7632
** table modules from database connection D except those named on list L.
7633
** The L parameter must be either NULL or a pointer to an array of pointers
7634
** to strings where the array is terminated by a single NULL pointer.
7635
** ^If the L parameter is NULL, then all virtual table modules are removed.
7636
**
7637
** See also: [sqlite3_create_module()]
7638
*/
7639
SQLITE_API int sqlite3_drop_modules(
7640
  sqlite3 *db,                /* Remove modules from this connection */
7641
  const char **azKeep         /* Except, do not remove the ones named here */
7642
);
7643
7644
/*
7645
** CAPI3REF: Virtual Table Instance Object
7646
** KEYWORDS: sqlite3_vtab
7647
**
7648
** Every [virtual table module] implementation uses a subclass
7649
** of this object to describe a particular instance
7650
** of the [virtual table].  Each subclass will
7651
** be tailored to the specific needs of the module implementation.
7652
** The purpose of this superclass is to define certain fields that are
7653
** common to all module implementations.
7654
**
7655
** ^Virtual tables methods can set an error message by assigning a
7656
** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
7657
** take care that any prior string is freed by a call to [sqlite3_free()]
7658
** prior to assigning a new string to zErrMsg.  ^After the error message
7659
** is delivered up to the client application, the string will be automatically
7660
** freed by sqlite3_free() and the zErrMsg field will be zeroed.
7661
*/
7662
struct sqlite3_vtab {
7663
  const sqlite3_module *pModule;  /* The module for this virtual table */
7664
  int nRef;                       /* Number of open cursors */
7665
  char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
7666
  /* Virtual table implementations will typically add additional fields */
7667
};
7668
7669
/*
7670
** CAPI3REF: Virtual Table Cursor Object
7671
** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
7672
**
7673
** Every [virtual table module] implementation uses a subclass of the
7674
** following structure to describe cursors that point into the
7675
** [virtual table] and are used
7676
** to loop through the virtual table.  Cursors are created using the
7677
** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
7678
** by the [sqlite3_module.xClose | xClose] method.  Cursors are used
7679
** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
7680
** of the module.  Each module implementation will define
7681
** the content of a cursor structure to suit its own needs.
7682
**
7683
** This superclass exists in order to define fields of the cursor that
7684
** are common to all implementations.
7685
*/
7686
struct sqlite3_vtab_cursor {
7687
  sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
7688
  /* Virtual table implementations will typically add additional fields */
7689
};
7690
7691
/*
7692
** CAPI3REF: Declare The Schema Of A Virtual Table
7693
**
7694
** ^The [xCreate] and [xConnect] methods of a
7695
** [virtual table module] call this interface
7696
** to declare the format (the names and datatypes of the columns) of
7697
** the virtual tables they implement.
7698
*/
7699
SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
7700
7701
/*
7702
** CAPI3REF: Overload A Function For A Virtual Table
7703
** METHOD: sqlite3
7704
**
7705
** ^(Virtual tables can provide alternative implementations of functions
7706
** using the [xFindFunction] method of the [virtual table module].
7707
** But global versions of those functions
7708
** must exist in order to be overloaded.)^
7709
**
7710
** ^(This API makes sure a global version of a function with a particular
7711
** name and number of parameters exists.  If no such function exists
7712
** before this API is called, a new function is created.)^  ^The implementation
7713
** of the new function always causes an exception to be thrown.  So
7714
** the new function is not good for anything by itself.  Its only
7715
** purpose is to be a placeholder function that can be overloaded
7716
** by a [virtual table].
7717
*/
7718
SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
7719
7720
/*
7721
** CAPI3REF: A Handle To An Open BLOB
7722
** KEYWORDS: {BLOB handle} {BLOB handles}
7723
**
7724
** An instance of this object represents an open BLOB on which
7725
** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
7726
** ^Objects of this type are created by [sqlite3_blob_open()]
7727
** and destroyed by [sqlite3_blob_close()].
7728
** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
7729
** can be used to read or write small subsections of the BLOB.
7730
** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
7731
*/
7732
typedef struct sqlite3_blob sqlite3_blob;
7733
7734
/*
7735
** CAPI3REF: Open A BLOB For Incremental I/O
7736
** METHOD: sqlite3
7737
** CONSTRUCTOR: sqlite3_blob
7738
**
7739
** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
7740
** in row iRow, column zColumn, table zTable in database zDb;
7741
** in other words, the same BLOB that would be selected by:
7742
**
7743
** <pre>
7744
**     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
7745
** </pre>)^
7746
**
7747
** ^(Parameter zDb is not the filename that contains the database, but
7748
** rather the symbolic name of the database. For attached databases, this is
7749
** the name that appears after the AS keyword in the [ATTACH] statement.
7750
** For the main database file, the database name is "main". For TEMP
7751
** tables, the database name is "temp".)^
7752
**
7753
** ^If the flags parameter is non-zero, then the BLOB is opened for read
7754
** and write access. ^If the flags parameter is zero, the BLOB is opened for
7755
** read-only access.
7756
**
7757
** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
7758
** in *ppBlob. Otherwise an [error code] is returned and, unless the error
7759
** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
7760
** the API is not misused, it is always safe to call [sqlite3_blob_close()]
7761
** on *ppBlob after this function it returns.
7762
**
7763
** This function fails with SQLITE_ERROR if any of the following are true:
7764
** <ul>
7765
**   <li> ^(Database zDb does not exist)^,
7766
**   <li> ^(Table zTable does not exist within database zDb)^,
7767
**   <li> ^(Table zTable is a WITHOUT ROWID table)^,
7768
**   <li> ^(Column zColumn does not exist)^,
7769
**   <li> ^(Row iRow is not present in the table)^,
7770
**   <li> ^(The specified column of row iRow contains a value that is not
7771
**         a TEXT or BLOB value)^,
7772
**   <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
7773
**         constraint and the blob is being opened for read/write access)^,
7774
**   <li> ^([foreign key constraints | Foreign key constraints] are enabled,
7775
**         column zColumn is part of a [child key] definition and the blob is
7776
**         being opened for read/write access)^.
7777
** </ul>
7778
**
7779
** ^Unless it returns SQLITE_MISUSE, this function sets the
7780
** [database connection] error code and message accessible via
7781
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
7782
**
7783
** A BLOB referenced by sqlite3_blob_open() may be read using the
7784
** [sqlite3_blob_read()] interface and modified by using
7785
** [sqlite3_blob_write()].  The [BLOB handle] can be moved to a
7786
** different row of the same table using the [sqlite3_blob_reopen()]
7787
** interface.  However, the column, table, or database of a [BLOB handle]
7788
** cannot be changed after the [BLOB handle] is opened.
7789
**
7790
** ^(If the row that a BLOB handle points to is modified by an
7791
** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
7792
** then the BLOB handle is marked as "expired".
7793
** This is true if any column of the row is changed, even a column
7794
** other than the one the BLOB handle is open on.)^
7795
** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
7796
** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
7797
** ^(Changes written into a BLOB prior to the BLOB expiring are not
7798
** rolled back by the expiration of the BLOB.  Such changes will eventually
7799
** commit if the transaction continues to completion.)^
7800
**
7801
** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
7802
** the opened blob.  ^The size of a blob may not be changed by this
7803
** interface.  Use the [UPDATE] SQL command to change the size of a
7804
** blob.
7805
**
7806
** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
7807
** and the built-in [zeroblob] SQL function may be used to create a
7808
** zero-filled blob to read or write using the incremental-blob interface.
7809
**
7810
** To avoid a resource leak, every open [BLOB handle] should eventually
7811
** be released by a call to [sqlite3_blob_close()].
7812
**
7813
** See also: [sqlite3_blob_close()],
7814
** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
7815
** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
7816
*/
7817
SQLITE_API int sqlite3_blob_open(
7818
  sqlite3*,
7819
  const char *zDb,
7820
  const char *zTable,
7821
  const char *zColumn,
7822
  sqlite3_int64 iRow,
7823
  int flags,
7824
  sqlite3_blob **ppBlob
7825
);
7826
7827
/*
7828
** CAPI3REF: Move a BLOB Handle to a New Row
7829
** METHOD: sqlite3_blob
7830
**
7831
** ^This function is used to move an existing [BLOB handle] so that it points
7832
** to a different row of the same database table. ^The new row is identified
7833
** by the rowid value passed as the second argument. Only the row can be
7834
** changed. ^The database, table and column on which the blob handle is open
7835
** remain the same. Moving an existing [BLOB handle] to a new row is
7836
** faster than closing the existing handle and opening a new one.
7837
**
7838
** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
7839
** it must exist and there must be either a blob or text value stored in
7840
** the nominated column.)^ ^If the new row is not present in the table, or if
7841
** it does not contain a blob or text value, or if another error occurs, an
7842
** SQLite error code is returned and the blob handle is considered aborted.
7843
** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
7844
** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
7845
** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
7846
** always returns zero.
7847
**
7848
** ^This function sets the database handle error code and message.
7849
*/
7850
SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
7851
7852
/*
7853
** CAPI3REF: Close A BLOB Handle
7854
** DESTRUCTOR: sqlite3_blob
7855
**
7856
** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
7857
** unconditionally.  Even if this routine returns an error code, the
7858
** handle is still closed.)^
7859
**
7860
** ^If the blob handle being closed was opened for read-write access, and if
7861
** the database is in auto-commit mode and there are no other open read-write
7862
** blob handles or active write statements, the current transaction is
7863
** committed. ^If an error occurs while committing the transaction, an error
7864
** code is returned and the transaction rolled back.
7865
**
7866
** Calling this function with an argument that is not a NULL pointer or an
7867
** open blob handle results in undefined behavior. ^Calling this routine
7868
** with a null pointer (such as would be returned by a failed call to
7869
** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
7870
** is passed a valid open blob handle, the values returned by the
7871
** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
7872
*/
7873
SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
7874
7875
/*
7876
** CAPI3REF: Return The Size Of An Open BLOB
7877
** METHOD: sqlite3_blob
7878
**
7879
** ^Returns the size in bytes of the BLOB accessible via the
7880
** successfully opened [BLOB handle] in its only argument.  ^The
7881
** incremental blob I/O routines can only read or overwriting existing
7882
** blob content; they cannot change the size of a blob.
7883
**
7884
** This routine only works on a [BLOB handle] which has been created
7885
** by a prior successful call to [sqlite3_blob_open()] and which has not
7886
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
7887
** to this routine results in undefined and probably undesirable behavior.
7888
*/
7889
SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
7890
7891
/*
7892
** CAPI3REF: Read Data From A BLOB Incrementally
7893
** METHOD: sqlite3_blob
7894
**
7895
** ^(This function is used to read data from an open [BLOB handle] into a
7896
** caller-supplied buffer. N bytes of data are copied into buffer Z
7897
** from the open BLOB, starting at offset iOffset.)^
7898
**
7899
** ^If offset iOffset is less than N bytes from the end of the BLOB,
7900
** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is
7901
** less than zero, [SQLITE_ERROR] is returned and no data is read.
7902
** ^The size of the blob (and hence the maximum value of N+iOffset)
7903
** can be determined using the [sqlite3_blob_bytes()] interface.
7904
**
7905
** ^An attempt to read from an expired [BLOB handle] fails with an
7906
** error code of [SQLITE_ABORT].
7907
**
7908
** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
7909
** Otherwise, an [error code] or an [extended error code] is returned.)^
7910
**
7911
** This routine only works on a [BLOB handle] which has been created
7912
** by a prior successful call to [sqlite3_blob_open()] and which has not
7913
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
7914
** to this routine results in undefined and probably undesirable behavior.
7915
**
7916
** See also: [sqlite3_blob_write()].
7917
*/
7918
SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
7919
7920
/*
7921
** CAPI3REF: Write Data Into A BLOB Incrementally
7922
** METHOD: sqlite3_blob
7923
**
7924
** ^(This function is used to write data into an open [BLOB handle] from a
7925
** caller-supplied buffer. N bytes of data are copied from the buffer Z
7926
** into the open BLOB, starting at offset iOffset.)^
7927
**
7928
** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
7929
** Otherwise, an  [error code] or an [extended error code] is returned.)^
7930
** ^Unless SQLITE_MISUSE is returned, this function sets the
7931
** [database connection] error code and message accessible via
7932
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
7933
**
7934
** ^If the [BLOB handle] passed as the first argument was not opened for
7935
** writing (the flags parameter to [sqlite3_blob_open()] was zero),
7936
** this function returns [SQLITE_READONLY].
7937
**
7938
** This function may only modify the contents of the BLOB; it is
7939
** not possible to increase the size of a BLOB using this API.
7940
** ^If offset iOffset is less than N bytes from the end of the BLOB,
7941
** [SQLITE_ERROR] is returned and no data is written. The size of the
7942
** BLOB (and hence the maximum value of N+iOffset) can be determined
7943
** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
7944
** than zero [SQLITE_ERROR] is returned and no data is written.
7945
**
7946
** ^An attempt to write to an expired [BLOB handle] fails with an
7947
** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
7948
** before the [BLOB handle] expired are not rolled back by the
7949
** expiration of the handle, though of course those changes might
7950
** have been overwritten by the statement that expired the BLOB handle
7951
** or by other independent statements.
7952
**
7953
** This routine only works on a [BLOB handle] which has been created
7954
** by a prior successful call to [sqlite3_blob_open()] and which has not
7955
** been closed by [sqlite3_blob_close()].  Passing any other pointer in
7956
** to this routine results in undefined and probably undesirable behavior.
7957
**
7958
** See also: [sqlite3_blob_read()].
7959
*/
7960
SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
7961
7962
/*
7963
** CAPI3REF: Virtual File System Objects
7964
**
7965
** A virtual filesystem (VFS) is an [sqlite3_vfs] object
7966
** that SQLite uses to interact
7967
** with the underlying operating system.  Most SQLite builds come with a
7968
** single default VFS that is appropriate for the host computer.
7969
** New VFSes can be registered and existing VFSes can be unregistered.
7970
** The following interfaces are provided.
7971
**
7972
** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
7973
** ^Names are case sensitive.
7974
** ^Names are zero-terminated UTF-8 strings.
7975
** ^If there is no match, a NULL pointer is returned.
7976
** ^If zVfsName is NULL then the default VFS is returned.
7977
**
7978
** ^New VFSes are registered with sqlite3_vfs_register().
7979
** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
7980
** ^The same VFS can be registered multiple times without injury.
7981
** ^To make an existing VFS into the default VFS, register it again
7982
** with the makeDflt flag set.  If two different VFSes with the
7983
** same name are registered, the behavior is undefined.  If a
7984
** VFS is registered with a name that is NULL or an empty string,
7985
** then the behavior is undefined.
7986
**
7987
** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
7988
** ^(If the default VFS is unregistered, another VFS is chosen as
7989
** the default.  The choice for the new VFS is arbitrary.)^
7990
*/
7991
SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
7992
SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
7993
SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
7994
7995
/*
7996
** CAPI3REF: Mutexes
7997
**
7998
** The SQLite core uses these routines for thread
7999
** synchronization. Though they are intended for internal
8000
** use by SQLite, code that links against SQLite is
8001
** permitted to use any of these routines.
8002
**
8003
** The SQLite source code contains multiple implementations
8004
** of these mutex routines.  An appropriate implementation
8005
** is selected automatically at compile-time.  The following
8006
** implementations are available in the SQLite core:
8007
**
8008
** <ul>
8009
** <li>   SQLITE_MUTEX_PTHREADS
8010
** <li>   SQLITE_MUTEX_W32
8011
** <li>   SQLITE_MUTEX_NOOP
8012
** </ul>
8013
**
8014
** The SQLITE_MUTEX_NOOP implementation is a set of routines
8015
** that does no real locking and is appropriate for use in
8016
** a single-threaded application.  The SQLITE_MUTEX_PTHREADS and
8017
** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
8018
** and Windows.
8019
**
8020
** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
8021
** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
8022
** implementation is included with the library. In this case the
8023
** application must supply a custom mutex implementation using the
8024
** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
8025
** before calling sqlite3_initialize() or any other public sqlite3_
8026
** function that calls sqlite3_initialize().
8027
**
8028
** ^The sqlite3_mutex_alloc() routine allocates a new
8029
** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
8030
** routine returns NULL if it is unable to allocate the requested
8031
** mutex.  The argument to sqlite3_mutex_alloc() must one of these
8032
** integer constants:
8033
**
8034
** <ul>
8035
** <li>  SQLITE_MUTEX_FAST
8036
** <li>  SQLITE_MUTEX_RECURSIVE
8037
** <li>  SQLITE_MUTEX_STATIC_MAIN
8038
** <li>  SQLITE_MUTEX_STATIC_MEM
8039
** <li>  SQLITE_MUTEX_STATIC_OPEN
8040
** <li>  SQLITE_MUTEX_STATIC_PRNG
8041
** <li>  SQLITE_MUTEX_STATIC_LRU
8042
** <li>  SQLITE_MUTEX_STATIC_PMEM
8043
** <li>  SQLITE_MUTEX_STATIC_APP1
8044
** <li>  SQLITE_MUTEX_STATIC_APP2
8045
** <li>  SQLITE_MUTEX_STATIC_APP3
8046
** <li>  SQLITE_MUTEX_STATIC_VFS1
8047
** <li>  SQLITE_MUTEX_STATIC_VFS2
8048
** <li>  SQLITE_MUTEX_STATIC_VFS3
8049
** </ul>
8050
**
8051
** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
8052
** cause sqlite3_mutex_alloc() to create
8053
** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
8054
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
8055
** The mutex implementation does not need to make a distinction
8056
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
8057
** not want to.  SQLite will only request a recursive mutex in
8058
** cases where it really needs one.  If a faster non-recursive mutex
8059
** implementation is available on the host platform, the mutex subsystem
8060
** might return such a mutex in response to SQLITE_MUTEX_FAST.
8061
**
8062
** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
8063
** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
8064
** a pointer to a static preexisting mutex.  ^Nine static mutexes are
8065
** used by the current version of SQLite.  Future versions of SQLite
8066
** may add additional static mutexes.  Static mutexes are for internal
8067
** use by SQLite only.  Applications that use SQLite mutexes should
8068
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
8069
** SQLITE_MUTEX_RECURSIVE.
8070
**
8071
** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
8072
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
8073
** returns a different mutex on every call.  ^For the static
8074
** mutex types, the same mutex is returned on every call that has
8075
** the same type number.
8076
**
8077
** ^The sqlite3_mutex_free() routine deallocates a previously
8078
** allocated dynamic mutex.  Attempting to deallocate a static
8079
** mutex results in undefined behavior.
8080
**
8081
** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
8082
** to enter a mutex.  ^If another thread is already within the mutex,
8083
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
8084
** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
8085
** upon successful entry.  ^(Mutexes created using
8086
** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
8087
** In such cases, the
8088
** mutex must be exited an equal number of times before another thread
8089
** can enter.)^  If the same thread tries to enter any mutex other
8090
** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
8091
**
8092
** ^(Some systems (for example, Windows 95) do not support the operation
8093
** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
8094
** will always return SQLITE_BUSY. In most cases the SQLite core only uses
8095
** sqlite3_mutex_try() as an optimization, so this is acceptable
8096
** behavior. The exceptions are unix builds that set the
8097
** SQLITE_ENABLE_SETLK_TIMEOUT build option. In that case a working
8098
** sqlite3_mutex_try() is required.)^
8099
**
8100
** ^The sqlite3_mutex_leave() routine exits a mutex that was
8101
** previously entered by the same thread.   The behavior
8102
** is undefined if the mutex is not currently entered by the
8103
** calling thread or is not currently allocated.
8104
**
8105
** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(),
8106
** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer,
8107
** then any of the four routines behaves as a no-op.
8108
**
8109
** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
8110
*/
8111
SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
8112
SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
8113
SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
8114
SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
8115
SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
8116
8117
/*
8118
** CAPI3REF: Mutex Methods Object
8119
**
8120
** An instance of this structure defines the low-level routines
8121
** used to allocate and use mutexes.
8122
**
8123
** Usually, the default mutex implementations provided by SQLite are
8124
** sufficient, however the application has the option of substituting a custom
8125
** implementation for specialized deployments or systems for which SQLite
8126
** does not provide a suitable implementation. In this case, the application
8127
** creates and populates an instance of this structure to pass
8128
** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
8129
** Additionally, an instance of this structure can be used as an
8130
** output variable when querying the system for the current mutex
8131
** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
8132
**
8133
** ^The xMutexInit method defined by this structure is invoked as
8134
** part of system initialization by the sqlite3_initialize() function.
8135
** ^The xMutexInit routine is called by SQLite exactly once for each
8136
** effective call to [sqlite3_initialize()].
8137
**
8138
** ^The xMutexEnd method defined by this structure is invoked as
8139
** part of system shutdown by the sqlite3_shutdown() function. The
8140
** implementation of this method is expected to release all outstanding
8141
** resources obtained by the mutex methods implementation, especially
8142
** those obtained by the xMutexInit method.  ^The xMutexEnd()
8143
** interface is invoked exactly once for each call to [sqlite3_shutdown()].
8144
**
8145
** ^(The remaining seven methods defined by this structure (xMutexAlloc,
8146
** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
8147
** xMutexNotheld) implement the following interfaces (respectively):
8148
**
8149
** <ul>
8150
**   <li>  [sqlite3_mutex_alloc()] </li>
8151
**   <li>  [sqlite3_mutex_free()] </li>
8152
**   <li>  [sqlite3_mutex_enter()] </li>
8153
**   <li>  [sqlite3_mutex_try()] </li>
8154
**   <li>  [sqlite3_mutex_leave()] </li>
8155
**   <li>  [sqlite3_mutex_held()] </li>
8156
**   <li>  [sqlite3_mutex_notheld()] </li>
8157
** </ul>)^
8158
**
8159
** The only difference is that the public sqlite3_XXX functions enumerated
8160
** above silently ignore any invocations that pass a NULL pointer instead
8161
** of a valid mutex handle. The implementations of the methods defined
8162
** by this structure are not required to handle this case. The results
8163
** of passing a NULL pointer instead of a valid mutex handle are undefined
8164
** (i.e. it is acceptable to provide an implementation that segfaults if
8165
** it is passed a NULL pointer).
8166
**
8167
** The xMutexInit() method must be threadsafe.  It must be harmless to
8168
** invoke xMutexInit() multiple times within the same process and without
8169
** intervening calls to xMutexEnd().  Second and subsequent calls to
8170
** xMutexInit() must be no-ops.
8171
**
8172
** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
8173
** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
8174
** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
8175
** memory allocation for a fast or recursive mutex.
8176
**
8177
** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
8178
** called, but only if the prior call to xMutexInit returned SQLITE_OK.
8179
** If xMutexInit fails in any way, it is expected to clean up after itself
8180
** prior to returning.
8181
*/
8182
typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
8183
struct sqlite3_mutex_methods {
8184
  int (*xMutexInit)(void);
8185
  int (*xMutexEnd)(void);
8186
  sqlite3_mutex *(*xMutexAlloc)(int);
8187
  void (*xMutexFree)(sqlite3_mutex *);
8188
  void (*xMutexEnter)(sqlite3_mutex *);
8189
  int (*xMutexTry)(sqlite3_mutex *);
8190
  void (*xMutexLeave)(sqlite3_mutex *);
8191
  int (*xMutexHeld)(sqlite3_mutex *);
8192
  int (*xMutexNotheld)(sqlite3_mutex *);
8193
};
8194
8195
/*
8196
** CAPI3REF: Mutex Verification Routines
8197
**
8198
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
8199
** are intended for use inside assert() statements.  The SQLite core
8200
** never uses these routines except inside an assert() and applications
8201
** are advised to follow the lead of the core.  The SQLite core only
8202
** provides implementations for these routines when it is compiled
8203
** with the SQLITE_DEBUG flag.  External mutex implementations
8204
** are only required to provide these routines if SQLITE_DEBUG is
8205
** defined and if NDEBUG is not defined.
8206
**
8207
** These routines should return true if the mutex in their argument
8208
** is held or not held, respectively, by the calling thread.
8209
**
8210
** The implementation is not required to provide versions of these
8211
** routines that actually work. If the implementation does not provide working
8212
** versions of these routines, it should at least provide stubs that always
8213
** return true so that one does not get spurious assertion failures.
8214
**
8215
** If the argument to sqlite3_mutex_held() is a NULL pointer then
8216
** the routine should return 1.   This seems counter-intuitive since
8217
** clearly the mutex cannot be held if it does not exist.  But
8218
** the reason the mutex does not exist is because the build is not
8219
** using mutexes.  And we do not want the assert() containing the
8220
** call to sqlite3_mutex_held() to fail, so a non-zero return is
8221
** the appropriate thing to do.  The sqlite3_mutex_notheld()
8222
** interface should also return 1 when given a NULL pointer.
8223
*/
8224
#ifndef NDEBUG
8225
SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
8226
SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
8227
#endif
8228
8229
/*
8230
** CAPI3REF: Mutex Types
8231
**
8232
** The [sqlite3_mutex_alloc()] interface takes a single argument
8233
** which is one of these integer constants.
8234
**
8235
** The set of static mutexes may change from one SQLite release to the
8236
** next.  Applications that override the built-in mutex logic must be
8237
** prepared to accommodate additional static mutexes.
8238
*/
8239
#define SQLITE_MUTEX_FAST             0
8240
#define SQLITE_MUTEX_RECURSIVE        1
8241
#define SQLITE_MUTEX_STATIC_MAIN      2
8242
#define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
8243
#define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
8244
#define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
8245
#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_randomness() */
8246
#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
8247
#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
8248
#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
8249
#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
8250
#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
8251
#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */
8252
#define SQLITE_MUTEX_STATIC_VFS1     11  /* For use by built-in VFS */
8253
#define SQLITE_MUTEX_STATIC_VFS2     12  /* For use by extension VFS */
8254
#define SQLITE_MUTEX_STATIC_VFS3     13  /* For use by application VFS */
8255
8256
/* Legacy compatibility: */
8257
#define SQLITE_MUTEX_STATIC_MASTER    2
8258
8259
8260
/*
8261
** CAPI3REF: Retrieve the mutex for a database connection
8262
** METHOD: sqlite3
8263
**
8264
** ^This interface returns a pointer the [sqlite3_mutex] object that
8265
** serializes access to the [database connection] given in the argument
8266
** when the [threading mode] is Serialized.
8267
** ^If the [threading mode] is Single-thread or Multi-thread then this
8268
** routine returns a NULL pointer.
8269
*/
8270
SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
8271
8272
/*
8273
** CAPI3REF: Low-Level Control Of Database Files
8274
** METHOD: sqlite3
8275
** KEYWORDS: {file control}
8276
**
8277
** ^The [sqlite3_file_control()] interface makes a direct call to the
8278
** xFileControl method for the [sqlite3_io_methods] object associated
8279
** with a particular database identified by the second argument. ^The
8280
** name of the database is "main" for the main database or "temp" for the
8281
** TEMP database, or the name that appears after the AS keyword for
8282
** databases that are added using the [ATTACH] SQL command.
8283
** ^A NULL pointer can be used in place of "main" to refer to the
8284
** main database file.
8285
** ^The third and fourth parameters to this routine
8286
** are passed directly through to the second and third parameters of
8287
** the xFileControl method.  ^The return value of the xFileControl
8288
** method becomes the return value of this routine.
8289
**
8290
** A few opcodes for [sqlite3_file_control()] are handled directly
8291
** by the SQLite core and never invoke the
8292
** sqlite3_io_methods.xFileControl method.
8293
** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes
8294
** a pointer to the underlying [sqlite3_file] object to be written into
8295
** the space pointed to by the 4th parameter.  The
8296
** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns
8297
** the [sqlite3_file] object associated with the journal file instead of
8298
** the main database.  The [SQLITE_FCNTL_VFS_POINTER] opcode returns
8299
** a pointer to the underlying [sqlite3_vfs] object for the file.
8300
** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter
8301
** from the pager.
8302
**
8303
** ^If the second parameter (zDbName) does not match the name of any
8304
** open database file, then SQLITE_ERROR is returned.  ^This error
8305
** code is not remembered and will not be recalled by [sqlite3_errcode()]
8306
** or [sqlite3_errmsg()].  The underlying xFileControl method might
8307
** also return SQLITE_ERROR.  There is no way to distinguish between
8308
** an incorrect zDbName and an SQLITE_ERROR return from the underlying
8309
** xFileControl method.
8310
**
8311
** See also: [file control opcodes]
8312
*/
8313
SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
8314
8315
/*
8316
** CAPI3REF: Testing Interface
8317
**
8318
** ^The sqlite3_test_control() interface is used to read out internal
8319
** state of SQLite and to inject faults into SQLite for testing
8320
** purposes.  ^The first parameter is an operation code that determines
8321
** the number, meaning, and operation of all subsequent parameters.
8322
**
8323
** This interface is not for use by applications.  It exists solely
8324
** for verifying the correct operation of the SQLite library.  Depending
8325
** on how the SQLite library is compiled, this interface might not exist.
8326
**
8327
** The details of the operation codes, their meanings, the parameters
8328
** they take, and what they do are all subject to change without notice.
8329
** Unlike most of the SQLite API, this function is not guaranteed to
8330
** operate consistently from one release to the next.
8331
*/
8332
SQLITE_API int sqlite3_test_control(int op, ...);
8333
8334
/*
8335
** CAPI3REF: Testing Interface Operation Codes
8336
**
8337
** These constants are the valid operation code parameters used
8338
** as the first argument to [sqlite3_test_control()].
8339
**
8340
** These parameters and their meanings are subject to change
8341
** without notice.  These values are for testing purposes only.
8342
** Applications should not use any of these parameters or the
8343
** [sqlite3_test_control()] interface.
8344
*/
8345
#define SQLITE_TESTCTRL_FIRST                    5
8346
#define SQLITE_TESTCTRL_PRNG_SAVE                5
8347
#define SQLITE_TESTCTRL_PRNG_RESTORE             6
8348
#define SQLITE_TESTCTRL_PRNG_RESET               7  /* NOT USED */
8349
#define SQLITE_TESTCTRL_FK_NO_ACTION             7
8350
#define SQLITE_TESTCTRL_BITVEC_TEST              8
8351
#define SQLITE_TESTCTRL_FAULT_INSTALL            9
8352
#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
8353
#define SQLITE_TESTCTRL_PENDING_BYTE            11
8354
#define SQLITE_TESTCTRL_ASSERT                  12
8355
#define SQLITE_TESTCTRL_ALWAYS                  13
8356
#define SQLITE_TESTCTRL_RESERVE                 14  /* NOT USED */
8357
#define SQLITE_TESTCTRL_JSON_SELFCHECK          14
8358
#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
8359
#define SQLITE_TESTCTRL_ISKEYWORD               16  /* NOT USED */
8360
#define SQLITE_TESTCTRL_GETOPT                  16
8361
#define SQLITE_TESTCTRL_SCRATCHMALLOC           17  /* NOT USED */
8362
#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS      17
8363
#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
8364
#define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
8365
#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD    19
8366
#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
8367
#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
8368
#define SQLITE_TESTCTRL_BYTEORDER               22
8369
#define SQLITE_TESTCTRL_ISINIT                  23
8370
#define SQLITE_TESTCTRL_SORTER_MMAP             24
8371
#define SQLITE_TESTCTRL_IMPOSTER                25
8372
#define SQLITE_TESTCTRL_PARSER_COVERAGE         26
8373
#define SQLITE_TESTCTRL_RESULT_INTREAL          27
8374
#define SQLITE_TESTCTRL_PRNG_SEED               28
8375
#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS     29
8376
#define SQLITE_TESTCTRL_SEEK_COUNT              30
8377
#define SQLITE_TESTCTRL_TRACEFLAGS              31
8378
#define SQLITE_TESTCTRL_TUNE                    32
8379
#define SQLITE_TESTCTRL_LOGEST                  33
8380
#define SQLITE_TESTCTRL_USELONGDOUBLE           34  /* NOT USED */
8381
#define SQLITE_TESTCTRL_LAST                    34  /* Largest TESTCTRL */
8382
8383
/*
8384
** CAPI3REF: SQL Keyword Checking
8385
**
8386
** These routines provide access to the set of SQL language keywords
8387
** recognized by SQLite.  Applications can uses these routines to determine
8388
** whether or not a specific identifier needs to be escaped (for example,
8389
** by enclosing in double-quotes) so as not to confuse the parser.
8390
**
8391
** The sqlite3_keyword_count() interface returns the number of distinct
8392
** keywords understood by SQLite.
8393
**
8394
** The sqlite3_keyword_name(N,Z,L) interface finds the 0-based N-th keyword and
8395
** makes *Z point to that keyword expressed as UTF8 and writes the number
8396
** of bytes in the keyword into *L.  The string that *Z points to is not
8397
** zero-terminated.  The sqlite3_keyword_name(N,Z,L) routine returns
8398
** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
8399
** or L are NULL or invalid pointers then calls to
8400
** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
8401
**
8402
** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
8403
** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
8404
** if it is and zero if not.
8405
**
8406
** The parser used by SQLite is forgiving.  It is often possible to use
8407
** a keyword as an identifier as long as such use does not result in a
8408
** parsing ambiguity.  For example, the statement
8409
** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
8410
** creates a new table named "BEGIN" with three columns named
8411
** "REPLACE", "PRAGMA", and "END".  Nevertheless, best practice is to avoid
8412
** using keywords as identifiers.  Common techniques used to avoid keyword
8413
** name collisions include:
8414
** <ul>
8415
** <li> Put all identifier names inside double-quotes.  This is the official
8416
**      SQL way to escape identifier names.
8417
** <li> Put identifier names inside &#91;...&#93;.  This is not standard SQL,
8418
**      but it is what SQL Server does and so lots of programmers use this
8419
**      technique.
8420
** <li> Begin every identifier with the letter "Z" as no SQL keywords start
8421
**      with "Z".
8422
** <li> Include a digit somewhere in every identifier name.
8423
** </ul>
8424
**
8425
** Note that the number of keywords understood by SQLite can depend on
8426
** compile-time options.  For example, "VACUUM" is not a keyword if
8427
** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option.  Also,
8428
** new keywords may be added to future releases of SQLite.
8429
*/
8430
SQLITE_API int sqlite3_keyword_count(void);
8431
SQLITE_API int sqlite3_keyword_name(int,const char**,int*);
8432
SQLITE_API int sqlite3_keyword_check(const char*,int);
8433
8434
/*
8435
** CAPI3REF: Dynamic String Object
8436
** KEYWORDS: {dynamic string}
8437
**
8438
** An instance of the sqlite3_str object contains a dynamically-sized
8439
** string under construction.
8440
**
8441
** The lifecycle of an sqlite3_str object is as follows:
8442
** <ol>
8443
** <li> ^The sqlite3_str object is created using [sqlite3_str_new()].
8444
** <li> ^Text is appended to the sqlite3_str object using various
8445
** methods, such as [sqlite3_str_appendf()].
8446
** <li> ^The sqlite3_str object is destroyed and the string it created
8447
** is returned using the [sqlite3_str_finish()] interface.
8448
** </ol>
8449
*/
8450
typedef struct sqlite3_str sqlite3_str;
8451
8452
/*
8453
** CAPI3REF: Create A New Dynamic String Object
8454
** CONSTRUCTOR: sqlite3_str
8455
**
8456
** ^The [sqlite3_str_new(D)] interface allocates and initializes
8457
** a new [sqlite3_str] object.  To avoid memory leaks, the object returned by
8458
** [sqlite3_str_new()] must be freed by a subsequent call to
8459
** [sqlite3_str_finish(X)].
8460
**
8461
** ^The [sqlite3_str_new(D)] interface always returns a pointer to a
8462
** valid [sqlite3_str] object, though in the event of an out-of-memory
8463
** error the returned object might be a special singleton that will
8464
** silently reject new text, always return SQLITE_NOMEM from
8465
** [sqlite3_str_errcode()], always return 0 for
8466
** [sqlite3_str_length()], and always return NULL from
8467
** [sqlite3_str_finish(X)].  It is always safe to use the value
8468
** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter
8469
** to any of the other [sqlite3_str] methods.
8470
**
8471
** The D parameter to [sqlite3_str_new(D)] may be NULL.  If the
8472
** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum
8473
** length of the string contained in the [sqlite3_str] object will be
8474
** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead
8475
** of [SQLITE_MAX_LENGTH].
8476
*/
8477
SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*);
8478
8479
/*
8480
** CAPI3REF: Finalize A Dynamic String
8481
** DESTRUCTOR: sqlite3_str
8482
**
8483
** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X
8484
** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()]
8485
** that contains the constructed string.  The calling application should
8486
** pass the returned value to [sqlite3_free()] to avoid a memory leak.
8487
** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any
8488
** errors were encountered during construction of the string.  ^The
8489
** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the
8490
** string in [sqlite3_str] object X is zero bytes long.
8491
*/
8492
SQLITE_API char *sqlite3_str_finish(sqlite3_str*);
8493
8494
/*
8495
** CAPI3REF: Add Content To A Dynamic String
8496
** METHOD: sqlite3_str
8497
**
8498
** These interfaces add content to an sqlite3_str object previously obtained
8499
** from [sqlite3_str_new()].
8500
**
8501
** ^The [sqlite3_str_appendf(X,F,...)] and
8502
** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf]
8503
** functionality of SQLite to append formatted text onto the end of
8504
** [sqlite3_str] object X.
8505
**
8506
** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S
8507
** onto the end of the [sqlite3_str] object X.  N must be non-negative.
8508
** S must contain at least N non-zero bytes of content.  To append a
8509
** zero-terminated string in its entirety, use the [sqlite3_str_appendall()]
8510
** method instead.
8511
**
8512
** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of
8513
** zero-terminated string S onto the end of [sqlite3_str] object X.
8514
**
8515
** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the
8516
** single-byte character C onto the end of [sqlite3_str] object X.
8517
** ^This method can be used, for example, to add whitespace indentation.
8518
**
8519
** ^The [sqlite3_str_reset(X)] method resets the string under construction
8520
** inside [sqlite3_str] object X back to zero bytes in length.
8521
**
8522
** These methods do not return a result code.  ^If an error occurs, that fact
8523
** is recorded in the [sqlite3_str] object and can be recovered by a
8524
** subsequent call to [sqlite3_str_errcode(X)].
8525
*/
8526
SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...);
8527
SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list);
8528
SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N);
8529
SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn);
8530
SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C);
8531
SQLITE_API void sqlite3_str_reset(sqlite3_str*);
8532
8533
/*
8534
** CAPI3REF: Status Of A Dynamic String
8535
** METHOD: sqlite3_str
8536
**
8537
** These interfaces return the current status of an [sqlite3_str] object.
8538
**
8539
** ^If any prior errors have occurred while constructing the dynamic string
8540
** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return
8541
** an appropriate error code.  ^The [sqlite3_str_errcode(X)] method returns
8542
** [SQLITE_NOMEM] following any out-of-memory error, or
8543
** [SQLITE_TOOBIG] if the size of the dynamic string exceeds
8544
** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors.
8545
**
8546
** ^The [sqlite3_str_length(X)] method returns the current length, in bytes,
8547
** of the dynamic string under construction in [sqlite3_str] object X.
8548
** ^The length returned by [sqlite3_str_length(X)] does not include the
8549
** zero-termination byte.
8550
**
8551
** ^The [sqlite3_str_value(X)] method returns a pointer to the current
8552
** content of the dynamic string under construction in X.  The value
8553
** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X
8554
** and might be freed or altered by any subsequent method on the same
8555
** [sqlite3_str] object.  Applications must not used the pointer returned
8556
** [sqlite3_str_value(X)] after any subsequent method call on the same
8557
** object.  ^Applications may change the content of the string returned
8558
** by [sqlite3_str_value(X)] as long as they do not write into any bytes
8559
** outside the range of 0 to [sqlite3_str_length(X)] and do not read or
8560
** write any byte after any subsequent sqlite3_str method call.
8561
*/
8562
SQLITE_API int sqlite3_str_errcode(sqlite3_str*);
8563
SQLITE_API int sqlite3_str_length(sqlite3_str*);
8564
SQLITE_API char *sqlite3_str_value(sqlite3_str*);
8565
8566
/*
8567
** CAPI3REF: SQLite Runtime Status
8568
**
8569
** ^These interfaces are used to retrieve runtime status information
8570
** about the performance of SQLite, and optionally to reset various
8571
** highwater marks.  ^The first argument is an integer code for
8572
** the specific parameter to measure.  ^(Recognized integer codes
8573
** are of the form [status parameters | SQLITE_STATUS_...].)^
8574
** ^The current value of the parameter is returned into *pCurrent.
8575
** ^The highest recorded value is returned in *pHighwater.  ^If the
8576
** resetFlag is true, then the highest record value is reset after
8577
** *pHighwater is written.  ^(Some parameters do not record the highest
8578
** value.  For those parameters
8579
** nothing is written into *pHighwater and the resetFlag is ignored.)^
8580
** ^(Other parameters record only the highwater mark and not the current
8581
** value.  For these latter parameters nothing is written into *pCurrent.)^
8582
**
8583
** ^The sqlite3_status() and sqlite3_status64() routines return
8584
** SQLITE_OK on success and a non-zero [error code] on failure.
8585
**
8586
** If either the current value or the highwater mark is too large to
8587
** be represented by a 32-bit integer, then the values returned by
8588
** sqlite3_status() are undefined.
8589
**
8590
** See also: [sqlite3_db_status()]
8591
*/
8592
SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
8593
SQLITE_API int sqlite3_status64(
8594
  int op,
8595
  sqlite3_int64 *pCurrent,
8596
  sqlite3_int64 *pHighwater,
8597
  int resetFlag
8598
);
8599
8600
8601
/*
8602
** CAPI3REF: Status Parameters
8603
** KEYWORDS: {status parameters}
8604
**
8605
** These integer constants designate various run-time status parameters
8606
** that can be returned by [sqlite3_status()].
8607
**
8608
** <dl>
8609
** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
8610
** <dd>This parameter is the current amount of memory checked out
8611
** using [sqlite3_malloc()], either directly or indirectly.  The
8612
** figure includes calls made to [sqlite3_malloc()] by the application
8613
** and internal memory usage by the SQLite library.  Auxiliary page-cache
8614
** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
8615
** this parameter.  The amount returned is the sum of the allocation
8616
** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
8617
**
8618
** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
8619
** <dd>This parameter records the largest memory allocation request
8620
** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
8621
** internal equivalents).  Only the value returned in the
8622
** *pHighwater parameter to [sqlite3_status()] is of interest.
8623
** The value written into the *pCurrent parameter is undefined.</dd>)^
8624
**
8625
** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
8626
** <dd>This parameter records the number of separate memory allocations
8627
** currently checked out.</dd>)^
8628
**
8629
** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
8630
** <dd>This parameter returns the number of pages used out of the
8631
** [pagecache memory allocator] that was configured using
8632
** [SQLITE_CONFIG_PAGECACHE].  The
8633
** value returned is in pages, not in bytes.</dd>)^
8634
**
8635
** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
8636
** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
8637
** <dd>This parameter returns the number of bytes of page cache
8638
** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
8639
** buffer and where forced to overflow to [sqlite3_malloc()].  The
8640
** returned value includes allocations that overflowed because they
8641
** where too large (they were larger than the "sz" parameter to
8642
** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
8643
** no space was left in the page cache.</dd>)^
8644
**
8645
** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
8646
** <dd>This parameter records the largest memory allocation request
8647
** handed to the [pagecache memory allocator].  Only the value returned in the
8648
** *pHighwater parameter to [sqlite3_status()] is of interest.
8649
** The value written into the *pCurrent parameter is undefined.</dd>)^
8650
**
8651
** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt>
8652
** <dd>No longer used.</dd>
8653
**
8654
** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
8655
** <dd>No longer used.</dd>
8656
**
8657
** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
8658
** <dd>No longer used.</dd>
8659
**
8660
** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
8661
** <dd>The *pHighwater parameter records the deepest parser stack.
8662
** The *pCurrent value is undefined.  The *pHighwater value is only
8663
** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
8664
** </dl>
8665
**
8666
** New status parameters may be added from time to time.
8667
*/
8668
#define SQLITE_STATUS_MEMORY_USED          0
8669
#define SQLITE_STATUS_PAGECACHE_USED       1
8670
#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
8671
#define SQLITE_STATUS_SCRATCH_USED         3  /* NOT USED */
8672
#define SQLITE_STATUS_SCRATCH_OVERFLOW     4  /* NOT USED */
8673
#define SQLITE_STATUS_MALLOC_SIZE          5
8674
#define SQLITE_STATUS_PARSER_STACK         6
8675
#define SQLITE_STATUS_PAGECACHE_SIZE       7
8676
#define SQLITE_STATUS_SCRATCH_SIZE         8  /* NOT USED */
8677
#define SQLITE_STATUS_MALLOC_COUNT         9
8678
8679
/*
8680
** CAPI3REF: Database Connection Status
8681
** METHOD: sqlite3
8682
**
8683
** ^This interface is used to retrieve runtime status information
8684
** about a single [database connection].  ^The first argument is the
8685
** database connection object to be interrogated.  ^The second argument
8686
** is an integer constant, taken from the set of
8687
** [SQLITE_DBSTATUS options], that
8688
** determines the parameter to interrogate.  The set of
8689
** [SQLITE_DBSTATUS options] is likely
8690
** to grow in future releases of SQLite.
8691
**
8692
** ^The current value of the requested parameter is written into *pCur
8693
** and the highest instantaneous value is written into *pHiwtr.  ^If
8694
** the resetFlg is true, then the highest instantaneous value is
8695
** reset back down to the current value.
8696
**
8697
** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
8698
** non-zero [error code] on failure.
8699
**
8700
** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
8701
*/
8702
SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
8703
8704
/*
8705
** CAPI3REF: Status Parameters for database connections
8706
** KEYWORDS: {SQLITE_DBSTATUS options}
8707
**
8708
** These constants are the available integer "verbs" that can be passed as
8709
** the second argument to the [sqlite3_db_status()] interface.
8710
**
8711
** New verbs may be added in future releases of SQLite. Existing verbs
8712
** might be discontinued. Applications should check the return code from
8713
** [sqlite3_db_status()] to make sure that the call worked.
8714
** The [sqlite3_db_status()] interface will return a non-zero error code
8715
** if a discontinued or unsupported verb is invoked.
8716
**
8717
** <dl>
8718
** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
8719
** <dd>This parameter returns the number of lookaside memory slots currently
8720
** checked out.</dd>)^
8721
**
8722
** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
8723
** <dd>This parameter returns the number of malloc attempts that were
8724
** satisfied using lookaside memory. Only the high-water value is meaningful;
8725
** the current value is always zero.)^
8726
**
8727
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
8728
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
8729
** <dd>This parameter returns the number malloc attempts that might have
8730
** been satisfied using lookaside memory but failed due to the amount of
8731
** memory requested being larger than the lookaside slot size.
8732
** Only the high-water value is meaningful;
8733
** the current value is always zero.)^
8734
**
8735
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
8736
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
8737
** <dd>This parameter returns the number malloc attempts that might have
8738
** been satisfied using lookaside memory but failed due to all lookaside
8739
** memory already being in use.
8740
** Only the high-water value is meaningful;
8741
** the current value is always zero.)^
8742
**
8743
** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
8744
** <dd>This parameter returns the approximate number of bytes of heap
8745
** memory used by all pager caches associated with the database connection.)^
8746
** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
8747
**
8748
** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
8749
** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
8750
** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
8751
** pager cache is shared between two or more connections the bytes of heap
8752
** memory used by that pager cache is divided evenly between the attached
8753
** connections.)^  In other words, if none of the pager caches associated
8754
** with the database connection are shared, this request returns the same
8755
** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are
8756
** shared, the value returned by this call will be smaller than that returned
8757
** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
8758
** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
8759
**
8760
** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
8761
** <dd>This parameter returns the approximate number of bytes of heap
8762
** memory used to store the schema for all databases associated
8763
** with the connection - main, temp, and any [ATTACH]-ed databases.)^
8764
** ^The full amount of memory used by the schemas is reported, even if the
8765
** schema memory is shared with other database connections due to
8766
** [shared cache mode] being enabled.
8767
** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
8768
**
8769
** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
8770
** <dd>This parameter returns the approximate number of bytes of heap
8771
** and lookaside memory used by all prepared statements associated with
8772
** the database connection.)^
8773
** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
8774
** </dd>
8775
**
8776
** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
8777
** <dd>This parameter returns the number of pager cache hits that have
8778
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
8779
** is always 0.
8780
** </dd>
8781
**
8782
** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
8783
** <dd>This parameter returns the number of pager cache misses that have
8784
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
8785
** is always 0.
8786
** </dd>
8787
**
8788
** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
8789
** <dd>This parameter returns the number of dirty cache entries that have
8790
** been written to disk. Specifically, the number of pages written to the
8791
** wal file in wal mode databases, or the number of pages written to the
8792
** database file in rollback mode databases. Any pages written as part of
8793
** transaction rollback or database recovery operations are not included.
8794
** If an IO or other error occurs while writing a page to disk, the effect
8795
** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
8796
** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
8797
** </dd>
8798
**
8799
** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt>
8800
** <dd>This parameter returns the number of dirty cache entries that have
8801
** been written to disk in the middle of a transaction due to the page
8802
** cache overflowing. Transactions are more efficient if they are written
8803
** to disk all at once. When pages spill mid-transaction, that introduces
8804
** additional overhead. This parameter can be used help identify
8805
** inefficiencies that can be resolved by increasing the cache size.
8806
** </dd>
8807
**
8808
** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
8809
** <dd>This parameter returns zero for the current value if and only if
8810
** all foreign key constraints (deferred or immediate) have been
8811
** resolved.)^  ^The highwater mark is always 0.
8812
** </dd>
8813
** </dl>
8814
*/
8815
#define SQLITE_DBSTATUS_LOOKASIDE_USED       0
8816
#define SQLITE_DBSTATUS_CACHE_USED           1
8817
#define SQLITE_DBSTATUS_SCHEMA_USED          2
8818
#define SQLITE_DBSTATUS_STMT_USED            3
8819
#define SQLITE_DBSTATUS_LOOKASIDE_HIT        4
8820
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE  5
8821
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL  6
8822
#define SQLITE_DBSTATUS_CACHE_HIT            7
8823
#define SQLITE_DBSTATUS_CACHE_MISS           8
8824
#define SQLITE_DBSTATUS_CACHE_WRITE          9
8825
#define SQLITE_DBSTATUS_DEFERRED_FKS        10
8826
#define SQLITE_DBSTATUS_CACHE_USED_SHARED   11
8827
#define SQLITE_DBSTATUS_CACHE_SPILL         12
8828
#define SQLITE_DBSTATUS_MAX                 12   /* Largest defined DBSTATUS */
8829
8830
8831
/*
8832
** CAPI3REF: Prepared Statement Status
8833
** METHOD: sqlite3_stmt
8834
**
8835
** ^(Each prepared statement maintains various
8836
** [SQLITE_STMTSTATUS counters] that measure the number
8837
** of times it has performed specific operations.)^  These counters can
8838
** be used to monitor the performance characteristics of the prepared
8839
** statements.  For example, if the number of table steps greatly exceeds
8840
** the number of table searches or result rows, that would tend to indicate
8841
** that the prepared statement is using a full table scan rather than
8842
** an index.
8843
**
8844
** ^(This interface is used to retrieve and reset counter values from
8845
** a [prepared statement].  The first argument is the prepared statement
8846
** object to be interrogated.  The second argument
8847
** is an integer code for a specific [SQLITE_STMTSTATUS counter]
8848
** to be interrogated.)^
8849
** ^The current value of the requested counter is returned.
8850
** ^If the resetFlg is true, then the counter is reset to zero after this
8851
** interface call returns.
8852
**
8853
** See also: [sqlite3_status()] and [sqlite3_db_status()].
8854
*/
8855
SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
8856
8857
/*
8858
** CAPI3REF: Status Parameters for prepared statements
8859
** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
8860
**
8861
** These preprocessor macros define integer codes that name counter
8862
** values associated with the [sqlite3_stmt_status()] interface.
8863
** The meanings of the various counters are as follows:
8864
**
8865
** <dl>
8866
** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
8867
** <dd>^This is the number of times that SQLite has stepped forward in
8868
** a table as part of a full table scan.  Large numbers for this counter
8869
** may indicate opportunities for performance improvement through
8870
** careful use of indices.</dd>
8871
**
8872
** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
8873
** <dd>^This is the number of sort operations that have occurred.
8874
** A non-zero value in this counter may indicate an opportunity to
8875
** improvement performance through careful use of indices.</dd>
8876
**
8877
** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
8878
** <dd>^This is the number of rows inserted into transient indices that
8879
** were created automatically in order to help joins run faster.
8880
** A non-zero value in this counter may indicate an opportunity to
8881
** improvement performance by adding permanent indices that do not
8882
** need to be reinitialized each time the statement is run.</dd>
8883
**
8884
** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
8885
** <dd>^This is the number of virtual machine operations executed
8886
** by the prepared statement if that number is less than or equal
8887
** to 2147483647.  The number of virtual machine operations can be
8888
** used as a proxy for the total work done by the prepared statement.
8889
** If the number of virtual machine operations exceeds 2147483647
8890
** then the value returned by this statement status code is undefined.
8891
**
8892
** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt>
8893
** <dd>^This is the number of times that the prepare statement has been
8894
** automatically regenerated due to schema changes or changes to
8895
** [bound parameters] that might affect the query plan.
8896
**
8897
** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt>
8898
** <dd>^This is the number of times that the prepared statement has
8899
** been run.  A single "run" for the purposes of this counter is one
8900
** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
8901
** The counter is incremented on the first [sqlite3_step()] call of each
8902
** cycle.
8903
**
8904
** [[SQLITE_STMTSTATUS_FILTER_MISS]]
8905
** [[SQLITE_STMTSTATUS_FILTER HIT]]
8906
** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br>
8907
** SQLITE_STMTSTATUS_FILTER_MISS</dt>
8908
** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join
8909
** step was bypassed because a Bloom filter returned not-found.  The
8910
** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of
8911
** times that the Bloom filter returned a find, and thus the join step
8912
** had to be processed as normal.
8913
**
8914
** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt>
8915
** <dd>^This is the approximate number of bytes of heap memory
8916
** used to store the prepared statement.  ^This value is not actually
8917
** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
8918
** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
8919
** </dd>
8920
** </dl>
8921
*/
8922
#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
8923
#define SQLITE_STMTSTATUS_SORT              2
8924
#define SQLITE_STMTSTATUS_AUTOINDEX         3
8925
#define SQLITE_STMTSTATUS_VM_STEP           4
8926
#define SQLITE_STMTSTATUS_REPREPARE         5
8927
#define SQLITE_STMTSTATUS_RUN               6
8928
#define SQLITE_STMTSTATUS_FILTER_MISS       7
8929
#define SQLITE_STMTSTATUS_FILTER_HIT        8
8930
#define SQLITE_STMTSTATUS_MEMUSED           99
8931
8932
/*
8933
** CAPI3REF: Custom Page Cache Object
8934
**
8935
** The sqlite3_pcache type is opaque.  It is implemented by
8936
** the pluggable module.  The SQLite core has no knowledge of
8937
** its size or internal structure and never deals with the
8938
** sqlite3_pcache object except by holding and passing pointers
8939
** to the object.
8940
**
8941
** See [sqlite3_pcache_methods2] for additional information.
8942
*/
8943
typedef struct sqlite3_pcache sqlite3_pcache;
8944
8945
/*
8946
** CAPI3REF: Custom Page Cache Object
8947
**
8948
** The sqlite3_pcache_page object represents a single page in the
8949
** page cache.  The page cache will allocate instances of this
8950
** object.  Various methods of the page cache use pointers to instances
8951
** of this object as parameters or as their return value.
8952
**
8953
** See [sqlite3_pcache_methods2] for additional information.
8954
*/
8955
typedef struct sqlite3_pcache_page sqlite3_pcache_page;
8956
struct sqlite3_pcache_page {
8957
  void *pBuf;        /* The content of the page */
8958
  void *pExtra;      /* Extra information associated with the page */
8959
};
8960
8961
/*
8962
** CAPI3REF: Application Defined Page Cache.
8963
** KEYWORDS: {page cache}
8964
**
8965
** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
8966
** register an alternative page cache implementation by passing in an
8967
** instance of the sqlite3_pcache_methods2 structure.)^
8968
** In many applications, most of the heap memory allocated by
8969
** SQLite is used for the page cache.
8970
** By implementing a
8971
** custom page cache using this API, an application can better control
8972
** the amount of memory consumed by SQLite, the way in which
8973
** that memory is allocated and released, and the policies used to
8974
** determine exactly which parts of a database file are cached and for
8975
** how long.
8976
**
8977
** The alternative page cache mechanism is an
8978
** extreme measure that is only needed by the most demanding applications.
8979
** The built-in page cache is recommended for most uses.
8980
**
8981
** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
8982
** internal buffer by SQLite within the call to [sqlite3_config].  Hence
8983
** the application may discard the parameter after the call to
8984
** [sqlite3_config()] returns.)^
8985
**
8986
** [[the xInit() page cache method]]
8987
** ^(The xInit() method is called once for each effective
8988
** call to [sqlite3_initialize()])^
8989
** (usually only once during the lifetime of the process). ^(The xInit()
8990
** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
8991
** The intent of the xInit() method is to set up global data structures
8992
** required by the custom page cache implementation.
8993
** ^(If the xInit() method is NULL, then the
8994
** built-in default page cache is used instead of the application defined
8995
** page cache.)^
8996
**
8997
** [[the xShutdown() page cache method]]
8998
** ^The xShutdown() method is called by [sqlite3_shutdown()].
8999
** It can be used to clean up
9000
** any outstanding resources before process shutdown, if required.
9001
** ^The xShutdown() method may be NULL.
9002
**
9003
** ^SQLite automatically serializes calls to the xInit method,
9004
** so the xInit method need not be threadsafe.  ^The
9005
** xShutdown method is only called from [sqlite3_shutdown()] so it does
9006
** not need to be threadsafe either.  All other methods must be threadsafe
9007
** in multithreaded applications.
9008
**
9009
** ^SQLite will never invoke xInit() more than once without an intervening
9010
** call to xShutdown().
9011
**
9012
** [[the xCreate() page cache methods]]
9013
** ^SQLite invokes the xCreate() method to construct a new cache instance.
9014
** SQLite will typically create one cache instance for each open database file,
9015
** though this is not guaranteed. ^The
9016
** first parameter, szPage, is the size in bytes of the pages that must
9017
** be allocated by the cache.  ^szPage will always a power of two.  ^The
9018
** second parameter szExtra is a number of bytes of extra storage
9019
** associated with each page cache entry.  ^The szExtra parameter will
9020
** a number less than 250.  SQLite will use the
9021
** extra szExtra bytes on each page to store metadata about the underlying
9022
** database page on disk.  The value passed into szExtra depends
9023
** on the SQLite version, the target platform, and how SQLite was compiled.
9024
** ^The third argument to xCreate(), bPurgeable, is true if the cache being
9025
** created will be used to cache database pages of a file stored on disk, or
9026
** false if it is used for an in-memory database. The cache implementation
9027
** does not have to do anything special based with the value of bPurgeable;
9028
** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
9029
** never invoke xUnpin() except to deliberately delete a page.
9030
** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
9031
** false will always have the "discard" flag set to true.
9032
** ^Hence, a cache created with bPurgeable false will
9033
** never contain any unpinned pages.
9034
**
9035
** [[the xCachesize() page cache method]]
9036
** ^(The xCachesize() method may be called at any time by SQLite to set the
9037
** suggested maximum cache-size (number of pages stored by) the cache
9038
** instance passed as the first argument. This is the value configured using
9039
** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
9040
** parameter, the implementation is not required to do anything with this
9041
** value; it is advisory only.
9042
**
9043
** [[the xPagecount() page cache methods]]
9044
** The xPagecount() method must return the number of pages currently
9045
** stored in the cache, both pinned and unpinned.
9046
**
9047
** [[the xFetch() page cache methods]]
9048
** The xFetch() method locates a page in the cache and returns a pointer to
9049
** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
9050
** The pBuf element of the returned sqlite3_pcache_page object will be a
9051
** pointer to a buffer of szPage bytes used to store the content of a
9052
** single database page.  The pExtra element of sqlite3_pcache_page will be
9053
** a pointer to the szExtra bytes of extra storage that SQLite has requested
9054
** for each entry in the page cache.
9055
**
9056
** The page to be fetched is determined by the key. ^The minimum key value
9057
** is 1.  After it has been retrieved using xFetch, the page is considered
9058
** to be "pinned".
9059
**
9060
** If the requested page is already in the page cache, then the page cache
9061
** implementation must return a pointer to the page buffer with its content
9062
** intact.  If the requested page is not already in the cache, then the
9063
** cache implementation should use the value of the createFlag
9064
** parameter to help it determined what action to take:
9065
**
9066
** <table border=1 width=85% align=center>
9067
** <tr><th> createFlag <th> Behavior when page is not already in cache
9068
** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
9069
** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
9070
**                 Otherwise return NULL.
9071
** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
9072
**                 NULL if allocating a new page is effectively impossible.
9073
** </table>
9074
**
9075
** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
9076
** will only use a createFlag of 2 after a prior call with a createFlag of 1
9077
** failed.)^  In between the xFetch() calls, SQLite may
9078
** attempt to unpin one or more cache pages by spilling the content of
9079
** pinned pages to disk and synching the operating system disk cache.
9080
**
9081
** [[the xUnpin() page cache method]]
9082
** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
9083
** as its second argument.  If the third parameter, discard, is non-zero,
9084
** then the page must be evicted from the cache.
9085
** ^If the discard parameter is
9086
** zero, then the page may be discarded or retained at the discretion of
9087
** page cache implementation. ^The page cache implementation
9088
** may choose to evict unpinned pages at any time.
9089
**
9090
** The cache must not perform any reference counting. A single
9091
** call to xUnpin() unpins the page regardless of the number of prior calls
9092
** to xFetch().
9093
**
9094
** [[the xRekey() page cache methods]]
9095
** The xRekey() method is used to change the key value associated with the
9096
** page passed as the second argument. If the cache
9097
** previously contains an entry associated with newKey, it must be
9098
** discarded. ^Any prior cache entry associated with newKey is guaranteed not
9099
** to be pinned.
9100
**
9101
** When SQLite calls the xTruncate() method, the cache must discard all
9102
** existing cache entries with page numbers (keys) greater than or equal
9103
** to the value of the iLimit parameter passed to xTruncate(). If any
9104
** of these pages are pinned, they are implicitly unpinned, meaning that
9105
** they can be safely discarded.
9106
**
9107
** [[the xDestroy() page cache method]]
9108
** ^The xDestroy() method is used to delete a cache allocated by xCreate().
9109
** All resources associated with the specified cache should be freed. ^After
9110
** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
9111
** handle invalid, and will not use it with any other sqlite3_pcache_methods2
9112
** functions.
9113
**
9114
** [[the xShrink() page cache method]]
9115
** ^SQLite invokes the xShrink() method when it wants the page cache to
9116
** free up as much of heap memory as possible.  The page cache implementation
9117
** is not obligated to free any memory, but well-behaved implementations should
9118
** do their best.
9119
*/
9120
typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
9121
struct sqlite3_pcache_methods2 {
9122
  int iVersion;
9123
  void *pArg;
9124
  int (*xInit)(void*);
9125
  void (*xShutdown)(void*);
9126
  sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
9127
  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
9128
  int (*xPagecount)(sqlite3_pcache*);
9129
  sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
9130
  void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
9131
  void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
9132
      unsigned oldKey, unsigned newKey);
9133
  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
9134
  void (*xDestroy)(sqlite3_pcache*);
9135
  void (*xShrink)(sqlite3_pcache*);
9136
};
9137
9138
/*
9139
** This is the obsolete pcache_methods object that has now been replaced
9140
** by sqlite3_pcache_methods2.  This object is not used by SQLite.  It is
9141
** retained in the header file for backwards compatibility only.
9142
*/
9143
typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
9144
struct sqlite3_pcache_methods {
9145
  void *pArg;
9146
  int (*xInit)(void*);
9147
  void (*xShutdown)(void*);
9148
  sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
9149
  void (*xCachesize)(sqlite3_pcache*, int nCachesize);
9150
  int (*xPagecount)(sqlite3_pcache*);
9151
  void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
9152
  void (*xUnpin)(sqlite3_pcache*, void*, int discard);
9153
  void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
9154
  void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
9155
  void (*xDestroy)(sqlite3_pcache*);
9156
};
9157
9158
9159
/*
9160
** CAPI3REF: Online Backup Object
9161
**
9162
** The sqlite3_backup object records state information about an ongoing
9163
** online backup operation.  ^The sqlite3_backup object is created by
9164
** a call to [sqlite3_backup_init()] and is destroyed by a call to
9165
** [sqlite3_backup_finish()].
9166
**
9167
** See Also: [Using the SQLite Online Backup API]
9168
*/
9169
typedef struct sqlite3_backup sqlite3_backup;
9170
9171
/*
9172
** CAPI3REF: Online Backup API.
9173
**
9174
** The backup API copies the content of one database into another.
9175
** It is useful either for creating backups of databases or
9176
** for copying in-memory databases to or from persistent files.
9177
**
9178
** See Also: [Using the SQLite Online Backup API]
9179
**
9180
** ^SQLite holds a write transaction open on the destination database file
9181
** for the duration of the backup operation.
9182
** ^The source database is read-locked only while it is being read;
9183
** it is not locked continuously for the entire backup operation.
9184
** ^Thus, the backup may be performed on a live source database without
9185
** preventing other database connections from
9186
** reading or writing to the source database while the backup is underway.
9187
**
9188
** ^(To perform a backup operation:
9189
**   <ol>
9190
**     <li><b>sqlite3_backup_init()</b> is called once to initialize the
9191
**         backup,
9192
**     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
9193
**         the data between the two databases, and finally
9194
**     <li><b>sqlite3_backup_finish()</b> is called to release all resources
9195
**         associated with the backup operation.
9196
**   </ol>)^
9197
** There should be exactly one call to sqlite3_backup_finish() for each
9198
** successful call to sqlite3_backup_init().
9199
**
9200
** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
9201
**
9202
** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
9203
** [database connection] associated with the destination database
9204
** and the database name, respectively.
9205
** ^The database name is "main" for the main database, "temp" for the
9206
** temporary database, or the name specified after the AS keyword in
9207
** an [ATTACH] statement for an attached database.
9208
** ^The S and M arguments passed to
9209
** sqlite3_backup_init(D,N,S,M) identify the [database connection]
9210
** and database name of the source database, respectively.
9211
** ^The source and destination [database connections] (parameters S and D)
9212
** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
9213
** an error.
9214
**
9215
** ^A call to sqlite3_backup_init() will fail, returning NULL, if
9216
** there is already a read or read-write transaction open on the
9217
** destination database.
9218
**
9219
** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
9220
** returned and an error code and error message are stored in the
9221
** destination [database connection] D.
9222
** ^The error code and message for the failed call to sqlite3_backup_init()
9223
** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
9224
** [sqlite3_errmsg16()] functions.
9225
** ^A successful call to sqlite3_backup_init() returns a pointer to an
9226
** [sqlite3_backup] object.
9227
** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
9228
** sqlite3_backup_finish() functions to perform the specified backup
9229
** operation.
9230
**
9231
** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
9232
**
9233
** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
9234
** the source and destination databases specified by [sqlite3_backup] object B.
9235
** ^If N is negative, all remaining source pages are copied.
9236
** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
9237
** are still more pages to be copied, then the function returns [SQLITE_OK].
9238
** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
9239
** from source to destination, then it returns [SQLITE_DONE].
9240
** ^If an error occurs while running sqlite3_backup_step(B,N),
9241
** then an [error code] is returned. ^As well as [SQLITE_OK] and
9242
** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
9243
** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
9244
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
9245
**
9246
** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
9247
** <ol>
9248
** <li> the destination database was opened read-only, or
9249
** <li> the destination database is using write-ahead-log journaling
9250
** and the destination and source page sizes differ, or
9251
** <li> the destination database is an in-memory database and the
9252
** destination and source page sizes differ.
9253
** </ol>)^
9254
**
9255
** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
9256
** the [sqlite3_busy_handler | busy-handler function]
9257
** is invoked (if one is specified). ^If the
9258
** busy-handler returns non-zero before the lock is available, then
9259
** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
9260
** sqlite3_backup_step() can be retried later. ^If the source
9261
** [database connection]
9262
** is being used to write to the source database when sqlite3_backup_step()
9263
** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
9264
** case the call to sqlite3_backup_step() can be retried later on. ^(If
9265
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
9266
** [SQLITE_READONLY] is returned, then
9267
** there is no point in retrying the call to sqlite3_backup_step(). These
9268
** errors are considered fatal.)^  The application must accept
9269
** that the backup operation has failed and pass the backup operation handle
9270
** to the sqlite3_backup_finish() to release associated resources.
9271
**
9272
** ^The first call to sqlite3_backup_step() obtains an exclusive lock
9273
** on the destination file. ^The exclusive lock is not released until either
9274
** sqlite3_backup_finish() is called or the backup operation is complete
9275
** and sqlite3_backup_step() returns [SQLITE_DONE].  ^Every call to
9276
** sqlite3_backup_step() obtains a [shared lock] on the source database that
9277
** lasts for the duration of the sqlite3_backup_step() call.
9278
** ^Because the source database is not locked between calls to
9279
** sqlite3_backup_step(), the source database may be modified mid-way
9280
** through the backup process.  ^If the source database is modified by an
9281
** external process or via a database connection other than the one being
9282
** used by the backup operation, then the backup will be automatically
9283
** restarted by the next call to sqlite3_backup_step(). ^If the source
9284
** database is modified by the using the same database connection as is used
9285
** by the backup operation, then the backup database is automatically
9286
** updated at the same time.
9287
**
9288
** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
9289
**
9290
** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
9291
** application wishes to abandon the backup operation, the application
9292
** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
9293
** ^The sqlite3_backup_finish() interfaces releases all
9294
** resources associated with the [sqlite3_backup] object.
9295
** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
9296
** active write-transaction on the destination database is rolled back.
9297
** The [sqlite3_backup] object is invalid
9298
** and may not be used following a call to sqlite3_backup_finish().
9299
**
9300
** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
9301
** sqlite3_backup_step() errors occurred, regardless or whether or not
9302
** sqlite3_backup_step() completed.
9303
** ^If an out-of-memory condition or IO error occurred during any prior
9304
** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
9305
** sqlite3_backup_finish() returns the corresponding [error code].
9306
**
9307
** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
9308
** is not a permanent error and does not affect the return value of
9309
** sqlite3_backup_finish().
9310
**
9311
** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
9312
** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
9313
**
9314
** ^The sqlite3_backup_remaining() routine returns the number of pages still
9315
** to be backed up at the conclusion of the most recent sqlite3_backup_step().
9316
** ^The sqlite3_backup_pagecount() routine returns the total number of pages
9317
** in the source database at the conclusion of the most recent
9318
** sqlite3_backup_step().
9319
** ^(The values returned by these functions are only updated by
9320
** sqlite3_backup_step(). If the source database is modified in a way that
9321
** changes the size of the source database or the number of pages remaining,
9322
** those changes are not reflected in the output of sqlite3_backup_pagecount()
9323
** and sqlite3_backup_remaining() until after the next
9324
** sqlite3_backup_step().)^
9325
**
9326
** <b>Concurrent Usage of Database Handles</b>
9327
**
9328
** ^The source [database connection] may be used by the application for other
9329
** purposes while a backup operation is underway or being initialized.
9330
** ^If SQLite is compiled and configured to support threadsafe database
9331
** connections, then the source database connection may be used concurrently
9332
** from within other threads.
9333
**
9334
** However, the application must guarantee that the destination
9335
** [database connection] is not passed to any other API (by any thread) after
9336
** sqlite3_backup_init() is called and before the corresponding call to
9337
** sqlite3_backup_finish().  SQLite does not currently check to see
9338
** if the application incorrectly accesses the destination [database connection]
9339
** and so no error code is reported, but the operations may malfunction
9340
** nevertheless.  Use of the destination database connection while a
9341
** backup is in progress might also cause a mutex deadlock.
9342
**
9343
** If running in [shared cache mode], the application must
9344
** guarantee that the shared cache used by the destination database
9345
** is not accessed while the backup is running. In practice this means
9346
** that the application must guarantee that the disk file being
9347
** backed up to is not accessed by any connection within the process,
9348
** not just the specific connection that was passed to sqlite3_backup_init().
9349
**
9350
** The [sqlite3_backup] object itself is partially threadsafe. Multiple
9351
** threads may safely make multiple concurrent calls to sqlite3_backup_step().
9352
** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
9353
** APIs are not strictly speaking threadsafe. If they are invoked at the
9354
** same time as another thread is invoking sqlite3_backup_step() it is
9355
** possible that they return invalid values.
9356
**
9357
** <b>Alternatives To Using The Backup API</b>
9358
**
9359
** Other techniques for safely creating a consistent backup of an SQLite
9360
** database include:
9361
**
9362
** <ul>
9363
** <li> The [VACUUM INTO] command.
9364
** <li> The [sqlite3_rsync] utility program.
9365
** </ul>
9366
*/
9367
SQLITE_API sqlite3_backup *sqlite3_backup_init(
9368
  sqlite3 *pDest,                        /* Destination database handle */
9369
  const char *zDestName,                 /* Destination database name */
9370
  sqlite3 *pSource,                      /* Source database handle */
9371
  const char *zSourceName                /* Source database name */
9372
);
9373
SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
9374
SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
9375
SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
9376
SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
9377
9378
/*
9379
** CAPI3REF: Unlock Notification
9380
** METHOD: sqlite3
9381
**
9382
** ^When running in shared-cache mode, a database operation may fail with
9383
** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
9384
** individual tables within the shared-cache cannot be obtained. See
9385
** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
9386
** ^This API may be used to register a callback that SQLite will invoke
9387
** when the connection currently holding the required lock relinquishes it.
9388
** ^This API is only available if the library was compiled with the
9389
** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
9390
**
9391
** See Also: [Using the SQLite Unlock Notification Feature].
9392
**
9393
** ^Shared-cache locks are released when a database connection concludes
9394
** its current transaction, either by committing it or rolling it back.
9395
**
9396
** ^When a connection (known as the blocked connection) fails to obtain a
9397
** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
9398
** identity of the database connection (the blocking connection) that
9399
** has locked the required resource is stored internally. ^After an
9400
** application receives an SQLITE_LOCKED error, it may call the
9401
** sqlite3_unlock_notify() method with the blocked connection handle as
9402
** the first argument to register for a callback that will be invoked
9403
** when the blocking connections current transaction is concluded. ^The
9404
** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
9405
** call that concludes the blocking connection's transaction.
9406
**
9407
** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
9408
** there is a chance that the blocking connection will have already
9409
** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
9410
** If this happens, then the specified callback is invoked immediately,
9411
** from within the call to sqlite3_unlock_notify().)^
9412
**
9413
** ^If the blocked connection is attempting to obtain a write-lock on a
9414
** shared-cache table, and more than one other connection currently holds
9415
** a read-lock on the same table, then SQLite arbitrarily selects one of
9416
** the other connections to use as the blocking connection.
9417
**
9418
** ^(There may be at most one unlock-notify callback registered by a
9419
** blocked connection. If sqlite3_unlock_notify() is called when the
9420
** blocked connection already has a registered unlock-notify callback,
9421
** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
9422
** called with a NULL pointer as its second argument, then any existing
9423
** unlock-notify callback is canceled. ^The blocked connections
9424
** unlock-notify callback may also be canceled by closing the blocked
9425
** connection using [sqlite3_close()].
9426
**
9427
** The unlock-notify callback is not reentrant. If an application invokes
9428
** any sqlite3_xxx API functions from within an unlock-notify callback, a
9429
** crash or deadlock may be the result.
9430
**
9431
** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
9432
** returns SQLITE_OK.
9433
**
9434
** <b>Callback Invocation Details</b>
9435
**
9436
** When an unlock-notify callback is registered, the application provides a
9437
** single void* pointer that is passed to the callback when it is invoked.
9438
** However, the signature of the callback function allows SQLite to pass
9439
** it an array of void* context pointers. The first argument passed to
9440
** an unlock-notify callback is a pointer to an array of void* pointers,
9441
** and the second is the number of entries in the array.
9442
**
9443
** When a blocking connection's transaction is concluded, there may be
9444
** more than one blocked connection that has registered for an unlock-notify
9445
** callback. ^If two or more such blocked connections have specified the
9446
** same callback function, then instead of invoking the callback function
9447
** multiple times, it is invoked once with the set of void* context pointers
9448
** specified by the blocked connections bundled together into an array.
9449
** This gives the application an opportunity to prioritize any actions
9450
** related to the set of unblocked database connections.
9451
**
9452
** <b>Deadlock Detection</b>
9453
**
9454
** Assuming that after registering for an unlock-notify callback a
9455
** database waits for the callback to be issued before taking any further
9456
** action (a reasonable assumption), then using this API may cause the
9457
** application to deadlock. For example, if connection X is waiting for
9458
** connection Y's transaction to be concluded, and similarly connection
9459
** Y is waiting on connection X's transaction, then neither connection
9460
** will proceed and the system may remain deadlocked indefinitely.
9461
**
9462
** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
9463
** detection. ^If a given call to sqlite3_unlock_notify() would put the
9464
** system in a deadlocked state, then SQLITE_LOCKED is returned and no
9465
** unlock-notify callback is registered. The system is said to be in
9466
** a deadlocked state if connection A has registered for an unlock-notify
9467
** callback on the conclusion of connection B's transaction, and connection
9468
** B has itself registered for an unlock-notify callback when connection
9469
** A's transaction is concluded. ^Indirect deadlock is also detected, so
9470
** the system is also considered to be deadlocked if connection B has
9471
** registered for an unlock-notify callback on the conclusion of connection
9472
** C's transaction, where connection C is waiting on connection A. ^Any
9473
** number of levels of indirection are allowed.
9474
**
9475
** <b>The "DROP TABLE" Exception</b>
9476
**
9477
** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
9478
** always appropriate to call sqlite3_unlock_notify(). There is however,
9479
** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
9480
** SQLite checks if there are any currently executing SELECT statements
9481
** that belong to the same connection. If there are, SQLITE_LOCKED is
9482
** returned. In this case there is no "blocking connection", so invoking
9483
** sqlite3_unlock_notify() results in the unlock-notify callback being
9484
** invoked immediately. If the application then re-attempts the "DROP TABLE"
9485
** or "DROP INDEX" query, an infinite loop might be the result.
9486
**
9487
** One way around this problem is to check the extended error code returned
9488
** by an sqlite3_step() call. ^(If there is a blocking connection, then the
9489
** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
9490
** the special "DROP TABLE/INDEX" case, the extended error code is just
9491
** SQLITE_LOCKED.)^
9492
*/
9493
SQLITE_API int sqlite3_unlock_notify(
9494
  sqlite3 *pBlocked,                          /* Waiting connection */
9495
  void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
9496
  void *pNotifyArg                            /* Argument to pass to xNotify */
9497
);
9498
9499
9500
/*
9501
** CAPI3REF: String Comparison
9502
**
9503
** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
9504
** and extensions to compare the contents of two buffers containing UTF-8
9505
** strings in a case-independent fashion, using the same definition of "case
9506
** independence" that SQLite uses internally when comparing identifiers.
9507
*/
9508
SQLITE_API int sqlite3_stricmp(const char *, const char *);
9509
SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
9510
9511
/*
9512
** CAPI3REF: String Globbing
9513
*
9514
** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
9515
** string X matches the [GLOB] pattern P.
9516
** ^The definition of [GLOB] pattern matching used in
9517
** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
9518
** SQL dialect understood by SQLite.  ^The [sqlite3_strglob(P,X)] function
9519
** is case sensitive.
9520
**
9521
** Note that this routine returns zero on a match and non-zero if the strings
9522
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
9523
**
9524
** See also: [sqlite3_strlike()].
9525
*/
9526
SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
9527
9528
/*
9529
** CAPI3REF: String LIKE Matching
9530
*
9531
** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
9532
** string X matches the [LIKE] pattern P with escape character E.
9533
** ^The definition of [LIKE] pattern matching used in
9534
** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
9535
** operator in the SQL dialect understood by SQLite.  ^For "X LIKE P" without
9536
** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
9537
** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
9538
** insensitive - equivalent upper and lower case ASCII characters match
9539
** one another.
9540
**
9541
** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
9542
** only ASCII characters are case folded.
9543
**
9544
** Note that this routine returns zero on a match and non-zero if the strings
9545
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
9546
**
9547
** See also: [sqlite3_strglob()].
9548
*/
9549
SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
9550
9551
/*
9552
** CAPI3REF: Error Logging Interface
9553
**
9554
** ^The [sqlite3_log()] interface writes a message into the [error log]
9555
** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
9556
** ^If logging is enabled, the zFormat string and subsequent arguments are
9557
** used with [sqlite3_snprintf()] to generate the final output string.
9558
**
9559
** The sqlite3_log() interface is intended for use by extensions such as
9560
** virtual tables, collating functions, and SQL functions.  While there is
9561
** nothing to prevent an application from calling sqlite3_log(), doing so
9562
** is considered bad form.
9563
**
9564
** The zFormat string must not be NULL.
9565
**
9566
** To avoid deadlocks and other threading problems, the sqlite3_log() routine
9567
** will not use dynamically allocated memory.  The log message is stored in
9568
** a fixed-length buffer on the stack.  If the log message is longer than
9569
** a few hundred characters, it will be truncated to the length of the
9570
** buffer.
9571
*/
9572
SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
9573
9574
/*
9575
** CAPI3REF: Write-Ahead Log Commit Hook
9576
** METHOD: sqlite3
9577
**
9578
** ^The [sqlite3_wal_hook()] function is used to register a callback that
9579
** is invoked each time data is committed to a database in wal mode.
9580
**
9581
** ^(The callback is invoked by SQLite after the commit has taken place and
9582
** the associated write-lock on the database released)^, so the implementation
9583
** may read, write or [checkpoint] the database as required.
9584
**
9585
** ^The first parameter passed to the callback function when it is invoked
9586
** is a copy of the third parameter passed to sqlite3_wal_hook() when
9587
** registering the callback. ^The second is a copy of the database handle.
9588
** ^The third parameter is the name of the database that was written to -
9589
** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
9590
** is the number of pages currently in the write-ahead log file,
9591
** including those that were just committed.
9592
**
9593
** The callback function should normally return [SQLITE_OK].  ^If an error
9594
** code is returned, that error will propagate back up through the
9595
** SQLite code base to cause the statement that provoked the callback
9596
** to report an error, though the commit will have still occurred. If the
9597
** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
9598
** that does not correspond to any valid SQLite error code, the results
9599
** are undefined.
9600
**
9601
** A single database handle may have at most a single write-ahead log callback
9602
** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
9603
** previously registered write-ahead log callback. ^The return value is
9604
** a copy of the third parameter from the previous call, if any, or 0.
9605
** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the
9606
** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
9607
** overwrite any prior [sqlite3_wal_hook()] settings.
9608
*/
9609
SQLITE_API void *sqlite3_wal_hook(
9610
  sqlite3*,
9611
  int(*)(void *,sqlite3*,const char*,int),
9612
  void*
9613
);
9614
9615
/*
9616
** CAPI3REF: Configure an auto-checkpoint
9617
** METHOD: sqlite3
9618
**
9619
** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
9620
** [sqlite3_wal_hook()] that causes any database on [database connection] D
9621
** to automatically [checkpoint]
9622
** after committing a transaction if there are N or
9623
** more frames in the [write-ahead log] file.  ^Passing zero or
9624
** a negative value as the nFrame parameter disables automatic
9625
** checkpoints entirely.
9626
**
9627
** ^The callback registered by this function replaces any existing callback
9628
** registered using [sqlite3_wal_hook()].  ^Likewise, registering a callback
9629
** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
9630
** configured by this function.
9631
**
9632
** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
9633
** from SQL.
9634
**
9635
** ^Checkpoints initiated by this mechanism are
9636
** [sqlite3_wal_checkpoint_v2|PASSIVE].
9637
**
9638
** ^Every new [database connection] defaults to having the auto-checkpoint
9639
** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
9640
** pages.  The use of this interface
9641
** is only necessary if the default setting is found to be suboptimal
9642
** for a particular application.
9643
*/
9644
SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
9645
9646
/*
9647
** CAPI3REF: Checkpoint a database
9648
** METHOD: sqlite3
9649
**
9650
** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
9651
** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
9652
**
9653
** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
9654
** [write-ahead log] for database X on [database connection] D to be
9655
** transferred into the database file and for the write-ahead log to
9656
** be reset.  See the [checkpointing] documentation for addition
9657
** information.
9658
**
9659
** This interface used to be the only way to cause a checkpoint to
9660
** occur.  But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
9661
** interface was added.  This interface is retained for backwards
9662
** compatibility and as a convenience for applications that need to manually
9663
** start a callback but which do not need the full power (and corresponding
9664
** complication) of [sqlite3_wal_checkpoint_v2()].
9665
*/
9666
SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
9667
9668
/*
9669
** CAPI3REF: Checkpoint a database
9670
** METHOD: sqlite3
9671
**
9672
** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
9673
** operation on database X of [database connection] D in mode M.  Status
9674
** information is written back into integers pointed to by L and C.)^
9675
** ^(The M parameter must be a valid [checkpoint mode]:)^
9676
**
9677
** <dl>
9678
** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
9679
**   ^Checkpoint as many frames as possible without waiting for any database
9680
**   readers or writers to finish, then sync the database file if all frames
9681
**   in the log were checkpointed. ^The [busy-handler callback]
9682
**   is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
9683
**   ^On the other hand, passive mode might leave the checkpoint unfinished
9684
**   if there are concurrent readers or writers.
9685
**
9686
** <dt>SQLITE_CHECKPOINT_FULL<dd>
9687
**   ^This mode blocks (it invokes the
9688
**   [sqlite3_busy_handler|busy-handler callback]) until there is no
9689
**   database writer and all readers are reading from the most recent database
9690
**   snapshot. ^It then checkpoints all frames in the log file and syncs the
9691
**   database file. ^This mode blocks new database writers while it is pending,
9692
**   but new database readers are allowed to continue unimpeded.
9693
**
9694
** <dt>SQLITE_CHECKPOINT_RESTART<dd>
9695
**   ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
9696
**   that after checkpointing the log file it blocks (calls the
9697
**   [busy-handler callback])
9698
**   until all readers are reading from the database file only. ^This ensures
9699
**   that the next writer will restart the log file from the beginning.
9700
**   ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
9701
**   database writer attempts while it is pending, but does not impede readers.
9702
**
9703
** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
9704
**   ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
9705
**   addition that it also truncates the log file to zero bytes just prior
9706
**   to a successful return.
9707
** </dl>
9708
**
9709
** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
9710
** the log file or to -1 if the checkpoint could not run because
9711
** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
9712
** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
9713
** log file (including any that were already checkpointed before the function
9714
** was called) or to -1 if the checkpoint could not run due to an error or
9715
** because the database is not in WAL mode. ^Note that upon successful
9716
** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
9717
** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
9718
**
9719
** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
9720
** any other process is running a checkpoint operation at the same time, the
9721
** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
9722
** busy-handler configured, it will not be invoked in this case.
9723
**
9724
** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
9725
** exclusive "writer" lock on the database file. ^If the writer lock cannot be
9726
** obtained immediately, and a busy-handler is configured, it is invoked and
9727
** the writer lock retried until either the busy-handler returns 0 or the lock
9728
** is successfully obtained. ^The busy-handler is also invoked while waiting for
9729
** database readers as described above. ^If the busy-handler returns 0 before
9730
** the writer lock is obtained or while waiting for database readers, the
9731
** checkpoint operation proceeds from that point in the same way as
9732
** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
9733
** without blocking any further. ^SQLITE_BUSY is returned in this case.
9734
**
9735
** ^If parameter zDb is NULL or points to a zero length string, then the
9736
** specified operation is attempted on all WAL databases [attached] to
9737
** [database connection] db.  In this case the
9738
** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
9739
** an SQLITE_BUSY error is encountered when processing one or more of the
9740
** attached WAL databases, the operation is still attempted on any remaining
9741
** attached databases and SQLITE_BUSY is returned at the end. ^If any other
9742
** error occurs while processing an attached database, processing is abandoned
9743
** and the error code is returned to the caller immediately. ^If no error
9744
** (SQLITE_BUSY or otherwise) is encountered while processing the attached
9745
** databases, SQLITE_OK is returned.
9746
**
9747
** ^If database zDb is the name of an attached database that is not in WAL
9748
** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
9749
** zDb is not NULL (or a zero length string) and is not the name of any
9750
** attached database, SQLITE_ERROR is returned to the caller.
9751
**
9752
** ^Unless it returns SQLITE_MISUSE,
9753
** the sqlite3_wal_checkpoint_v2() interface
9754
** sets the error information that is queried by
9755
** [sqlite3_errcode()] and [sqlite3_errmsg()].
9756
**
9757
** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
9758
** from SQL.
9759
*/
9760
SQLITE_API int sqlite3_wal_checkpoint_v2(
9761
  sqlite3 *db,                    /* Database handle */
9762
  const char *zDb,                /* Name of attached database (or NULL) */
9763
  int eMode,                      /* SQLITE_CHECKPOINT_* value */
9764
  int *pnLog,                     /* OUT: Size of WAL log in frames */
9765
  int *pnCkpt                     /* OUT: Total number of frames checkpointed */
9766
);
9767
9768
/*
9769
** CAPI3REF: Checkpoint Mode Values
9770
** KEYWORDS: {checkpoint mode}
9771
**
9772
** These constants define all valid values for the "checkpoint mode" passed
9773
** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
9774
** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
9775
** meaning of each of these checkpoint modes.
9776
*/
9777
#define SQLITE_CHECKPOINT_PASSIVE  0  /* Do as much as possible w/o blocking */
9778
#define SQLITE_CHECKPOINT_FULL     1  /* Wait for writers, then checkpoint */
9779
#define SQLITE_CHECKPOINT_RESTART  2  /* Like FULL but wait for readers */
9780
#define SQLITE_CHECKPOINT_TRUNCATE 3  /* Like RESTART but also truncate WAL */
9781
9782
/*
9783
** CAPI3REF: Virtual Table Interface Configuration
9784
**
9785
** This function may be called by either the [xConnect] or [xCreate] method
9786
** of a [virtual table] implementation to configure
9787
** various facets of the virtual table interface.
9788
**
9789
** If this interface is invoked outside the context of an xConnect or
9790
** xCreate virtual table method then the behavior is undefined.
9791
**
9792
** In the call sqlite3_vtab_config(D,C,...) the D parameter is the
9793
** [database connection] in which the virtual table is being created and
9794
** which is passed in as the first argument to the [xConnect] or [xCreate]
9795
** method that is invoking sqlite3_vtab_config().  The C parameter is one
9796
** of the [virtual table configuration options].  The presence and meaning
9797
** of parameters after C depend on which [virtual table configuration option]
9798
** is used.
9799
*/
9800
SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
9801
9802
/*
9803
** CAPI3REF: Virtual Table Configuration Options
9804
** KEYWORDS: {virtual table configuration options}
9805
** KEYWORDS: {virtual table configuration option}
9806
**
9807
** These macros define the various options to the
9808
** [sqlite3_vtab_config()] interface that [virtual table] implementations
9809
** can use to customize and optimize their behavior.
9810
**
9811
** <dl>
9812
** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]]
9813
** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt>
9814
** <dd>Calls of the form
9815
** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
9816
** where X is an integer.  If X is zero, then the [virtual table] whose
9817
** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
9818
** support constraints.  In this configuration (which is the default) if
9819
** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
9820
** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
9821
** specified as part of the users SQL statement, regardless of the actual
9822
** ON CONFLICT mode specified.
9823
**
9824
** If X is non-zero, then the virtual table implementation guarantees
9825
** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
9826
** any modifications to internal or persistent data structures have been made.
9827
** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
9828
** is able to roll back a statement or database transaction, and abandon
9829
** or continue processing the current SQL statement as appropriate.
9830
** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
9831
** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
9832
** had been ABORT.
9833
**
9834
** Virtual table implementations that are required to handle OR REPLACE
9835
** must do so within the [xUpdate] method. If a call to the
9836
** [sqlite3_vtab_on_conflict()] function indicates that the current ON
9837
** CONFLICT policy is REPLACE, the virtual table implementation should
9838
** silently replace the appropriate rows within the xUpdate callback and
9839
** return SQLITE_OK. Or, if this is not possible, it may return
9840
** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
9841
** constraint handling.
9842
** </dd>
9843
**
9844
** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt>
9845
** <dd>Calls of the form
9846
** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the
9847
** the [xConnect] or [xCreate] methods of a [virtual table] implementation
9848
** prohibits that virtual table from being used from within triggers and
9849
** views.
9850
** </dd>
9851
**
9852
** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt>
9853
** <dd>Calls of the form
9854
** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the
9855
** the [xConnect] or [xCreate] methods of a [virtual table] implementation
9856
** identify that virtual table as being safe to use from within triggers
9857
** and views.  Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the
9858
** virtual table can do no serious harm even if it is controlled by a
9859
** malicious hacker.  Developers should avoid setting the SQLITE_VTAB_INNOCUOUS
9860
** flag unless absolutely necessary.
9861
** </dd>
9862
**
9863
** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]<dt>SQLITE_VTAB_USES_ALL_SCHEMAS</dt>
9864
** <dd>Calls of the form
9865
** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the
9866
** the [xConnect] or [xCreate] methods of a [virtual table] implementation
9867
** instruct the query planner to begin at least a read transaction on
9868
** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the
9869
** virtual table is used.
9870
** </dd>
9871
** </dl>
9872
*/
9873
#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
9874
#define SQLITE_VTAB_INNOCUOUS          2
9875
#define SQLITE_VTAB_DIRECTONLY         3
9876
#define SQLITE_VTAB_USES_ALL_SCHEMAS   4
9877
9878
/*
9879
** CAPI3REF: Determine The Virtual Table Conflict Policy
9880
**
9881
** This function may only be called from within a call to the [xUpdate] method
9882
** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
9883
** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
9884
** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
9885
** of the SQL statement that triggered the call to the [xUpdate] method of the
9886
** [virtual table].
9887
*/
9888
SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
9889
9890
/*
9891
** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE
9892
**
9893
** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn]
9894
** method of a [virtual table], then it might return true if the
9895
** column is being fetched as part of an UPDATE operation during which the
9896
** column value will not change.  The virtual table implementation can use
9897
** this hint as permission to substitute a return value that is less
9898
** expensive to compute and that the corresponding
9899
** [xUpdate] method understands as a "no-change" value.
9900
**
9901
** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that
9902
** the column is not changed by the UPDATE statement, then the xColumn
9903
** method can optionally return without setting a result, without calling
9904
** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces].
9905
** In that case, [sqlite3_value_nochange(X)] will return true for the
9906
** same column in the [xUpdate] method.
9907
**
9908
** The sqlite3_vtab_nochange() routine is an optimization.  Virtual table
9909
** implementations should continue to give a correct answer even if the
9910
** sqlite3_vtab_nochange() interface were to always return false.  In the
9911
** current implementation, the sqlite3_vtab_nochange() interface does always
9912
** returns false for the enhanced [UPDATE FROM] statement.
9913
*/
9914
SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*);
9915
9916
/*
9917
** CAPI3REF: Determine The Collation For a Virtual Table Constraint
9918
** METHOD: sqlite3_index_info
9919
**
9920
** This function may only be called from within a call to the [xBestIndex]
9921
** method of a [virtual table].  This function returns a pointer to a string
9922
** that is the name of the appropriate collation sequence to use for text
9923
** comparisons on the constraint identified by its arguments.
9924
**
9925
** The first argument must be the pointer to the [sqlite3_index_info] object
9926
** that is the first parameter to the xBestIndex() method. The second argument
9927
** must be an index into the aConstraint[] array belonging to the
9928
** sqlite3_index_info structure passed to xBestIndex.
9929
**
9930
** Important:
9931
** The first parameter must be the same pointer that is passed into the
9932
** xBestMethod() method.  The first parameter may not be a pointer to a
9933
** different [sqlite3_index_info] object, even an exact copy.
9934
**
9935
** The return value is computed as follows:
9936
**
9937
** <ol>
9938
** <li><p> If the constraint comes from a WHERE clause expression that contains
9939
**         a [COLLATE operator], then the name of the collation specified by
9940
**         that COLLATE operator is returned.
9941
** <li><p> If there is no COLLATE operator, but the column that is the subject
9942
**         of the constraint specifies an alternative collating sequence via
9943
**         a [COLLATE clause] on the column definition within the CREATE TABLE
9944
**         statement that was passed into [sqlite3_declare_vtab()], then the
9945
**         name of that alternative collating sequence is returned.
9946
** <li><p> Otherwise, "BINARY" is returned.
9947
** </ol>
9948
*/
9949
SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int);
9950
9951
/*
9952
** CAPI3REF: Determine if a virtual table query is DISTINCT
9953
** METHOD: sqlite3_index_info
9954
**
9955
** This API may only be used from within an [xBestIndex|xBestIndex method]
9956
** of a [virtual table] implementation. The result of calling this
9957
** interface from outside of xBestIndex() is undefined and probably harmful.
9958
**
9959
** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and
9960
** 3.  The integer returned by sqlite3_vtab_distinct()
9961
** gives the virtual table additional information about how the query
9962
** planner wants the output to be ordered. As long as the virtual table
9963
** can meet the ordering requirements of the query planner, it may set
9964
** the "orderByConsumed" flag.
9965
**
9966
** <ol><li value="0"><p>
9967
** ^If the sqlite3_vtab_distinct() interface returns 0, that means
9968
** that the query planner needs the virtual table to return all rows in the
9969
** sort order defined by the "nOrderBy" and "aOrderBy" fields of the
9970
** [sqlite3_index_info] object.  This is the default expectation.  If the
9971
** virtual table outputs all rows in sorted order, then it is always safe for
9972
** the xBestIndex method to set the "orderByConsumed" flag, regardless of
9973
** the return value from sqlite3_vtab_distinct().
9974
** <li value="1"><p>
9975
** ^(If the sqlite3_vtab_distinct() interface returns 1, that means
9976
** that the query planner does not need the rows to be returned in sorted order
9977
** as long as all rows with the same values in all columns identified by the
9978
** "aOrderBy" field are adjacent.)^  This mode is used when the query planner
9979
** is doing a GROUP BY.
9980
** <li value="2"><p>
9981
** ^(If the sqlite3_vtab_distinct() interface returns 2, that means
9982
** that the query planner does not need the rows returned in any particular
9983
** order, as long as rows with the same values in all columns identified
9984
** by "aOrderBy" are adjacent.)^  ^(Furthermore, when two or more rows
9985
** contain the same values for all columns identified by "colUsed", all but
9986
** one such row may optionally be omitted from the result.)^
9987
** The virtual table is not required to omit rows that are duplicates
9988
** over the "colUsed" columns, but if the virtual table can do that without
9989
** too much extra effort, it could potentially help the query to run faster.
9990
** This mode is used for a DISTINCT query.
9991
** <li value="3"><p>
9992
** ^(If the sqlite3_vtab_distinct() interface returns 3, that means the
9993
** virtual table must return rows in the order defined by "aOrderBy" as
9994
** if the sqlite3_vtab_distinct() interface had returned 0.  However if
9995
** two or more rows in the result have the same values for all columns
9996
** identified by "colUsed", then all but one such row may optionally be
9997
** omitted.)^  Like when the return value is 2, the virtual table
9998
** is not required to omit rows that are duplicates over the "colUsed"
9999
** columns, but if the virtual table can do that without
10000
** too much extra effort, it could potentially help the query to run faster.
10001
** This mode is used for queries
10002
** that have both DISTINCT and ORDER BY clauses.
10003
** </ol>
10004
**
10005
** <p>The following table summarizes the conditions under which the
10006
** virtual table is allowed to set the "orderByConsumed" flag based on
10007
** the value returned by sqlite3_vtab_distinct().  This table is a
10008
** restatement of the previous four paragraphs:
10009
**
10010
** <table border=1 cellspacing=0 cellpadding=10 width="90%">
10011
** <tr>
10012
** <td valign="top">sqlite3_vtab_distinct() return value
10013
** <td valign="top">Rows are returned in aOrderBy order
10014
** <td valign="top">Rows with the same value in all aOrderBy columns are adjacent
10015
** <td valign="top">Duplicates over all colUsed columns may be omitted
10016
** <tr><td>0<td>yes<td>yes<td>no
10017
** <tr><td>1<td>no<td>yes<td>no
10018
** <tr><td>2<td>no<td>yes<td>yes
10019
** <tr><td>3<td>yes<td>yes<td>yes
10020
** </table>
10021
**
10022
** ^For the purposes of comparing virtual table output values to see if the
10023
** values are same value for sorting purposes, two NULL values are considered
10024
** to be the same.  In other words, the comparison operator is "IS"
10025
** (or "IS NOT DISTINCT FROM") and not "==".
10026
**
10027
** If a virtual table implementation is unable to meet the requirements
10028
** specified above, then it must not set the "orderByConsumed" flag in the
10029
** [sqlite3_index_info] object or an incorrect answer may result.
10030
**
10031
** ^A virtual table implementation is always free to return rows in any order
10032
** it wants, as long as the "orderByConsumed" flag is not set.  ^When the
10033
** the "orderByConsumed" flag is unset, the query planner will add extra
10034
** [bytecode] to ensure that the final results returned by the SQL query are
10035
** ordered correctly.  The use of the "orderByConsumed" flag and the
10036
** sqlite3_vtab_distinct() interface is merely an optimization.  ^Careful
10037
** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed"
10038
** flag might help queries against a virtual table to run faster.  Being
10039
** overly aggressive and setting the "orderByConsumed" flag when it is not
10040
** valid to do so, on the other hand, might cause SQLite to return incorrect
10041
** results.
10042
*/
10043
SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*);
10044
10045
/*
10046
** CAPI3REF: Identify and handle IN constraints in xBestIndex
10047
**
10048
** This interface may only be used from within an
10049
** [xBestIndex|xBestIndex() method] of a [virtual table] implementation.
10050
** The result of invoking this interface from any other context is
10051
** undefined and probably harmful.
10052
**
10053
** ^(A constraint on a virtual table of the form
10054
** "[IN operator|column IN (...)]" is
10055
** communicated to the xBestIndex method as a
10056
** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^  If xBestIndex wants to use
10057
** this constraint, it must set the corresponding
10058
** aConstraintUsage[].argvIndex to a positive integer.  ^(Then, under
10059
** the usual mode of handling IN operators, SQLite generates [bytecode]
10060
** that invokes the [xFilter|xFilter() method] once for each value
10061
** on the right-hand side of the IN operator.)^  Thus the virtual table
10062
** only sees a single value from the right-hand side of the IN operator
10063
** at a time.
10064
**
10065
** In some cases, however, it would be advantageous for the virtual
10066
** table to see all values on the right-hand of the IN operator all at
10067
** once.  The sqlite3_vtab_in() interfaces facilitates this in two ways:
10068
**
10069
** <ol>
10070
** <li><p>
10071
**   ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero)
10072
**   if and only if the [sqlite3_index_info|P->aConstraint][N] constraint
10073
**   is an [IN operator] that can be processed all at once.  ^In other words,
10074
**   sqlite3_vtab_in() with -1 in the third argument is a mechanism
10075
**   by which the virtual table can ask SQLite if all-at-once processing
10076
**   of the IN operator is even possible.
10077
**
10078
** <li><p>
10079
**   ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates
10080
**   to SQLite that the virtual table does or does not want to process
10081
**   the IN operator all-at-once, respectively.  ^Thus when the third
10082
**   parameter (F) is non-negative, this interface is the mechanism by
10083
**   which the virtual table tells SQLite how it wants to process the
10084
**   IN operator.
10085
** </ol>
10086
**
10087
** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times
10088
** within the same xBestIndex method call.  ^For any given P,N pair,
10089
** the return value from sqlite3_vtab_in(P,N,F) will always be the same
10090
** within the same xBestIndex call.  ^If the interface returns true
10091
** (non-zero), that means that the constraint is an IN operator
10092
** that can be processed all-at-once.  ^If the constraint is not an IN
10093
** operator or cannot be processed all-at-once, then the interface returns
10094
** false.
10095
**
10096
** ^(All-at-once processing of the IN operator is selected if both of the
10097
** following conditions are met:
10098
**
10099
** <ol>
10100
** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive
10101
** integer.  This is how the virtual table tells SQLite that it wants to
10102
** use the N-th constraint.
10103
**
10104
** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was
10105
** non-negative had F>=1.
10106
** </ol>)^
10107
**
10108
** ^If either or both of the conditions above are false, then SQLite uses
10109
** the traditional one-at-a-time processing strategy for the IN constraint.
10110
** ^If both conditions are true, then the argvIndex-th parameter to the
10111
** xFilter method will be an [sqlite3_value] that appears to be NULL,
10112
** but which can be passed to [sqlite3_vtab_in_first()] and
10113
** [sqlite3_vtab_in_next()] to find all values on the right-hand side
10114
** of the IN constraint.
10115
*/
10116
SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle);
10117
10118
/*
10119
** CAPI3REF: Find all elements on the right-hand side of an IN constraint.
10120
**
10121
** These interfaces are only useful from within the
10122
** [xFilter|xFilter() method] of a [virtual table] implementation.
10123
** The result of invoking these interfaces from any other context
10124
** is undefined and probably harmful.
10125
**
10126
** The X parameter in a call to sqlite3_vtab_in_first(X,P) or
10127
** sqlite3_vtab_in_next(X,P) should be one of the parameters to the
10128
** xFilter method which invokes these routines, and specifically
10129
** a parameter that was previously selected for all-at-once IN constraint
10130
** processing use the [sqlite3_vtab_in()] interface in the
10131
** [xBestIndex|xBestIndex method].  ^(If the X parameter is not
10132
** an xFilter argument that was selected for all-at-once IN constraint
10133
** processing, then these routines return [SQLITE_ERROR].)^
10134
**
10135
** ^(Use these routines to access all values on the right-hand side
10136
** of the IN constraint using code like the following:
10137
**
10138
** <blockquote><pre>
10139
** &nbsp;  for(rc=sqlite3_vtab_in_first(pList, &pVal);
10140
** &nbsp;      rc==SQLITE_OK && pVal;
10141
** &nbsp;      rc=sqlite3_vtab_in_next(pList, &pVal)
10142
** &nbsp;  ){
10143
** &nbsp;    // do something with pVal
10144
** &nbsp;  }
10145
** &nbsp;  if( rc!=SQLITE_OK ){
10146
** &nbsp;    // an error has occurred
10147
** &nbsp;  }
10148
** </pre></blockquote>)^
10149
**
10150
** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P)
10151
** routines return SQLITE_OK and set *P to point to the first or next value
10152
** on the RHS of the IN constraint.  ^If there are no more values on the
10153
** right hand side of the IN constraint, then *P is set to NULL and these
10154
** routines return [SQLITE_DONE].  ^The return value might be
10155
** some other value, such as SQLITE_NOMEM, in the event of a malfunction.
10156
**
10157
** The *ppOut values returned by these routines are only valid until the
10158
** next call to either of these routines or until the end of the xFilter
10159
** method from which these routines were called.  If the virtual table
10160
** implementation needs to retain the *ppOut values for longer, it must make
10161
** copies.  The *ppOut values are [protected sqlite3_value|protected].
10162
*/
10163
SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut);
10164
SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut);
10165
10166
/*
10167
** CAPI3REF: Constraint values in xBestIndex()
10168
** METHOD: sqlite3_index_info
10169
**
10170
** This API may only be used from within the [xBestIndex|xBestIndex method]
10171
** of a [virtual table] implementation. The result of calling this interface
10172
** from outside of an xBestIndex method are undefined and probably harmful.
10173
**
10174
** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within
10175
** the [xBestIndex] method of a [virtual table] implementation, with P being
10176
** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and
10177
** J being a 0-based index into P->aConstraint[], then this routine
10178
** attempts to set *V to the value of the right-hand operand of
10179
** that constraint if the right-hand operand is known.  ^If the
10180
** right-hand operand is not known, then *V is set to a NULL pointer.
10181
** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if
10182
** and only if *V is set to a value.  ^The sqlite3_vtab_rhs_value(P,J,V)
10183
** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th
10184
** constraint is not available.  ^The sqlite3_vtab_rhs_value() interface
10185
** can return an result code other than SQLITE_OK or SQLITE_NOTFOUND if
10186
** something goes wrong.
10187
**
10188
** The sqlite3_vtab_rhs_value() interface is usually only successful if
10189
** the right-hand operand of a constraint is a literal value in the original
10190
** SQL statement.  If the right-hand operand is an expression or a reference
10191
** to some other column or a [host parameter], then sqlite3_vtab_rhs_value()
10192
** will probably return [SQLITE_NOTFOUND].
10193
**
10194
** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and
10195
** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand.  For such
10196
** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^
10197
**
10198
** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value
10199
** and remains valid for the duration of the xBestIndex method call.
10200
** ^When xBestIndex returns, the sqlite3_value object returned by
10201
** sqlite3_vtab_rhs_value() is automatically deallocated.
10202
**
10203
** The "_rhs_" in the name of this routine is an abbreviation for
10204
** "Right-Hand Side".
10205
*/
10206
SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal);
10207
10208
/*
10209
** CAPI3REF: Conflict resolution modes
10210
** KEYWORDS: {conflict resolution mode}
10211
**
10212
** These constants are returned by [sqlite3_vtab_on_conflict()] to
10213
** inform a [virtual table] implementation what the [ON CONFLICT] mode
10214
** is for the SQL statement being evaluated.
10215
**
10216
** Note that the [SQLITE_IGNORE] constant is also used as a potential
10217
** return value from the [sqlite3_set_authorizer()] callback and that
10218
** [SQLITE_ABORT] is also a [result code].
10219
*/
10220
#define SQLITE_ROLLBACK 1
10221
/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
10222
#define SQLITE_FAIL     3
10223
/* #define SQLITE_ABORT 4  // Also an error code */
10224
#define SQLITE_REPLACE  5
10225
10226
/*
10227
** CAPI3REF: Prepared Statement Scan Status Opcodes
10228
** KEYWORDS: {scanstatus options}
10229
**
10230
** The following constants can be used for the T parameter to the
10231
** [sqlite3_stmt_scanstatus(S,X,T,V)] interface.  Each constant designates a
10232
** different metric for sqlite3_stmt_scanstatus() to return.
10233
**
10234
** When the value returned to V is a string, space to hold that string is
10235
** managed by the prepared statement S and will be automatically freed when
10236
** S is finalized.
10237
**
10238
** Not all values are available for all query elements. When a value is
10239
** not available, the output variable is set to -1 if the value is numeric,
10240
** or to NULL if it is a string (SQLITE_SCANSTAT_NAME).
10241
**
10242
** <dl>
10243
** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
10244
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be
10245
** set to the total number of times that the X-th loop has run.</dd>
10246
**
10247
** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
10248
** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set
10249
** to the total number of rows examined by all iterations of the X-th loop.</dd>
10250
**
10251
** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
10252
** <dd>^The "double" variable pointed to by the V parameter will be set to the
10253
** query planner's estimate for the average number of rows output from each
10254
** iteration of the X-th loop.  If the query planner's estimates was accurate,
10255
** then this value will approximate the quotient NVISIT/NLOOP and the
10256
** product of this value for all prior loops with the same SELECTID will
10257
** be the NLOOP value for the current loop.
10258
**
10259
** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
10260
** <dd>^The "const char *" variable pointed to by the V parameter will be set
10261
** to a zero-terminated UTF-8 string containing the name of the index or table
10262
** used for the X-th loop.
10263
**
10264
** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
10265
** <dd>^The "const char *" variable pointed to by the V parameter will be set
10266
** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
10267
** description for the X-th loop.
10268
**
10269
** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECTID</dt>
10270
** <dd>^The "int" variable pointed to by the V parameter will be set to the
10271
** id for the X-th query plan element. The id value is unique within the
10272
** statement. The select-id is the same value as is output in the first
10273
** column of an [EXPLAIN QUERY PLAN] query.
10274
**
10275
** [[SQLITE_SCANSTAT_PARENTID]] <dt>SQLITE_SCANSTAT_PARENTID</dt>
10276
** <dd>The "int" variable pointed to by the V parameter will be set to the
10277
** the id of the parent of the current query element, if applicable, or
10278
** to zero if the query element has no parent. This is the same value as
10279
** returned in the second column of an [EXPLAIN QUERY PLAN] query.
10280
**
10281
** [[SQLITE_SCANSTAT_NCYCLE]] <dt>SQLITE_SCANSTAT_NCYCLE</dt>
10282
** <dd>The sqlite3_int64 output value is set to the number of cycles,
10283
** according to the processor time-stamp counter, that elapsed while the
10284
** query element was being processed. This value is not available for
10285
** all query elements - if it is unavailable the output variable is
10286
** set to -1.
10287
** </dl>
10288
*/
10289
#define SQLITE_SCANSTAT_NLOOP    0
10290
#define SQLITE_SCANSTAT_NVISIT   1
10291
#define SQLITE_SCANSTAT_EST      2
10292
#define SQLITE_SCANSTAT_NAME     3
10293
#define SQLITE_SCANSTAT_EXPLAIN  4
10294
#define SQLITE_SCANSTAT_SELECTID 5
10295
#define SQLITE_SCANSTAT_PARENTID 6
10296
#define SQLITE_SCANSTAT_NCYCLE   7
10297
10298
/*
10299
** CAPI3REF: Prepared Statement Scan Status
10300
** METHOD: sqlite3_stmt
10301
**
10302
** These interfaces return information about the predicted and measured
10303
** performance for pStmt.  Advanced applications can use this
10304
** interface to compare the predicted and the measured performance and
10305
** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
10306
**
10307
** Since this interface is expected to be rarely used, it is only
10308
** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
10309
** compile-time option.
10310
**
10311
** The "iScanStatusOp" parameter determines which status information to return.
10312
** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
10313
** of this interface is undefined. ^The requested measurement is written into
10314
** a variable pointed to by the "pOut" parameter.
10315
**
10316
** The "flags" parameter must be passed a mask of flags. At present only
10317
** one flag is defined - SQLITE_SCANSTAT_COMPLEX. If SQLITE_SCANSTAT_COMPLEX
10318
** is specified, then status information is available for all elements
10319
** of a query plan that are reported by "EXPLAIN QUERY PLAN" output. If
10320
** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements
10321
** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of
10322
** the EXPLAIN QUERY PLAN output) are available. Invoking API
10323
** sqlite3_stmt_scanstatus() is equivalent to calling
10324
** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter.
10325
**
10326
** Parameter "idx" identifies the specific query element to retrieve statistics
10327
** for. Query elements are numbered starting from zero. A value of -1 may be
10328
** to query for statistics regarding the entire query. ^If idx is out of range
10329
** - less than -1 or greater than or equal to the total number of query
10330
** elements used to implement the statement - a non-zero value is returned and
10331
** the variable that pOut points to is unchanged.
10332
**
10333
** See also: [sqlite3_stmt_scanstatus_reset()]
10334
*/
10335
SQLITE_API int sqlite3_stmt_scanstatus(
10336
  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
10337
  int idx,                  /* Index of loop to report on */
10338
  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
10339
  void *pOut                /* Result written here */
10340
);
10341
SQLITE_API int sqlite3_stmt_scanstatus_v2(
10342
  sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
10343
  int idx,                  /* Index of loop to report on */
10344
  int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
10345
  int flags,                /* Mask of flags defined below */
10346
  void *pOut                /* Result written here */
10347
);
10348
10349
/*
10350
** CAPI3REF: Prepared Statement Scan Status
10351
** KEYWORDS: {scan status flags}
10352
*/
10353
#define SQLITE_SCANSTAT_COMPLEX 0x0001
10354
10355
/*
10356
** CAPI3REF: Zero Scan-Status Counters
10357
** METHOD: sqlite3_stmt
10358
**
10359
** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
10360
**
10361
** This API is only available if the library is built with pre-processor
10362
** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
10363
*/
10364
SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
10365
10366
/*
10367
** CAPI3REF: Flush caches to disk mid-transaction
10368
** METHOD: sqlite3
10369
**
10370
** ^If a write-transaction is open on [database connection] D when the
10371
** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
10372
** pages in the pager-cache that are not currently in use are written out
10373
** to disk. A dirty page may be in use if a database cursor created by an
10374
** active SQL statement is reading from it, or if it is page 1 of a database
10375
** file (page 1 is always "in use").  ^The [sqlite3_db_cacheflush(D)]
10376
** interface flushes caches for all schemas - "main", "temp", and
10377
** any [attached] databases.
10378
**
10379
** ^If this function needs to obtain extra database locks before dirty pages
10380
** can be flushed to disk, it does so. ^If those locks cannot be obtained
10381
** immediately and there is a busy-handler callback configured, it is invoked
10382
** in the usual manner. ^If the required lock still cannot be obtained, then
10383
** the database is skipped and an attempt made to flush any dirty pages
10384
** belonging to the next (if any) database. ^If any databases are skipped
10385
** because locks cannot be obtained, but no other error occurs, this
10386
** function returns SQLITE_BUSY.
10387
**
10388
** ^If any other error occurs while flushing dirty pages to disk (for
10389
** example an IO error or out-of-memory condition), then processing is
10390
** abandoned and an SQLite [error code] is returned to the caller immediately.
10391
**
10392
** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
10393
**
10394
** ^This function does not set the database handle error code or message
10395
** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
10396
*/
10397
SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
10398
10399
/*
10400
** CAPI3REF: The pre-update hook.
10401
** METHOD: sqlite3
10402
**
10403
** ^These interfaces are only available if SQLite is compiled using the
10404
** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
10405
**
10406
** ^The [sqlite3_preupdate_hook()] interface registers a callback function
10407
** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
10408
** on a database table.
10409
** ^At most one preupdate hook may be registered at a time on a single
10410
** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
10411
** the previous setting.
10412
** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
10413
** with a NULL pointer as the second parameter.
10414
** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
10415
** the first parameter to callbacks.
10416
**
10417
** ^The preupdate hook only fires for changes to real database tables; the
10418
** preupdate hook is not invoked for changes to [virtual tables] or to
10419
** system tables like sqlite_sequence or sqlite_stat1.
10420
**
10421
** ^The second parameter to the preupdate callback is a pointer to
10422
** the [database connection] that registered the preupdate hook.
10423
** ^The third parameter to the preupdate callback is one of the constants
10424
** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
10425
** kind of update operation that is about to occur.
10426
** ^(The fourth parameter to the preupdate callback is the name of the
10427
** database within the database connection that is being modified.  This
10428
** will be "main" for the main database or "temp" for TEMP tables or
10429
** the name given after the AS keyword in the [ATTACH] statement for attached
10430
** databases.)^
10431
** ^The fifth parameter to the preupdate callback is the name of the
10432
** table that is being modified.
10433
**
10434
** For an UPDATE or DELETE operation on a [rowid table], the sixth
10435
** parameter passed to the preupdate callback is the initial [rowid] of the
10436
** row being modified or deleted. For an INSERT operation on a rowid table,
10437
** or any operation on a WITHOUT ROWID table, the value of the sixth
10438
** parameter is undefined. For an INSERT or UPDATE on a rowid table the
10439
** seventh parameter is the final rowid value of the row being inserted
10440
** or updated. The value of the seventh parameter passed to the callback
10441
** function is not defined for operations on WITHOUT ROWID tables, or for
10442
** DELETE operations on rowid tables.
10443
**
10444
** ^The sqlite3_preupdate_hook(D,C,P) function returns the P argument from
10445
** the previous call on the same [database connection] D, or NULL for
10446
** the first call on D.
10447
**
10448
** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
10449
** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
10450
** provide additional information about a preupdate event. These routines
10451
** may only be called from within a preupdate callback.  Invoking any of
10452
** these routines from outside of a preupdate callback or with a
10453
** [database connection] pointer that is different from the one supplied
10454
** to the preupdate callback results in undefined and probably undesirable
10455
** behavior.
10456
**
10457
** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
10458
** in the row that is being inserted, updated, or deleted.
10459
**
10460
** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
10461
** a [protected sqlite3_value] that contains the value of the Nth column of
10462
** the table row before it is updated.  The N parameter must be between 0
10463
** and one less than the number of columns or the behavior will be
10464
** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
10465
** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
10466
** behavior is undefined.  The [sqlite3_value] that P points to
10467
** will be destroyed when the preupdate callback returns.
10468
**
10469
** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
10470
** a [protected sqlite3_value] that contains the value of the Nth column of
10471
** the table row after it is updated.  The N parameter must be between 0
10472
** and one less than the number of columns or the behavior will be
10473
** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
10474
** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
10475
** behavior is undefined.  The [sqlite3_value] that P points to
10476
** will be destroyed when the preupdate callback returns.
10477
**
10478
** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
10479
** callback was invoked as a result of a direct insert, update, or delete
10480
** operation; or 1 for inserts, updates, or deletes invoked by top-level
10481
** triggers; or 2 for changes resulting from triggers called by top-level
10482
** triggers; and so forth.
10483
**
10484
** When the [sqlite3_blob_write()] API is used to update a blob column,
10485
** the pre-update hook is invoked with SQLITE_DELETE. This is because the
10486
** in this case the new values are not available. In this case, when a
10487
** callback made with op==SQLITE_DELETE is actually a write using the
10488
** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns
10489
** the index of the column being written. In other cases, where the
10490
** pre-update hook is being invoked for some other reason, including a
10491
** regular DELETE, sqlite3_preupdate_blobwrite() returns -1.
10492
**
10493
** See also:  [sqlite3_update_hook()]
10494
*/
10495
#if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
10496
SQLITE_API void *sqlite3_preupdate_hook(
10497
  sqlite3 *db,
10498
  void(*xPreUpdate)(
10499
    void *pCtx,                   /* Copy of third arg to preupdate_hook() */
10500
    sqlite3 *db,                  /* Database handle */
10501
    int op,                       /* SQLITE_UPDATE, DELETE or INSERT */
10502
    char const *zDb,              /* Database name */
10503
    char const *zName,            /* Table name */
10504
    sqlite3_int64 iKey1,          /* Rowid of row about to be deleted/updated */
10505
    sqlite3_int64 iKey2           /* New rowid value (for a rowid UPDATE) */
10506
  ),
10507
  void*
10508
);
10509
SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
10510
SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
10511
SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
10512
SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
10513
SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *);
10514
#endif
10515
10516
/*
10517
** CAPI3REF: Low-level system error code
10518
** METHOD: sqlite3
10519
**
10520
** ^Attempt to return the underlying operating system error code or error
10521
** number that caused the most recent I/O error or failure to open a file.
10522
** The return value is OS-dependent.  For example, on unix systems, after
10523
** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
10524
** called to get back the underlying "errno" that caused the problem, such
10525
** as ENOSPC, EAUTH, EISDIR, and so forth.
10526
*/
10527
SQLITE_API int sqlite3_system_errno(sqlite3*);
10528
10529
/*
10530
** CAPI3REF: Database Snapshot
10531
** KEYWORDS: {snapshot} {sqlite3_snapshot}
10532
**
10533
** An instance of the snapshot object records the state of a [WAL mode]
10534
** database for some specific point in history.
10535
**
10536
** In [WAL mode], multiple [database connections] that are open on the
10537
** same database file can each be reading a different historical version
10538
** of the database file.  When a [database connection] begins a read
10539
** transaction, that connection sees an unchanging copy of the database
10540
** as it existed for the point in time when the transaction first started.
10541
** Subsequent changes to the database from other connections are not seen
10542
** by the reader until a new read transaction is started.
10543
**
10544
** The sqlite3_snapshot object records state information about an historical
10545
** version of the database file so that it is possible to later open a new read
10546
** transaction that sees that historical version of the database rather than
10547
** the most recent version.
10548
*/
10549
typedef struct sqlite3_snapshot {
10550
  unsigned char hidden[48];
10551
} sqlite3_snapshot;
10552
10553
/*
10554
** CAPI3REF: Record A Database Snapshot
10555
** CONSTRUCTOR: sqlite3_snapshot
10556
**
10557
** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
10558
** new [sqlite3_snapshot] object that records the current state of
10559
** schema S in database connection D.  ^On success, the
10560
** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
10561
** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
10562
** If there is not already a read-transaction open on schema S when
10563
** this function is called, one is opened automatically.
10564
**
10565
** If a read-transaction is opened by this function, then it is guaranteed
10566
** that the returned snapshot object may not be invalidated by a database
10567
** writer or checkpointer until after the read-transaction is closed. This
10568
** is not guaranteed if a read-transaction is already open when this
10569
** function is called. In that case, any subsequent write or checkpoint
10570
** operation on the database may invalidate the returned snapshot handle,
10571
** even while the read-transaction remains open.
10572
**
10573
** The following must be true for this function to succeed. If any of
10574
** the following statements are false when sqlite3_snapshot_get() is
10575
** called, SQLITE_ERROR is returned. The final value of *P is undefined
10576
** in this case.
10577
**
10578
** <ul>
10579
**   <li> The database handle must not be in [autocommit mode].
10580
**
10581
**   <li> Schema S of [database connection] D must be a [WAL mode] database.
10582
**
10583
**   <li> There must not be a write transaction open on schema S of database
10584
**        connection D.
10585
**
10586
**   <li> One or more transactions must have been written to the current wal
10587
**        file since it was created on disk (by any connection). This means
10588
**        that a snapshot cannot be taken on a wal mode database with no wal
10589
**        file immediately after it is first opened. At least one transaction
10590
**        must be written to it first.
10591
** </ul>
10592
**
10593
** This function may also return SQLITE_NOMEM.  If it is called with the
10594
** database handle in autocommit mode but fails for some other reason,
10595
** whether or not a read transaction is opened on schema S is undefined.
10596
**
10597
** The [sqlite3_snapshot] object returned from a successful call to
10598
** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
10599
** to avoid a memory leak.
10600
**
10601
** The [sqlite3_snapshot_get()] interface is only available when the
10602
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10603
*/
10604
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
10605
  sqlite3 *db,
10606
  const char *zSchema,
10607
  sqlite3_snapshot **ppSnapshot
10608
);
10609
10610
/*
10611
** CAPI3REF: Start a read transaction on an historical snapshot
10612
** METHOD: sqlite3_snapshot
10613
**
10614
** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read
10615
** transaction or upgrades an existing one for schema S of
10616
** [database connection] D such that the read transaction refers to
10617
** historical [snapshot] P, rather than the most recent change to the
10618
** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK
10619
** on success or an appropriate [error code] if it fails.
10620
**
10621
** ^In order to succeed, the database connection must not be in
10622
** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there
10623
** is already a read transaction open on schema S, then the database handle
10624
** must have no active statements (SELECT statements that have been passed
10625
** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()).
10626
** SQLITE_ERROR is returned if either of these conditions is violated, or
10627
** if schema S does not exist, or if the snapshot object is invalid.
10628
**
10629
** ^A call to sqlite3_snapshot_open() will fail to open if the specified
10630
** snapshot has been overwritten by a [checkpoint]. In this case
10631
** SQLITE_ERROR_SNAPSHOT is returned.
10632
**
10633
** If there is already a read transaction open when this function is
10634
** invoked, then the same read transaction remains open (on the same
10635
** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT
10636
** is returned. If another error code - for example SQLITE_PROTOCOL or an
10637
** SQLITE_IOERR error code - is returned, then the final state of the
10638
** read transaction is undefined. If SQLITE_OK is returned, then the
10639
** read transaction is now open on database snapshot P.
10640
**
10641
** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
10642
** database connection D does not know that the database file for
10643
** schema S is in [WAL mode].  A database connection might not know
10644
** that the database file is in [WAL mode] if there has been no prior
10645
** I/O on that database connection, or if the database entered [WAL mode]
10646
** after the most recent I/O on the database connection.)^
10647
** (Hint: Run "[PRAGMA application_id]" against a newly opened
10648
** database connection in order to make it ready to use snapshots.)
10649
**
10650
** The [sqlite3_snapshot_open()] interface is only available when the
10651
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10652
*/
10653
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
10654
  sqlite3 *db,
10655
  const char *zSchema,
10656
  sqlite3_snapshot *pSnapshot
10657
);
10658
10659
/*
10660
** CAPI3REF: Destroy a snapshot
10661
** DESTRUCTOR: sqlite3_snapshot
10662
**
10663
** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
10664
** The application must eventually free every [sqlite3_snapshot] object
10665
** using this routine to avoid a memory leak.
10666
**
10667
** The [sqlite3_snapshot_free()] interface is only available when the
10668
** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
10669
*/
10670
SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);
10671
10672
/*
10673
** CAPI3REF: Compare the ages of two snapshot handles.
10674
** METHOD: sqlite3_snapshot
10675
**
10676
** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
10677
** of two valid snapshot handles.
10678
**
10679
** If the two snapshot handles are not associated with the same database
10680
** file, the result of the comparison is undefined.
10681
**
10682
** Additionally, the result of the comparison is only valid if both of the
10683
** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
10684
** last time the wal file was deleted. The wal file is deleted when the
10685
** database is changed back to rollback mode or when the number of database
10686
** clients drops to zero. If either snapshot handle was obtained before the
10687
** wal file was last deleted, the value returned by this function
10688
** is undefined.
10689
**
10690
** Otherwise, this API returns a negative value if P1 refers to an older
10691
** snapshot than P2, zero if the two handles refer to the same database
10692
** snapshot, and a positive value if P1 is a newer snapshot than P2.
10693
**
10694
** This interface is only available if SQLite is compiled with the
10695
** [SQLITE_ENABLE_SNAPSHOT] option.
10696
*/
10697
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
10698
  sqlite3_snapshot *p1,
10699
  sqlite3_snapshot *p2
10700
);
10701
10702
/*
10703
** CAPI3REF: Recover snapshots from a wal file
10704
** METHOD: sqlite3_snapshot
10705
**
10706
** If a [WAL file] remains on disk after all database connections close
10707
** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control]
10708
** or because the last process to have the database opened exited without
10709
** calling [sqlite3_close()]) and a new connection is subsequently opened
10710
** on that database and [WAL file], the [sqlite3_snapshot_open()] interface
10711
** will only be able to open the last transaction added to the WAL file
10712
** even though the WAL file contains other valid transactions.
10713
**
10714
** This function attempts to scan the WAL file associated with database zDb
10715
** of database handle db and make all valid snapshots available to
10716
** sqlite3_snapshot_open(). It is an error if there is already a read
10717
** transaction open on the database, or if the database is not a WAL mode
10718
** database.
10719
**
10720
** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
10721
**
10722
** This interface is only available if SQLite is compiled with the
10723
** [SQLITE_ENABLE_SNAPSHOT] option.
10724
*/
10725
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
10726
10727
/*
10728
** CAPI3REF: Serialize a database
10729
**
10730
** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory
10731
** that is a serialization of the S database on [database connection] D.
10732
** If P is not a NULL pointer, then the size of the database in bytes
10733
** is written into *P.
10734
**
10735
** For an ordinary on-disk database file, the serialization is just a
10736
** copy of the disk file.  For an in-memory database or a "TEMP" database,
10737
** the serialization is the same sequence of bytes which would be written
10738
** to disk if that database where backed up to disk.
10739
**
10740
** The usual case is that sqlite3_serialize() copies the serialization of
10741
** the database into memory obtained from [sqlite3_malloc64()] and returns
10742
** a pointer to that memory.  The caller is responsible for freeing the
10743
** returned value to avoid a memory leak.  However, if the F argument
10744
** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations
10745
** are made, and the sqlite3_serialize() function will return a pointer
10746
** to the contiguous memory representation of the database that SQLite
10747
** is currently using for that database, or NULL if the no such contiguous
10748
** memory representation of the database exists.  A contiguous memory
10749
** representation of the database will usually only exist if there has
10750
** been a prior call to [sqlite3_deserialize(D,S,...)] with the same
10751
** values of D and S.
10752
** The size of the database is written into *P even if the
10753
** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy
10754
** of the database exists.
10755
**
10756
** After the call, if the SQLITE_SERIALIZE_NOCOPY bit had been set,
10757
** the returned buffer content will remain accessible and unchanged
10758
** until either the next write operation on the connection or when
10759
** the connection is closed, and applications must not modify the
10760
** buffer. If the bit had been clear, the returned buffer will not
10761
** be accessed by SQLite after the call.
10762
**
10763
** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the
10764
** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory
10765
** allocation error occurs.
10766
**
10767
** This interface is omitted if SQLite is compiled with the
10768
** [SQLITE_OMIT_DESERIALIZE] option.
10769
*/
10770
SQLITE_API unsigned char *sqlite3_serialize(
10771
  sqlite3 *db,           /* The database connection */
10772
  const char *zSchema,   /* Which DB to serialize. ex: "main", "temp", ... */
10773
  sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */
10774
  unsigned int mFlags    /* Zero or more SQLITE_SERIALIZE_* flags */
10775
);
10776
10777
/*
10778
** CAPI3REF: Flags for sqlite3_serialize
10779
**
10780
** Zero or more of the following constants can be OR-ed together for
10781
** the F argument to [sqlite3_serialize(D,S,P,F)].
10782
**
10783
** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return
10784
** a pointer to contiguous in-memory database that it is currently using,
10785
** without making a copy of the database.  If SQLite is not currently using
10786
** a contiguous in-memory database, then this option causes
10787
** [sqlite3_serialize()] to return a NULL pointer.  SQLite will only be
10788
** using a contiguous in-memory database if it has been initialized by a
10789
** prior call to [sqlite3_deserialize()].
10790
*/
10791
#define SQLITE_SERIALIZE_NOCOPY 0x001   /* Do no memory allocations */
10792
10793
/*
10794
** CAPI3REF: Deserialize a database
10795
**
10796
** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the
10797
** [database connection] D to disconnect from database S and then
10798
** reopen S as an in-memory database based on the serialization contained
10799
** in P.  The serialized database P is N bytes in size.  M is the size of
10800
** the buffer P, which might be larger than N.  If M is larger than N, and
10801
** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is
10802
** permitted to add content to the in-memory database as long as the total
10803
** size does not exceed M bytes.
10804
**
10805
** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will
10806
** invoke sqlite3_free() on the serialization buffer when the database
10807
** connection closes.  If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then
10808
** SQLite will try to increase the buffer size using sqlite3_realloc64()
10809
** if writes on the database cause it to grow larger than M bytes.
10810
**
10811
** Applications must not modify the buffer P or invalidate it before
10812
** the database connection D is closed.
10813
**
10814
** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the
10815
** database is currently in a read transaction or is involved in a backup
10816
** operation.
10817
**
10818
** It is not possible to deserialized into the TEMP database.  If the
10819
** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the
10820
** function returns SQLITE_ERROR.
10821
**
10822
** The deserialized database should not be in [WAL mode].  If the database
10823
** is in WAL mode, then any attempt to use the database file will result
10824
** in an [SQLITE_CANTOPEN] error.  The application can set the
10825
** [file format version numbers] (bytes 18 and 19) of the input database P
10826
** to 0x01 prior to invoking sqlite3_deserialize(D,S,P,N,M,F) to force the
10827
** database file into rollback mode and work around this limitation.
10828
**
10829
** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the
10830
** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then
10831
** [sqlite3_free()] is invoked on argument P prior to returning.
10832
**
10833
** This interface is omitted if SQLite is compiled with the
10834
** [SQLITE_OMIT_DESERIALIZE] option.
10835
*/
10836
SQLITE_API int sqlite3_deserialize(
10837
  sqlite3 *db,            /* The database connection */
10838
  const char *zSchema,    /* Which DB to reopen with the deserialization */
10839
  unsigned char *pData,   /* The serialized database content */
10840
  sqlite3_int64 szDb,     /* Number bytes in the deserialization */
10841
  sqlite3_int64 szBuf,    /* Total size of buffer pData[] */
10842
  unsigned mFlags         /* Zero or more SQLITE_DESERIALIZE_* flags */
10843
);
10844
10845
/*
10846
** CAPI3REF: Flags for sqlite3_deserialize()
10847
**
10848
** The following are allowed values for 6th argument (the F argument) to
10849
** the [sqlite3_deserialize(D,S,P,N,M,F)] interface.
10850
**
10851
** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization
10852
** in the P argument is held in memory obtained from [sqlite3_malloc64()]
10853
** and that SQLite should take ownership of this memory and automatically
10854
** free it when it has finished using it.  Without this flag, the caller
10855
** is responsible for freeing any dynamically allocated memory.
10856
**
10857
** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to
10858
** grow the size of the database using calls to [sqlite3_realloc64()].  This
10859
** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used.
10860
** Without this flag, the deserialized database cannot increase in size beyond
10861
** the number of bytes specified by the M parameter.
10862
**
10863
** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database
10864
** should be treated as read-only.
10865
*/
10866
#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */
10867
#define SQLITE_DESERIALIZE_RESIZEABLE  2 /* Resize using sqlite3_realloc64() */
10868
#define SQLITE_DESERIALIZE_READONLY    4 /* Database is read-only */
10869
10870
/*
10871
** Undo the hack that converts floating point types to integer for
10872
** builds on processors without floating point support.
10873
*/
10874
#ifdef SQLITE_OMIT_FLOATING_POINT
10875
# undef double
10876
#endif
10877
10878
#if defined(__wasi__)
10879
# undef SQLITE_WASI
10880
# define SQLITE_WASI 1
10881
# ifndef SQLITE_OMIT_LOAD_EXTENSION
10882
#  define SQLITE_OMIT_LOAD_EXTENSION
10883
# endif
10884
# ifndef SQLITE_THREADSAFE
10885
#  define SQLITE_THREADSAFE 0
10886
# endif
10887
#endif
10888
10889
#ifdef __cplusplus
10890
}  /* End of the 'extern "C"' block */
10891
#endif
10892
#endif /* SQLITE3_H */
10893
10894
/******** Begin file sqlite3rtree.h *********/
10895
/*
10896
** 2010 August 30
10897
**
10898
** The author disclaims copyright to this source code.  In place of
10899
** a legal notice, here is a blessing:
10900
**
10901
**    May you do good and not evil.
10902
**    May you find forgiveness for yourself and forgive others.
10903
**    May you share freely, never taking more than you give.
10904
**
10905
*************************************************************************
10906
*/
10907
10908
#ifndef _SQLITE3RTREE_H_
10909
#define _SQLITE3RTREE_H_
10910
10911
10912
#ifdef __cplusplus
10913
extern "C" {
10914
#endif
10915
10916
typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
10917
typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
10918
10919
/* The double-precision datatype used by RTree depends on the
10920
** SQLITE_RTREE_INT_ONLY compile-time option.
10921
*/
10922
#ifdef SQLITE_RTREE_INT_ONLY
10923
  typedef sqlite3_int64 sqlite3_rtree_dbl;
10924
#else
10925
  typedef double sqlite3_rtree_dbl;
10926
#endif
10927
10928
/*
10929
** Register a geometry callback named zGeom that can be used as part of an
10930
** R-Tree geometry query as follows:
10931
**
10932
**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
10933
*/
10934
SQLITE_API int sqlite3_rtree_geometry_callback(
10935
  sqlite3 *db,
10936
  const char *zGeom,
10937
  int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
10938
  void *pContext
10939
);
10940
10941
10942
/*
10943
** A pointer to a structure of the following type is passed as the first
10944
** argument to callbacks registered using rtree_geometry_callback().
10945
*/
10946
struct sqlite3_rtree_geometry {
10947
  void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
10948
  int nParam;                     /* Size of array aParam[] */
10949
  sqlite3_rtree_dbl *aParam;      /* Parameters passed to SQL geom function */
10950
  void *pUser;                    /* Callback implementation user data */
10951
  void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
10952
};
10953
10954
/*
10955
** Register a 2nd-generation geometry callback named zScore that can be
10956
** used as part of an R-Tree geometry query as follows:
10957
**
10958
**   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
10959
*/
10960
SQLITE_API int sqlite3_rtree_query_callback(
10961
  sqlite3 *db,
10962
  const char *zQueryFunc,
10963
  int (*xQueryFunc)(sqlite3_rtree_query_info*),
10964
  void *pContext,
10965
  void (*xDestructor)(void*)
10966
);
10967
10968
10969
/*
10970
** A pointer to a structure of the following type is passed as the
10971
** argument to scored geometry callback registered using
10972
** sqlite3_rtree_query_callback().
10973
**
10974
** Note that the first 5 fields of this structure are identical to
10975
** sqlite3_rtree_geometry.  This structure is a subclass of
10976
** sqlite3_rtree_geometry.
10977
*/
10978
struct sqlite3_rtree_query_info {
10979
  void *pContext;                   /* pContext from when function registered */
10980
  int nParam;                       /* Number of function parameters */
10981
  sqlite3_rtree_dbl *aParam;        /* value of function parameters */
10982
  void *pUser;                      /* callback can use this, if desired */
10983
  void (*xDelUser)(void*);          /* function to free pUser */
10984
  sqlite3_rtree_dbl *aCoord;        /* Coordinates of node or entry to check */
10985
  unsigned int *anQueue;            /* Number of pending entries in the queue */
10986
  int nCoord;                       /* Number of coordinates */
10987
  int iLevel;                       /* Level of current node or entry */
10988
  int mxLevel;                      /* The largest iLevel value in the tree */
10989
  sqlite3_int64 iRowid;             /* Rowid for current entry */
10990
  sqlite3_rtree_dbl rParentScore;   /* Score of parent node */
10991
  int eParentWithin;                /* Visibility of parent node */
10992
  int eWithin;                      /* OUT: Visibility */
10993
  sqlite3_rtree_dbl rScore;         /* OUT: Write the score here */
10994
  /* The following fields are only available in 3.8.11 and later */
10995
  sqlite3_value **apSqlParam;       /* Original SQL values of parameters */
10996
};
10997
10998
/*
10999
** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
11000
*/
11001
#define NOT_WITHIN       0   /* Object completely outside of query region */
11002
#define PARTLY_WITHIN    1   /* Object partially overlaps query region */
11003
#define FULLY_WITHIN     2   /* Object fully contained within query region */
11004
11005
11006
#ifdef __cplusplus
11007
}  /* end of the 'extern "C"' block */
11008
#endif
11009
11010
#endif  /* ifndef _SQLITE3RTREE_H_ */
11011
11012
/******** End of sqlite3rtree.h *********/
11013
/******** Begin file sqlite3session.h *********/
11014
11015
#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
11016
#define __SQLITESESSION_H_ 1
11017
11018
/*
11019
** Make sure we can call this stuff from C++.
11020
*/
11021
#ifdef __cplusplus
11022
extern "C" {
11023
#endif
11024
11025
11026
/*
11027
** CAPI3REF: Session Object Handle
11028
**
11029
** An instance of this object is a [session] that can be used to
11030
** record changes to a database.
11031
*/
11032
typedef struct sqlite3_session sqlite3_session;
11033
11034
/*
11035
** CAPI3REF: Changeset Iterator Handle
11036
**
11037
** An instance of this object acts as a cursor for iterating
11038
** over the elements of a [changeset] or [patchset].
11039
*/
11040
typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
11041
11042
/*
11043
** CAPI3REF: Create A New Session Object
11044
** CONSTRUCTOR: sqlite3_session
11045
**
11046
** Create a new session object attached to database handle db. If successful,
11047
** a pointer to the new object is written to *ppSession and SQLITE_OK is
11048
** returned. If an error occurs, *ppSession is set to NULL and an SQLite
11049
** error code (e.g. SQLITE_NOMEM) is returned.
11050
**
11051
** It is possible to create multiple session objects attached to a single
11052
** database handle.
11053
**
11054
** Session objects created using this function should be deleted using the
11055
** [sqlite3session_delete()] function before the database handle that they
11056
** are attached to is itself closed. If the database handle is closed before
11057
** the session object is deleted, then the results of calling any session
11058
** module function, including [sqlite3session_delete()] on the session object
11059
** are undefined.
11060
**
11061
** Because the session module uses the [sqlite3_preupdate_hook()] API, it
11062
** is not possible for an application to register a pre-update hook on a
11063
** database handle that has one or more session objects attached. Nor is
11064
** it possible to create a session object attached to a database handle for
11065
** which a pre-update hook is already defined. The results of attempting
11066
** either of these things are undefined.
11067
**
11068
** The session object will be used to create changesets for tables in
11069
** database zDb, where zDb is either "main", or "temp", or the name of an
11070
** attached database. It is not an error if database zDb is not attached
11071
** to the database when the session object is created.
11072
*/
11073
SQLITE_API int sqlite3session_create(
11074
  sqlite3 *db,                    /* Database handle */
11075
  const char *zDb,                /* Name of db (e.g. "main") */
11076
  sqlite3_session **ppSession     /* OUT: New session object */
11077
);
11078
11079
/*
11080
** CAPI3REF: Delete A Session Object
11081
** DESTRUCTOR: sqlite3_session
11082
**
11083
** Delete a session object previously allocated using
11084
** [sqlite3session_create()]. Once a session object has been deleted, the
11085
** results of attempting to use pSession with any other session module
11086
** function are undefined.
11087
**
11088
** Session objects must be deleted before the database handle to which they
11089
** are attached is closed. Refer to the documentation for
11090
** [sqlite3session_create()] for details.
11091
*/
11092
SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
11093
11094
/*
11095
** CAPI3REF: Configure a Session Object
11096
** METHOD: sqlite3_session
11097
**
11098
** This method is used to configure a session object after it has been
11099
** created. At present the only valid values for the second parameter are
11100
** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID].
11101
**
11102
*/
11103
SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg);
11104
11105
/*
11106
** CAPI3REF: Options for sqlite3session_object_config
11107
**
11108
** The following values may passed as the the 2nd parameter to
11109
** sqlite3session_object_config().
11110
**
11111
** <dt>SQLITE_SESSION_OBJCONFIG_SIZE <dd>
11112
**   This option is used to set, clear or query the flag that enables
11113
**   the [sqlite3session_changeset_size()] API. Because it imposes some
11114
**   computational overhead, this API is disabled by default. Argument
11115
**   pArg must point to a value of type (int). If the value is initially
11116
**   0, then the sqlite3session_changeset_size() API is disabled. If it
11117
**   is greater than 0, then the same API is enabled. Or, if the initial
11118
**   value is less than zero, no change is made. In all cases the (int)
11119
**   variable is set to 1 if the sqlite3session_changeset_size() API is
11120
**   enabled following the current call, or 0 otherwise.
11121
**
11122
**   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
11123
**   the first table has been attached to the session object.
11124
**
11125
** <dt>SQLITE_SESSION_OBJCONFIG_ROWID <dd>
11126
**   This option is used to set, clear or query the flag that enables
11127
**   collection of data for tables with no explicit PRIMARY KEY.
11128
**
11129
**   Normally, tables with no explicit PRIMARY KEY are simply ignored
11130
**   by the sessions module. However, if this flag is set, it behaves
11131
**   as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted
11132
**   as their leftmost columns.
11133
**
11134
**   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
11135
**   the first table has been attached to the session object.
11136
*/
11137
#define SQLITE_SESSION_OBJCONFIG_SIZE  1
11138
#define SQLITE_SESSION_OBJCONFIG_ROWID 2
11139
11140
/*
11141
** CAPI3REF: Enable Or Disable A Session Object
11142
** METHOD: sqlite3_session
11143
**
11144
** Enable or disable the recording of changes by a session object. When
11145
** enabled, a session object records changes made to the database. When
11146
** disabled - it does not. A newly created session object is enabled.
11147
** Refer to the documentation for [sqlite3session_changeset()] for further
11148
** details regarding how enabling and disabling a session object affects
11149
** the eventual changesets.
11150
**
11151
** Passing zero to this function disables the session. Passing a value
11152
** greater than zero enables it. Passing a value less than zero is a
11153
** no-op, and may be used to query the current state of the session.
11154
**
11155
** The return value indicates the final state of the session object: 0 if
11156
** the session is disabled, or 1 if it is enabled.
11157
*/
11158
SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
11159
11160
/*
11161
** CAPI3REF: Set Or Clear the Indirect Change Flag
11162
** METHOD: sqlite3_session
11163
**
11164
** Each change recorded by a session object is marked as either direct or
11165
** indirect. A change is marked as indirect if either:
11166
**
11167
** <ul>
11168
**   <li> The session object "indirect" flag is set when the change is
11169
**        made, or
11170
**   <li> The change is made by an SQL trigger or foreign key action
11171
**        instead of directly as a result of a users SQL statement.
11172
** </ul>
11173
**
11174
** If a single row is affected by more than one operation within a session,
11175
** then the change is considered indirect if all operations meet the criteria
11176
** for an indirect change above, or direct otherwise.
11177
**
11178
** This function is used to set, clear or query the session object indirect
11179
** flag.  If the second argument passed to this function is zero, then the
11180
** indirect flag is cleared. If it is greater than zero, the indirect flag
11181
** is set. Passing a value less than zero does not modify the current value
11182
** of the indirect flag, and may be used to query the current state of the
11183
** indirect flag for the specified session object.
11184
**
11185
** The return value indicates the final state of the indirect flag: 0 if
11186
** it is clear, or 1 if it is set.
11187
*/
11188
SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
11189
11190
/*
11191
** CAPI3REF: Attach A Table To A Session Object
11192
** METHOD: sqlite3_session
11193
**
11194
** If argument zTab is not NULL, then it is the name of a table to attach
11195
** to the session object passed as the first argument. All subsequent changes
11196
** made to the table while the session object is enabled will be recorded. See
11197
** documentation for [sqlite3session_changeset()] for further details.
11198
**
11199
** Or, if argument zTab is NULL, then changes are recorded for all tables
11200
** in the database. If additional tables are added to the database (by
11201
** executing "CREATE TABLE" statements) after this call is made, changes for
11202
** the new tables are also recorded.
11203
**
11204
** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
11205
** defined as part of their CREATE TABLE statement. It does not matter if the
11206
** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
11207
** KEY may consist of a single column, or may be a composite key.
11208
**
11209
** It is not an error if the named table does not exist in the database. Nor
11210
** is it an error if the named table does not have a PRIMARY KEY. However,
11211
** no changes will be recorded in either of these scenarios.
11212
**
11213
** Changes are not recorded for individual rows that have NULL values stored
11214
** in one or more of their PRIMARY KEY columns.
11215
**
11216
** SQLITE_OK is returned if the call completes without error. Or, if an error
11217
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
11218
**
11219
** <h3>Special sqlite_stat1 Handling</h3>
11220
**
11221
** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to
11222
** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
11223
**  <pre>
11224
**  &nbsp;     CREATE TABLE sqlite_stat1(tbl,idx,stat)
11225
**  </pre>
11226
**
11227
** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are
11228
** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes
11229
** are recorded for rows for which (idx IS NULL) is true. However, for such
11230
** rows a zero-length blob (SQL value X'') is stored in the changeset or
11231
** patchset instead of a NULL value. This allows such changesets to be
11232
** manipulated by legacy implementations of sqlite3changeset_invert(),
11233
** concat() and similar.
11234
**
11235
** The sqlite3changeset_apply() function automatically converts the
11236
** zero-length blob back to a NULL value when updating the sqlite_stat1
11237
** table. However, if the application calls sqlite3changeset_new(),
11238
** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset
11239
** iterator directly (including on a changeset iterator passed to a
11240
** conflict-handler callback) then the X'' value is returned. The application
11241
** must translate X'' to NULL itself if required.
11242
**
11243
** Legacy (older than 3.22.0) versions of the sessions module cannot capture
11244
** changes made to the sqlite_stat1 table. Legacy versions of the
11245
** sqlite3changeset_apply() function silently ignore any modifications to the
11246
** sqlite_stat1 table that are part of a changeset or patchset.
11247
*/
11248
SQLITE_API int sqlite3session_attach(
11249
  sqlite3_session *pSession,      /* Session object */
11250
  const char *zTab                /* Table name */
11251
);
11252
11253
/*
11254
** CAPI3REF: Set a table filter on a Session Object.
11255
** METHOD: sqlite3_session
11256
**
11257
** The second argument (xFilter) is the "filter callback". For changes to rows
11258
** in tables that are not attached to the Session object, the filter is called
11259
** to determine whether changes to the table's rows should be tracked or not.
11260
** If xFilter returns 0, changes are not tracked. Note that once a table is
11261
** attached, xFilter will not be called again.
11262
*/
11263
SQLITE_API void sqlite3session_table_filter(
11264
  sqlite3_session *pSession,      /* Session object */
11265
  int(*xFilter)(
11266
    void *pCtx,                   /* Copy of third arg to _filter_table() */
11267
    const char *zTab              /* Table name */
11268
  ),
11269
  void *pCtx                      /* First argument passed to xFilter */
11270
);
11271
11272
/*
11273
** CAPI3REF: Generate A Changeset From A Session Object
11274
** METHOD: sqlite3_session
11275
**
11276
** Obtain a changeset containing changes to the tables attached to the
11277
** session object passed as the first argument. If successful,
11278
** set *ppChangeset to point to a buffer containing the changeset
11279
** and *pnChangeset to the size of the changeset in bytes before returning
11280
** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
11281
** zero and return an SQLite error code.
11282
**
11283
** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
11284
** each representing a change to a single row of an attached table. An INSERT
11285
** change contains the values of each field of a new database row. A DELETE
11286
** contains the original values of each field of a deleted database row. An
11287
** UPDATE change contains the original values of each field of an updated
11288
** database row along with the updated values for each updated non-primary-key
11289
** column. It is not possible for an UPDATE change to represent a change that
11290
** modifies the values of primary key columns. If such a change is made, it
11291
** is represented in a changeset as a DELETE followed by an INSERT.
11292
**
11293
** Changes are not recorded for rows that have NULL values stored in one or
11294
** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
11295
** no corresponding change is present in the changesets returned by this
11296
** function. If an existing row with one or more NULL values stored in
11297
** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
11298
** only an INSERT is appears in the changeset. Similarly, if an existing row
11299
** with non-NULL PRIMARY KEY values is updated so that one or more of its
11300
** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
11301
** DELETE change only.
11302
**
11303
** The contents of a changeset may be traversed using an iterator created
11304
** using the [sqlite3changeset_start()] API. A changeset may be applied to
11305
** a database with a compatible schema using the [sqlite3changeset_apply()]
11306
** API.
11307
**
11308
** Within a changeset generated by this function, all changes related to a
11309
** single table are grouped together. In other words, when iterating through
11310
** a changeset or when applying a changeset to a database, all changes related
11311
** to a single table are processed before moving on to the next table. Tables
11312
** are sorted in the same order in which they were attached (or auto-attached)
11313
** to the sqlite3_session object. The order in which the changes related to
11314
** a single table are stored is undefined.
11315
**
11316
** Following a successful call to this function, it is the responsibility of
11317
** the caller to eventually free the buffer that *ppChangeset points to using
11318
** [sqlite3_free()].
11319
**
11320
** <h3>Changeset Generation</h3>
11321
**
11322
** Once a table has been attached to a session object, the session object
11323
** records the primary key values of all new rows inserted into the table.
11324
** It also records the original primary key and other column values of any
11325
** deleted or updated rows. For each unique primary key value, data is only
11326
** recorded once - the first time a row with said primary key is inserted,
11327
** updated or deleted in the lifetime of the session.
11328
**
11329
** There is one exception to the previous paragraph: when a row is inserted,
11330
** updated or deleted, if one or more of its primary key columns contain a
11331
** NULL value, no record of the change is made.
11332
**
11333
** The session object therefore accumulates two types of records - those
11334
** that consist of primary key values only (created when the user inserts
11335
** a new record) and those that consist of the primary key values and the
11336
** original values of other table columns (created when the users deletes
11337
** or updates a record).
11338
**
11339
** When this function is called, the requested changeset is created using
11340
** both the accumulated records and the current contents of the database
11341
** file. Specifically:
11342
**
11343
** <ul>
11344
**   <li> For each record generated by an insert, the database is queried
11345
**        for a row with a matching primary key. If one is found, an INSERT
11346
**        change is added to the changeset. If no such row is found, no change
11347
**        is added to the changeset.
11348
**
11349
**   <li> For each record generated by an update or delete, the database is
11350
**        queried for a row with a matching primary key. If such a row is
11351
**        found and one or more of the non-primary key fields have been
11352
**        modified from their original values, an UPDATE change is added to
11353
**        the changeset. Or, if no such row is found in the table, a DELETE
11354
**        change is added to the changeset. If there is a row with a matching
11355
**        primary key in the database, but all fields contain their original
11356
**        values, no change is added to the changeset.
11357
** </ul>
11358
**
11359
** This means, amongst other things, that if a row is inserted and then later
11360
** deleted while a session object is active, neither the insert nor the delete
11361
** will be present in the changeset. Or if a row is deleted and then later a
11362
** row with the same primary key values inserted while a session object is
11363
** active, the resulting changeset will contain an UPDATE change instead of
11364
** a DELETE and an INSERT.
11365
**
11366
** When a session object is disabled (see the [sqlite3session_enable()] API),
11367
** it does not accumulate records when rows are inserted, updated or deleted.
11368
** This may appear to have some counter-intuitive effects if a single row
11369
** is written to more than once during a session. For example, if a row
11370
** is inserted while a session object is enabled, then later deleted while
11371
** the same session object is disabled, no INSERT record will appear in the
11372
** changeset, even though the delete took place while the session was disabled.
11373
** Or, if one field of a row is updated while a session is disabled, and
11374
** another field of the same row is updated while the session is enabled, the
11375
** resulting changeset will contain an UPDATE change that updates both fields.
11376
*/
11377
SQLITE_API int sqlite3session_changeset(
11378
  sqlite3_session *pSession,      /* Session object */
11379
  int *pnChangeset,               /* OUT: Size of buffer at *ppChangeset */
11380
  void **ppChangeset              /* OUT: Buffer containing changeset */
11381
);
11382
11383
/*
11384
** CAPI3REF: Return An Upper-limit For The Size Of The Changeset
11385
** METHOD: sqlite3_session
11386
**
11387
** By default, this function always returns 0. For it to return
11388
** a useful result, the sqlite3_session object must have been configured
11389
** to enable this API using sqlite3session_object_config() with the
11390
** SQLITE_SESSION_OBJCONFIG_SIZE verb.
11391
**
11392
** When enabled, this function returns an upper limit, in bytes, for the size
11393
** of the changeset that might be produced if sqlite3session_changeset() were
11394
** called. The final changeset size might be equal to or smaller than the
11395
** size in bytes returned by this function.
11396
*/
11397
SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession);
11398
11399
/*
11400
** CAPI3REF: Load The Difference Between Tables Into A Session
11401
** METHOD: sqlite3_session
11402
**
11403
** If it is not already attached to the session object passed as the first
11404
** argument, this function attaches table zTbl in the same manner as the
11405
** [sqlite3session_attach()] function. If zTbl does not exist, or if it
11406
** does not have a primary key, this function is a no-op (but does not return
11407
** an error).
11408
**
11409
** Argument zFromDb must be the name of a database ("main", "temp" etc.)
11410
** attached to the same database handle as the session object that contains
11411
** a table compatible with the table attached to the session by this function.
11412
** A table is considered compatible if it:
11413
**
11414
** <ul>
11415
**   <li> Has the same name,
11416
**   <li> Has the same set of columns declared in the same order, and
11417
**   <li> Has the same PRIMARY KEY definition.
11418
** </ul>
11419
**
11420
** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
11421
** are compatible but do not have any PRIMARY KEY columns, it is not an error
11422
** but no changes are added to the session object. As with other session
11423
** APIs, tables without PRIMARY KEYs are simply ignored.
11424
**
11425
** This function adds a set of changes to the session object that could be
11426
** used to update the table in database zFrom (call this the "from-table")
11427
** so that its content is the same as the table attached to the session
11428
** object (call this the "to-table"). Specifically:
11429
**
11430
** <ul>
11431
**   <li> For each row (primary key) that exists in the to-table but not in
11432
**     the from-table, an INSERT record is added to the session object.
11433
**
11434
**   <li> For each row (primary key) that exists in the to-table but not in
11435
**     the from-table, a DELETE record is added to the session object.
11436
**
11437
**   <li> For each row (primary key) that exists in both tables, but features
11438
**     different non-PK values in each, an UPDATE record is added to the
11439
**     session.
11440
** </ul>
11441
**
11442
** To clarify, if this function is called and then a changeset constructed
11443
** using [sqlite3session_changeset()], then after applying that changeset to
11444
** database zFrom the contents of the two compatible tables would be
11445
** identical.
11446
**
11447
** It an error if database zFrom does not exist or does not contain the
11448
** required compatible table.
11449
**
11450
** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite
11451
** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
11452
** may be set to point to a buffer containing an English language error
11453
** message. It is the responsibility of the caller to free this buffer using
11454
** sqlite3_free().
11455
*/
11456
SQLITE_API int sqlite3session_diff(
11457
  sqlite3_session *pSession,
11458
  const char *zFromDb,
11459
  const char *zTbl,
11460
  char **pzErrMsg
11461
);
11462
11463
11464
/*
11465
** CAPI3REF: Generate A Patchset From A Session Object
11466
** METHOD: sqlite3_session
11467
**
11468
** The differences between a patchset and a changeset are that:
11469
**
11470
** <ul>
11471
**   <li> DELETE records consist of the primary key fields only. The
11472
**        original values of other fields are omitted.
11473
**   <li> The original values of any modified fields are omitted from
11474
**        UPDATE records.
11475
** </ul>
11476
**
11477
** A patchset blob may be used with up to date versions of all
11478
** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
11479
** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
11480
** attempting to use a patchset blob with old versions of the
11481
** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
11482
**
11483
** Because the non-primary key "old.*" fields are omitted, no
11484
** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
11485
** is passed to the sqlite3changeset_apply() API. Other conflict types work
11486
** in the same way as for changesets.
11487
**
11488
** Changes within a patchset are ordered in the same way as for changesets
11489
** generated by the sqlite3session_changeset() function (i.e. all changes for
11490
** a single table are grouped together, tables appear in the order in which
11491
** they were attached to the session object).
11492
*/
11493
SQLITE_API int sqlite3session_patchset(
11494
  sqlite3_session *pSession,      /* Session object */
11495
  int *pnPatchset,                /* OUT: Size of buffer at *ppPatchset */
11496
  void **ppPatchset               /* OUT: Buffer containing patchset */
11497
);
11498
11499
/*
11500
** CAPI3REF: Test if a changeset has recorded any changes.
11501
**
11502
** Return non-zero if no changes to attached tables have been recorded by
11503
** the session object passed as the first argument. Otherwise, if one or
11504
** more changes have been recorded, return zero.
11505
**
11506
** Even if this function returns zero, it is possible that calling
11507
** [sqlite3session_changeset()] on the session handle may still return a
11508
** changeset that contains no changes. This can happen when a row in
11509
** an attached table is modified and then later on the original values
11510
** are restored. However, if this function returns non-zero, then it is
11511
** guaranteed that a call to sqlite3session_changeset() will return a
11512
** changeset containing zero changes.
11513
*/
11514
SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
11515
11516
/*
11517
** CAPI3REF: Query for the amount of heap memory used by a session object.
11518
**
11519
** This API returns the total amount of heap memory in bytes currently
11520
** used by the session object passed as the only argument.
11521
*/
11522
SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession);
11523
11524
/*
11525
** CAPI3REF: Create An Iterator To Traverse A Changeset
11526
** CONSTRUCTOR: sqlite3_changeset_iter
11527
**
11528
** Create an iterator used to iterate through the contents of a changeset.
11529
** If successful, *pp is set to point to the iterator handle and SQLITE_OK
11530
** is returned. Otherwise, if an error occurs, *pp is set to zero and an
11531
** SQLite error code is returned.
11532
**
11533
** The following functions can be used to advance and query a changeset
11534
** iterator created by this function:
11535
**
11536
** <ul>
11537
**   <li> [sqlite3changeset_next()]
11538
**   <li> [sqlite3changeset_op()]
11539
**   <li> [sqlite3changeset_new()]
11540
**   <li> [sqlite3changeset_old()]
11541
** </ul>
11542
**
11543
** It is the responsibility of the caller to eventually destroy the iterator
11544
** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
11545
** changeset (pChangeset) must remain valid until after the iterator is
11546
** destroyed.
11547
**
11548
** Assuming the changeset blob was created by one of the
11549
** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
11550
** [sqlite3changeset_invert()] functions, all changes within the changeset
11551
** that apply to a single table are grouped together. This means that when
11552
** an application iterates through a changeset using an iterator created by
11553
** this function, all changes that relate to a single table are visited
11554
** consecutively. There is no chance that the iterator will visit a change
11555
** the applies to table X, then one for table Y, and then later on visit
11556
** another change for table X.
11557
**
11558
** The behavior of sqlite3changeset_start_v2() and its streaming equivalent
11559
** may be modified by passing a combination of
11560
** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter.
11561
**
11562
** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b>
11563
** and therefore subject to change.
11564
*/
11565
SQLITE_API int sqlite3changeset_start(
11566
  sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
11567
  int nChangeset,                 /* Size of changeset blob in bytes */
11568
  void *pChangeset                /* Pointer to blob containing changeset */
11569
);
11570
SQLITE_API int sqlite3changeset_start_v2(
11571
  sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
11572
  int nChangeset,                 /* Size of changeset blob in bytes */
11573
  void *pChangeset,               /* Pointer to blob containing changeset */
11574
  int flags                       /* SESSION_CHANGESETSTART_* flags */
11575
);
11576
11577
/*
11578
** CAPI3REF: Flags for sqlite3changeset_start_v2
11579
**
11580
** The following flags may passed via the 4th parameter to
11581
** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]:
11582
**
11583
** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
11584
**   Invert the changeset while iterating through it. This is equivalent to
11585
**   inverting a changeset using sqlite3changeset_invert() before applying it.
11586
**   It is an error to specify this flag with a patchset.
11587
*/
11588
#define SQLITE_CHANGESETSTART_INVERT        0x0002
11589
11590
11591
/*
11592
** CAPI3REF: Advance A Changeset Iterator
11593
** METHOD: sqlite3_changeset_iter
11594
**
11595
** This function may only be used with iterators created by the function
11596
** [sqlite3changeset_start()]. If it is called on an iterator passed to
11597
** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
11598
** is returned and the call has no effect.
11599
**
11600
** Immediately after an iterator is created by sqlite3changeset_start(), it
11601
** does not point to any change in the changeset. Assuming the changeset
11602
** is not empty, the first call to this function advances the iterator to
11603
** point to the first change in the changeset. Each subsequent call advances
11604
** the iterator to point to the next change in the changeset (if any). If
11605
** no error occurs and the iterator points to a valid change after a call
11606
** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
11607
** Otherwise, if all changes in the changeset have already been visited,
11608
** SQLITE_DONE is returned.
11609
**
11610
** If an error occurs, an SQLite error code is returned. Possible error
11611
** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
11612
** SQLITE_NOMEM.
11613
*/
11614
SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
11615
11616
/*
11617
** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
11618
** METHOD: sqlite3_changeset_iter
11619
**
11620
** The pIter argument passed to this function may either be an iterator
11621
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11622
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11623
** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
11624
** is not the case, this function returns [SQLITE_MISUSE].
11625
**
11626
** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three
11627
** outputs are set through these pointers:
11628
**
11629
** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
11630
** depending on the type of change that the iterator currently points to;
11631
**
11632
** *pnCol is set to the number of columns in the table affected by the change; and
11633
**
11634
** *pzTab is set to point to a nul-terminated utf-8 encoded string containing
11635
** the name of the table affected by the current change. The buffer remains
11636
** valid until either sqlite3changeset_next() is called on the iterator
11637
** or until the conflict-handler function returns.
11638
**
11639
** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change
11640
** is an indirect change, or false (0) otherwise. See the documentation for
11641
** [sqlite3session_indirect()] for a description of direct and indirect
11642
** changes.
11643
**
11644
** If no error occurs, SQLITE_OK is returned. If an error does occur, an
11645
** SQLite error code is returned. The values of the output variables may not
11646
** be trusted in this case.
11647
*/
11648
SQLITE_API int sqlite3changeset_op(
11649
  sqlite3_changeset_iter *pIter,  /* Iterator object */
11650
  const char **pzTab,             /* OUT: Pointer to table name */
11651
  int *pnCol,                     /* OUT: Number of columns in table */
11652
  int *pOp,                       /* OUT: SQLITE_INSERT, DELETE or UPDATE */
11653
  int *pbIndirect                 /* OUT: True for an 'indirect' change */
11654
);
11655
11656
/*
11657
** CAPI3REF: Obtain The Primary Key Definition Of A Table
11658
** METHOD: sqlite3_changeset_iter
11659
**
11660
** For each modified table, a changeset includes the following:
11661
**
11662
** <ul>
11663
**   <li> The number of columns in the table, and
11664
**   <li> Which of those columns make up the tables PRIMARY KEY.
11665
** </ul>
11666
**
11667
** This function is used to find which columns comprise the PRIMARY KEY of
11668
** the table modified by the change that iterator pIter currently points to.
11669
** If successful, *pabPK is set to point to an array of nCol entries, where
11670
** nCol is the number of columns in the table. Elements of *pabPK are set to
11671
** 0x01 if the corresponding column is part of the tables primary key, or
11672
** 0x00 if it is not.
11673
**
11674
** If argument pnCol is not NULL, then *pnCol is set to the number of columns
11675
** in the table.
11676
**
11677
** If this function is called when the iterator does not point to a valid
11678
** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
11679
** SQLITE_OK is returned and the output variables populated as described
11680
** above.
11681
*/
11682
SQLITE_API int sqlite3changeset_pk(
11683
  sqlite3_changeset_iter *pIter,  /* Iterator object */
11684
  unsigned char **pabPK,          /* OUT: Array of boolean - true for PK cols */
11685
  int *pnCol                      /* OUT: Number of entries in output array */
11686
);
11687
11688
/*
11689
** CAPI3REF: Obtain old.* Values From A Changeset Iterator
11690
** METHOD: sqlite3_changeset_iter
11691
**
11692
** The pIter argument passed to this function may either be an iterator
11693
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11694
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11695
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
11696
** Furthermore, it may only be called if the type of change that the iterator
11697
** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
11698
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
11699
**
11700
** Argument iVal must be greater than or equal to 0, and less than the number
11701
** of columns in the table affected by the current change. Otherwise,
11702
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11703
**
11704
** If successful, this function sets *ppValue to point to a protected
11705
** sqlite3_value object containing the iVal'th value from the vector of
11706
** original row values stored as part of the UPDATE or DELETE change and
11707
** returns SQLITE_OK. The name of the function comes from the fact that this
11708
** is similar to the "old.*" columns available to update or delete triggers.
11709
**
11710
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11711
** is returned and *ppValue is set to NULL.
11712
*/
11713
SQLITE_API int sqlite3changeset_old(
11714
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11715
  int iVal,                       /* Column number */
11716
  sqlite3_value **ppValue         /* OUT: Old value (or NULL pointer) */
11717
);
11718
11719
/*
11720
** CAPI3REF: Obtain new.* Values From A Changeset Iterator
11721
** METHOD: sqlite3_changeset_iter
11722
**
11723
** The pIter argument passed to this function may either be an iterator
11724
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
11725
** created by [sqlite3changeset_start()]. In the latter case, the most recent
11726
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
11727
** Furthermore, it may only be called if the type of change that the iterator
11728
** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
11729
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
11730
**
11731
** Argument iVal must be greater than or equal to 0, and less than the number
11732
** of columns in the table affected by the current change. Otherwise,
11733
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11734
**
11735
** If successful, this function sets *ppValue to point to a protected
11736
** sqlite3_value object containing the iVal'th value from the vector of
11737
** new row values stored as part of the UPDATE or INSERT change and
11738
** returns SQLITE_OK. If the change is an UPDATE and does not include
11739
** a new value for the requested column, *ppValue is set to NULL and
11740
** SQLITE_OK returned. The name of the function comes from the fact that
11741
** this is similar to the "new.*" columns available to update or delete
11742
** triggers.
11743
**
11744
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11745
** is returned and *ppValue is set to NULL.
11746
*/
11747
SQLITE_API int sqlite3changeset_new(
11748
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11749
  int iVal,                       /* Column number */
11750
  sqlite3_value **ppValue         /* OUT: New value (or NULL pointer) */
11751
);
11752
11753
/*
11754
** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
11755
** METHOD: sqlite3_changeset_iter
11756
**
11757
** This function should only be used with iterator objects passed to a
11758
** conflict-handler callback by [sqlite3changeset_apply()] with either
11759
** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
11760
** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
11761
** is set to NULL.
11762
**
11763
** Argument iVal must be greater than or equal to 0, and less than the number
11764
** of columns in the table affected by the current change. Otherwise,
11765
** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
11766
**
11767
** If successful, this function sets *ppValue to point to a protected
11768
** sqlite3_value object containing the iVal'th value from the
11769
** "conflicting row" associated with the current conflict-handler callback
11770
** and returns SQLITE_OK.
11771
**
11772
** If some other error occurs (e.g. an OOM condition), an SQLite error code
11773
** is returned and *ppValue is set to NULL.
11774
*/
11775
SQLITE_API int sqlite3changeset_conflict(
11776
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11777
  int iVal,                       /* Column number */
11778
  sqlite3_value **ppValue         /* OUT: Value from conflicting row */
11779
);
11780
11781
/*
11782
** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
11783
** METHOD: sqlite3_changeset_iter
11784
**
11785
** This function may only be called with an iterator passed to an
11786
** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
11787
** it sets the output variable to the total number of known foreign key
11788
** violations in the destination database and returns SQLITE_OK.
11789
**
11790
** In all other cases this function returns SQLITE_MISUSE.
11791
*/
11792
SQLITE_API int sqlite3changeset_fk_conflicts(
11793
  sqlite3_changeset_iter *pIter,  /* Changeset iterator */
11794
  int *pnOut                      /* OUT: Number of FK violations */
11795
);
11796
11797
11798
/*
11799
** CAPI3REF: Finalize A Changeset Iterator
11800
** METHOD: sqlite3_changeset_iter
11801
**
11802
** This function is used to finalize an iterator allocated with
11803
** [sqlite3changeset_start()].
11804
**
11805
** This function should only be called on iterators created using the
11806
** [sqlite3changeset_start()] function. If an application calls this
11807
** function with an iterator passed to a conflict-handler by
11808
** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
11809
** call has no effect.
11810
**
11811
** If an error was encountered within a call to an sqlite3changeset_xxx()
11812
** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
11813
** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
11814
** to that error is returned by this function. Otherwise, SQLITE_OK is
11815
** returned. This is to allow the following pattern (pseudo-code):
11816
**
11817
** <pre>
11818
**   sqlite3changeset_start();
11819
**   while( SQLITE_ROW==sqlite3changeset_next() ){
11820
**     // Do something with change.
11821
**   }
11822
**   rc = sqlite3changeset_finalize();
11823
**   if( rc!=SQLITE_OK ){
11824
**     // An error has occurred
11825
**   }
11826
** </pre>
11827
*/
11828
SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
11829
11830
/*
11831
** CAPI3REF: Invert A Changeset
11832
**
11833
** This function is used to "invert" a changeset object. Applying an inverted
11834
** changeset to a database reverses the effects of applying the uninverted
11835
** changeset. Specifically:
11836
**
11837
** <ul>
11838
**   <li> Each DELETE change is changed to an INSERT, and
11839
**   <li> Each INSERT change is changed to a DELETE, and
11840
**   <li> For each UPDATE change, the old.* and new.* values are exchanged.
11841
** </ul>
11842
**
11843
** This function does not change the order in which changes appear within
11844
** the changeset. It merely reverses the sense of each individual change.
11845
**
11846
** If successful, a pointer to a buffer containing the inverted changeset
11847
** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
11848
** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
11849
** zeroed and an SQLite error code returned.
11850
**
11851
** It is the responsibility of the caller to eventually call sqlite3_free()
11852
** on the *ppOut pointer to free the buffer allocation following a successful
11853
** call to this function.
11854
**
11855
** WARNING/TODO: This function currently assumes that the input is a valid
11856
** changeset. If it is not, the results are undefined.
11857
*/
11858
SQLITE_API int sqlite3changeset_invert(
11859
  int nIn, const void *pIn,       /* Input changeset */
11860
  int *pnOut, void **ppOut        /* OUT: Inverse of input */
11861
);
11862
11863
/*
11864
** CAPI3REF: Concatenate Two Changeset Objects
11865
**
11866
** This function is used to concatenate two changesets, A and B, into a
11867
** single changeset. The result is a changeset equivalent to applying
11868
** changeset A followed by changeset B.
11869
**
11870
** This function combines the two input changesets using an
11871
** sqlite3_changegroup object. Calling it produces similar results as the
11872
** following code fragment:
11873
**
11874
** <pre>
11875
**   sqlite3_changegroup *pGrp;
11876
**   rc = sqlite3_changegroup_new(&pGrp);
11877
**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
11878
**   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
11879
**   if( rc==SQLITE_OK ){
11880
**     rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
11881
**   }else{
11882
**     *ppOut = 0;
11883
**     *pnOut = 0;
11884
**   }
11885
** </pre>
11886
**
11887
** Refer to the sqlite3_changegroup documentation below for details.
11888
*/
11889
SQLITE_API int sqlite3changeset_concat(
11890
  int nA,                         /* Number of bytes in buffer pA */
11891
  void *pA,                       /* Pointer to buffer containing changeset A */
11892
  int nB,                         /* Number of bytes in buffer pB */
11893
  void *pB,                       /* Pointer to buffer containing changeset B */
11894
  int *pnOut,                     /* OUT: Number of bytes in output changeset */
11895
  void **ppOut                    /* OUT: Buffer containing output changeset */
11896
);
11897
11898
11899
/*
11900
** CAPI3REF: Upgrade the Schema of a Changeset/Patchset
11901
*/
11902
SQLITE_API int sqlite3changeset_upgrade(
11903
  sqlite3 *db,
11904
  const char *zDb,
11905
  int nIn, const void *pIn,       /* Input changeset */
11906
  int *pnOut, void **ppOut        /* OUT: Inverse of input */
11907
);
11908
11909
11910
11911
/*
11912
** CAPI3REF: Changegroup Handle
11913
**
11914
** A changegroup is an object used to combine two or more
11915
** [changesets] or [patchsets]
11916
*/
11917
typedef struct sqlite3_changegroup sqlite3_changegroup;
11918
11919
/*
11920
** CAPI3REF: Create A New Changegroup Object
11921
** CONSTRUCTOR: sqlite3_changegroup
11922
**
11923
** An sqlite3_changegroup object is used to combine two or more changesets
11924
** (or patchsets) into a single changeset (or patchset). A single changegroup
11925
** object may combine changesets or patchsets, but not both. The output is
11926
** always in the same format as the input.
11927
**
11928
** If successful, this function returns SQLITE_OK and populates (*pp) with
11929
** a pointer to a new sqlite3_changegroup object before returning. The caller
11930
** should eventually free the returned object using a call to
11931
** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
11932
** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
11933
**
11934
** The usual usage pattern for an sqlite3_changegroup object is as follows:
11935
**
11936
** <ul>
11937
**   <li> It is created using a call to sqlite3changegroup_new().
11938
**
11939
**   <li> Zero or more changesets (or patchsets) are added to the object
11940
**        by calling sqlite3changegroup_add().
11941
**
11942
**   <li> The result of combining all input changesets together is obtained
11943
**        by the application via a call to sqlite3changegroup_output().
11944
**
11945
**   <li> The object is deleted using a call to sqlite3changegroup_delete().
11946
** </ul>
11947
**
11948
** Any number of calls to add() and output() may be made between the calls to
11949
** new() and delete(), and in any order.
11950
**
11951
** As well as the regular sqlite3changegroup_add() and
11952
** sqlite3changegroup_output() functions, also available are the streaming
11953
** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
11954
*/
11955
SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
11956
11957
/*
11958
** CAPI3REF: Add a Schema to a Changegroup
11959
** METHOD: sqlite3_changegroup_schema
11960
**
11961
** This method may be used to optionally enforce the rule that the changesets
11962
** added to the changegroup handle must match the schema of database zDb
11963
** ("main", "temp", or the name of an attached database). If
11964
** sqlite3changegroup_add() is called to add a changeset that is not compatible
11965
** with the configured schema, SQLITE_SCHEMA is returned and the changegroup
11966
** object is left in an undefined state.
11967
**
11968
** A changeset schema is considered compatible with the database schema in
11969
** the same way as for sqlite3changeset_apply(). Specifically, for each
11970
** table in the changeset, there exists a database table with:
11971
**
11972
** <ul>
11973
**   <li> The name identified by the changeset, and
11974
**   <li> at least as many columns as recorded in the changeset, and
11975
**   <li> the primary key columns in the same position as recorded in
11976
**        the changeset.
11977
** </ul>
11978
**
11979
** The output of the changegroup object always has the same schema as the
11980
** database nominated using this function. In cases where changesets passed
11981
** to sqlite3changegroup_add() have fewer columns than the corresponding table
11982
** in the database schema, these are filled in using the default column
11983
** values from the database schema. This makes it possible to combined
11984
** changesets that have different numbers of columns for a single table
11985
** within a changegroup, provided that they are otherwise compatible.
11986
*/
11987
SQLITE_API int sqlite3changegroup_schema(sqlite3_changegroup*, sqlite3*, const char *zDb);
11988
11989
/*
11990
** CAPI3REF: Add A Changeset To A Changegroup
11991
** METHOD: sqlite3_changegroup
11992
**
11993
** Add all changes within the changeset (or patchset) in buffer pData (size
11994
** nData bytes) to the changegroup.
11995
**
11996
** If the buffer contains a patchset, then all prior calls to this function
11997
** on the same changegroup object must also have specified patchsets. Or, if
11998
** the buffer contains a changeset, so must have the earlier calls to this
11999
** function. Otherwise, SQLITE_ERROR is returned and no changes are added
12000
** to the changegroup.
12001
**
12002
** Rows within the changeset and changegroup are identified by the values in
12003
** their PRIMARY KEY columns. A change in the changeset is considered to
12004
** apply to the same row as a change already present in the changegroup if
12005
** the two rows have the same primary key.
12006
**
12007
** Changes to rows that do not already appear in the changegroup are
12008
** simply copied into it. Or, if both the new changeset and the changegroup
12009
** contain changes that apply to a single row, the final contents of the
12010
** changegroup depends on the type of each change, as follows:
12011
**
12012
** <table border=1 style="margin-left:8ex;margin-right:8ex">
12013
**   <tr><th style="white-space:pre">Existing Change  </th>
12014
**       <th style="white-space:pre">New Change       </th>
12015
**       <th>Output Change
12016
**   <tr><td>INSERT <td>INSERT <td>
12017
**       The new change is ignored. This case does not occur if the new
12018
**       changeset was recorded immediately after the changesets already
12019
**       added to the changegroup.
12020
**   <tr><td>INSERT <td>UPDATE <td>
12021
**       The INSERT change remains in the changegroup. The values in the
12022
**       INSERT change are modified as if the row was inserted by the
12023
**       existing change and then updated according to the new change.
12024
**   <tr><td>INSERT <td>DELETE <td>
12025
**       The existing INSERT is removed from the changegroup. The DELETE is
12026
**       not added.
12027
**   <tr><td>UPDATE <td>INSERT <td>
12028
**       The new change is ignored. This case does not occur if the new
12029
**       changeset was recorded immediately after the changesets already
12030
**       added to the changegroup.
12031
**   <tr><td>UPDATE <td>UPDATE <td>
12032
**       The existing UPDATE remains within the changegroup. It is amended
12033
**       so that the accompanying values are as if the row was updated once
12034
**       by the existing change and then again by the new change.
12035
**   <tr><td>UPDATE <td>DELETE <td>
12036
**       The existing UPDATE is replaced by the new DELETE within the
12037
**       changegroup.
12038
**   <tr><td>DELETE <td>INSERT <td>
12039
**       If one or more of the column values in the row inserted by the
12040
**       new change differ from those in the row deleted by the existing
12041
**       change, the existing DELETE is replaced by an UPDATE within the
12042
**       changegroup. Otherwise, if the inserted row is exactly the same
12043
**       as the deleted row, the existing DELETE is simply discarded.
12044
**   <tr><td>DELETE <td>UPDATE <td>
12045
**       The new change is ignored. This case does not occur if the new
12046
**       changeset was recorded immediately after the changesets already
12047
**       added to the changegroup.
12048
**   <tr><td>DELETE <td>DELETE <td>
12049
**       The new change is ignored. This case does not occur if the new
12050
**       changeset was recorded immediately after the changesets already
12051
**       added to the changegroup.
12052
** </table>
12053
**
12054
** If the new changeset contains changes to a table that is already present
12055
** in the changegroup, then the number of columns and the position of the
12056
** primary key columns for the table must be consistent. If this is not the
12057
** case, this function fails with SQLITE_SCHEMA. Except, if the changegroup
12058
** object has been configured with a database schema using the
12059
** sqlite3changegroup_schema() API, then it is possible to combine changesets
12060
** with different numbers of columns for a single table, provided that
12061
** they are otherwise compatible.
12062
**
12063
** If the input changeset appears to be corrupt and the corruption is
12064
** detected, SQLITE_CORRUPT is returned. Or, if an out-of-memory condition
12065
** occurs during processing, this function returns SQLITE_NOMEM.
12066
**
12067
** In all cases, if an error occurs the state of the final contents of the
12068
** changegroup is undefined. If no error occurs, SQLITE_OK is returned.
12069
*/
12070
SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
12071
12072
/*
12073
** CAPI3REF: Add A Single Change To A Changegroup
12074
** METHOD: sqlite3_changegroup
12075
**
12076
** This function adds the single change currently indicated by the iterator
12077
** passed as the second argument to the changegroup object. The rules for
12078
** adding the change are just as described for [sqlite3changegroup_add()].
12079
**
12080
** If the change is successfully added to the changegroup, SQLITE_OK is
12081
** returned. Otherwise, an SQLite error code is returned.
12082
**
12083
** The iterator must point to a valid entry when this function is called.
12084
** If it does not, SQLITE_ERROR is returned and no change is added to the
12085
** changegroup. Additionally, the iterator must not have been opened with
12086
** the SQLITE_CHANGESETAPPLY_INVERT flag. In this case SQLITE_ERROR is also
12087
** returned.
12088
*/
12089
SQLITE_API int sqlite3changegroup_add_change(
12090
  sqlite3_changegroup*,
12091
  sqlite3_changeset_iter*
12092
);
12093
12094
12095
12096
/*
12097
** CAPI3REF: Obtain A Composite Changeset From A Changegroup
12098
** METHOD: sqlite3_changegroup
12099
**
12100
** Obtain a buffer containing a changeset (or patchset) representing the
12101
** current contents of the changegroup. If the inputs to the changegroup
12102
** were themselves changesets, the output is a changeset. Or, if the
12103
** inputs were patchsets, the output is also a patchset.
12104
**
12105
** As with the output of the sqlite3session_changeset() and
12106
** sqlite3session_patchset() functions, all changes related to a single
12107
** table are grouped together in the output of this function. Tables appear
12108
** in the same order as for the very first changeset added to the changegroup.
12109
** If the second or subsequent changesets added to the changegroup contain
12110
** changes for tables that do not appear in the first changeset, they are
12111
** appended onto the end of the output changeset, again in the order in
12112
** which they are first encountered.
12113
**
12114
** If an error occurs, an SQLite error code is returned and the output
12115
** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
12116
** is returned and the output variables are set to the size of and a
12117
** pointer to the output buffer, respectively. In this case it is the
12118
** responsibility of the caller to eventually free the buffer using a
12119
** call to sqlite3_free().
12120
*/
12121
SQLITE_API int sqlite3changegroup_output(
12122
  sqlite3_changegroup*,
12123
  int *pnData,                    /* OUT: Size of output buffer in bytes */
12124
  void **ppData                   /* OUT: Pointer to output buffer */
12125
);
12126
12127
/*
12128
** CAPI3REF: Delete A Changegroup Object
12129
** DESTRUCTOR: sqlite3_changegroup
12130
*/
12131
SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
12132
12133
/*
12134
** CAPI3REF: Apply A Changeset To A Database
12135
**
12136
** Apply a changeset or patchset to a database. These functions attempt to
12137
** update the "main" database attached to handle db with the changes found in
12138
** the changeset passed via the second and third arguments.
12139
**
12140
** The fourth argument (xFilter) passed to these functions is the "filter
12141
** callback". If it is not NULL, then for each table affected by at least one
12142
** change in the changeset, the filter callback is invoked with
12143
** the table name as the second argument, and a copy of the context pointer
12144
** passed as the sixth argument as the first. If the "filter callback"
12145
** returns zero, then no attempt is made to apply any changes to the table.
12146
** Otherwise, if the return value is non-zero or the xFilter argument to
12147
** is NULL, all changes related to the table are attempted.
12148
**
12149
** For each table that is not excluded by the filter callback, this function
12150
** tests that the target database contains a compatible table. A table is
12151
** considered compatible if all of the following are true:
12152
**
12153
** <ul>
12154
**   <li> The table has the same name as the name recorded in the
12155
**        changeset, and
12156
**   <li> The table has at least as many columns as recorded in the
12157
**        changeset, and
12158
**   <li> The table has primary key columns in the same position as
12159
**        recorded in the changeset.
12160
** </ul>
12161
**
12162
** If there is no compatible table, it is not an error, but none of the
12163
** changes associated with the table are applied. A warning message is issued
12164
** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
12165
** one such warning is issued for each table in the changeset.
12166
**
12167
** For each change for which there is a compatible table, an attempt is made
12168
** to modify the table contents according to the UPDATE, INSERT or DELETE
12169
** change. If a change cannot be applied cleanly, the conflict handler
12170
** function passed as the fifth argument to sqlite3changeset_apply() may be
12171
** invoked. A description of exactly when the conflict handler is invoked for
12172
** each type of change is below.
12173
**
12174
** Unlike the xFilter argument, xConflict may not be passed NULL. The results
12175
** of passing anything other than a valid function pointer as the xConflict
12176
** argument are undefined.
12177
**
12178
** Each time the conflict handler function is invoked, it must return one
12179
** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
12180
** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
12181
** if the second argument passed to the conflict handler is either
12182
** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
12183
** returns an illegal value, any changes already made are rolled back and
12184
** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
12185
** actions are taken by sqlite3changeset_apply() depending on the value
12186
** returned by each invocation of the conflict-handler function. Refer to
12187
** the documentation for the three
12188
** [SQLITE_CHANGESET_OMIT|available return values] for details.
12189
**
12190
** <dl>
12191
** <dt>DELETE Changes<dd>
12192
**   For each DELETE change, the function checks if the target database
12193
**   contains a row with the same primary key value (or values) as the
12194
**   original row values stored in the changeset. If it does, and the values
12195
**   stored in all non-primary key columns also match the values stored in
12196
**   the changeset the row is deleted from the target database.
12197
**
12198
**   If a row with matching primary key values is found, but one or more of
12199
**   the non-primary key fields contains a value different from the original
12200
**   row value stored in the changeset, the conflict-handler function is
12201
**   invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
12202
**   database table has more columns than are recorded in the changeset,
12203
**   only the values of those non-primary key fields are compared against
12204
**   the current database contents - any trailing database table columns
12205
**   are ignored.
12206
**
12207
**   If no row with matching primary key values is found in the database,
12208
**   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
12209
**   passed as the second argument.
12210
**
12211
**   If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
12212
**   (which can only happen if a foreign key constraint is violated), the
12213
**   conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
12214
**   passed as the second argument. This includes the case where the DELETE
12215
**   operation is attempted because an earlier call to the conflict handler
12216
**   function returned [SQLITE_CHANGESET_REPLACE].
12217
**
12218
** <dt>INSERT Changes<dd>
12219
**   For each INSERT change, an attempt is made to insert the new row into
12220
**   the database. If the changeset row contains fewer fields than the
12221
**   database table, the trailing fields are populated with their default
12222
**   values.
12223
**
12224
**   If the attempt to insert the row fails because the database already
12225
**   contains a row with the same primary key values, the conflict handler
12226
**   function is invoked with the second argument set to
12227
**   [SQLITE_CHANGESET_CONFLICT].
12228
**
12229
**   If the attempt to insert the row fails because of some other constraint
12230
**   violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
12231
**   invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
12232
**   This includes the case where the INSERT operation is re-attempted because
12233
**   an earlier call to the conflict handler function returned
12234
**   [SQLITE_CHANGESET_REPLACE].
12235
**
12236
** <dt>UPDATE Changes<dd>
12237
**   For each UPDATE change, the function checks if the target database
12238
**   contains a row with the same primary key value (or values) as the
12239
**   original row values stored in the changeset. If it does, and the values
12240
**   stored in all modified non-primary key columns also match the values
12241
**   stored in the changeset the row is updated within the target database.
12242
**
12243
**   If a row with matching primary key values is found, but one or more of
12244
**   the modified non-primary key fields contains a value different from an
12245
**   original row value stored in the changeset, the conflict-handler function
12246
**   is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
12247
**   UPDATE changes only contain values for non-primary key fields that are
12248
**   to be modified, only those fields need to match the original values to
12249
**   avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
12250
**
12251
**   If no row with matching primary key values is found in the database,
12252
**   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
12253
**   passed as the second argument.
12254
**
12255
**   If the UPDATE operation is attempted, but SQLite returns
12256
**   SQLITE_CONSTRAINT, the conflict-handler function is invoked with
12257
**   [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
12258
**   This includes the case where the UPDATE operation is attempted after
12259
**   an earlier call to the conflict handler function returned
12260
**   [SQLITE_CHANGESET_REPLACE].
12261
** </dl>
12262
**
12263
** It is safe to execute SQL statements, including those that write to the
12264
** table that the callback related to, from within the xConflict callback.
12265
** This can be used to further customize the application's conflict
12266
** resolution strategy.
12267
**
12268
** All changes made by these functions are enclosed in a savepoint transaction.
12269
** If any other error (aside from a constraint failure when attempting to
12270
** write to the target database) occurs, then the savepoint transaction is
12271
** rolled back, restoring the target database to its original state, and an
12272
** SQLite error code returned.
12273
**
12274
** If the output parameters (ppRebase) and (pnRebase) are non-NULL and
12275
** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2()
12276
** may set (*ppRebase) to point to a "rebase" that may be used with the
12277
** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase)
12278
** is set to the size of the buffer in bytes. It is the responsibility of the
12279
** caller to eventually free any such buffer using sqlite3_free(). The buffer
12280
** is only allocated and populated if one or more conflicts were encountered
12281
** while applying the patchset. See comments surrounding the sqlite3_rebaser
12282
** APIs for further details.
12283
**
12284
** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent
12285
** may be modified by passing a combination of
12286
** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter.
12287
**
12288
** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b>
12289
** and therefore subject to change.
12290
*/
12291
SQLITE_API int sqlite3changeset_apply(
12292
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12293
  int nChangeset,                 /* Size of changeset in bytes */
12294
  void *pChangeset,               /* Changeset blob */
12295
  int(*xFilter)(
12296
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12297
    const char *zTab              /* Table name */
12298
  ),
12299
  int(*xConflict)(
12300
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12301
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12302
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12303
  ),
12304
  void *pCtx                      /* First argument passed to xConflict */
12305
);
12306
SQLITE_API int sqlite3changeset_apply_v2(
12307
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12308
  int nChangeset,                 /* Size of changeset in bytes */
12309
  void *pChangeset,               /* Changeset blob */
12310
  int(*xFilter)(
12311
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12312
    const char *zTab              /* Table name */
12313
  ),
12314
  int(*xConflict)(
12315
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12316
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12317
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12318
  ),
12319
  void *pCtx,                     /* First argument passed to xConflict */
12320
  void **ppRebase, int *pnRebase, /* OUT: Rebase data */
12321
  int flags                       /* SESSION_CHANGESETAPPLY_* flags */
12322
);
12323
12324
/*
12325
** CAPI3REF: Flags for sqlite3changeset_apply_v2
12326
**
12327
** The following flags may passed via the 9th parameter to
12328
** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]:
12329
**
12330
** <dl>
12331
** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd>
12332
**   Usually, the sessions module encloses all operations performed by
12333
**   a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The
12334
**   SAVEPOINT is committed if the changeset or patchset is successfully
12335
**   applied, or rolled back if an error occurs. Specifying this flag
12336
**   causes the sessions module to omit this savepoint. In this case, if the
12337
**   caller has an open transaction or savepoint when apply_v2() is called,
12338
**   it may revert the partially applied changeset by rolling it back.
12339
**
12340
** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
12341
**   Invert the changeset before applying it. This is equivalent to inverting
12342
**   a changeset using sqlite3changeset_invert() before applying it. It is
12343
**   an error to specify this flag with a patchset.
12344
**
12345
** <dt>SQLITE_CHANGESETAPPLY_IGNORENOOP <dd>
12346
**   Do not invoke the conflict handler callback for any changes that
12347
**   would not actually modify the database even if they were applied.
12348
**   Specifically, this means that the conflict handler is not invoked
12349
**   for:
12350
**    <ul>
12351
**    <li>a delete change if the row being deleted cannot be found,
12352
**    <li>an update change if the modified fields are already set to
12353
**        their new values in the conflicting row, or
12354
**    <li>an insert change if all fields of the conflicting row match
12355
**        the row being inserted.
12356
**    </ul>
12357
**
12358
** <dt>SQLITE_CHANGESETAPPLY_FKNOACTION <dd>
12359
**   If this flag it set, then all foreign key constraints in the target
12360
**   database behave as if they were declared with "ON UPDATE NO ACTION ON
12361
**   DELETE NO ACTION", even if they are actually CASCADE, RESTRICT, SET NULL
12362
**   or SET DEFAULT.
12363
*/
12364
#define SQLITE_CHANGESETAPPLY_NOSAVEPOINT   0x0001
12365
#define SQLITE_CHANGESETAPPLY_INVERT        0x0002
12366
#define SQLITE_CHANGESETAPPLY_IGNORENOOP    0x0004
12367
#define SQLITE_CHANGESETAPPLY_FKNOACTION    0x0008
12368
12369
/*
12370
** CAPI3REF: Constants Passed To The Conflict Handler
12371
**
12372
** Values that may be passed as the second argument to a conflict-handler.
12373
**
12374
** <dl>
12375
** <dt>SQLITE_CHANGESET_DATA<dd>
12376
**   The conflict handler is invoked with CHANGESET_DATA as the second argument
12377
**   when processing a DELETE or UPDATE change if a row with the required
12378
**   PRIMARY KEY fields is present in the database, but one or more other
12379
**   (non primary-key) fields modified by the update do not contain the
12380
**   expected "before" values.
12381
**
12382
**   The conflicting row, in this case, is the database row with the matching
12383
**   primary key.
12384
**
12385
** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
12386
**   The conflict handler is invoked with CHANGESET_NOTFOUND as the second
12387
**   argument when processing a DELETE or UPDATE change if a row with the
12388
**   required PRIMARY KEY fields is not present in the database.
12389
**
12390
**   There is no conflicting row in this case. The results of invoking the
12391
**   sqlite3changeset_conflict() API are undefined.
12392
**
12393
** <dt>SQLITE_CHANGESET_CONFLICT<dd>
12394
**   CHANGESET_CONFLICT is passed as the second argument to the conflict
12395
**   handler while processing an INSERT change if the operation would result
12396
**   in duplicate primary key values.
12397
**
12398
**   The conflicting row in this case is the database row with the matching
12399
**   primary key.
12400
**
12401
** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
12402
**   If foreign key handling is enabled, and applying a changeset leaves the
12403
**   database in a state containing foreign key violations, the conflict
12404
**   handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
12405
**   exactly once before the changeset is committed. If the conflict handler
12406
**   returns CHANGESET_OMIT, the changes, including those that caused the
12407
**   foreign key constraint violation, are committed. Or, if it returns
12408
**   CHANGESET_ABORT, the changeset is rolled back.
12409
**
12410
**   No current or conflicting row information is provided. The only function
12411
**   it is possible to call on the supplied sqlite3_changeset_iter handle
12412
**   is sqlite3changeset_fk_conflicts().
12413
**
12414
** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
12415
**   If any other constraint violation occurs while applying a change (i.e.
12416
**   a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
12417
**   invoked with CHANGESET_CONSTRAINT as the second argument.
12418
**
12419
**   There is no conflicting row in this case. The results of invoking the
12420
**   sqlite3changeset_conflict() API are undefined.
12421
**
12422
** </dl>
12423
*/
12424
#define SQLITE_CHANGESET_DATA        1
12425
#define SQLITE_CHANGESET_NOTFOUND    2
12426
#define SQLITE_CHANGESET_CONFLICT    3
12427
#define SQLITE_CHANGESET_CONSTRAINT  4
12428
#define SQLITE_CHANGESET_FOREIGN_KEY 5
12429
12430
/*
12431
** CAPI3REF: Constants Returned By The Conflict Handler
12432
**
12433
** A conflict handler callback must return one of the following three values.
12434
**
12435
** <dl>
12436
** <dt>SQLITE_CHANGESET_OMIT<dd>
12437
**   If a conflict handler returns this value no special action is taken. The
12438
**   change that caused the conflict is not applied. The session module
12439
**   continues to the next change in the changeset.
12440
**
12441
** <dt>SQLITE_CHANGESET_REPLACE<dd>
12442
**   This value may only be returned if the second argument to the conflict
12443
**   handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
12444
**   is not the case, any changes applied so far are rolled back and the
12445
**   call to sqlite3changeset_apply() returns SQLITE_MISUSE.
12446
**
12447
**   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
12448
**   handler, then the conflicting row is either updated or deleted, depending
12449
**   on the type of change.
12450
**
12451
**   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
12452
**   handler, then the conflicting row is removed from the database and a
12453
**   second attempt to apply the change is made. If this second attempt fails,
12454
**   the original row is restored to the database before continuing.
12455
**
12456
** <dt>SQLITE_CHANGESET_ABORT<dd>
12457
**   If this value is returned, any changes applied so far are rolled back
12458
**   and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
12459
** </dl>
12460
*/
12461
#define SQLITE_CHANGESET_OMIT       0
12462
#define SQLITE_CHANGESET_REPLACE    1
12463
#define SQLITE_CHANGESET_ABORT      2
12464
12465
/*
12466
** CAPI3REF: Rebasing changesets
12467
** EXPERIMENTAL
12468
**
12469
** Suppose there is a site hosting a database in state S0. And that
12470
** modifications are made that move that database to state S1 and a
12471
** changeset recorded (the "local" changeset). Then, a changeset based
12472
** on S0 is received from another site (the "remote" changeset) and
12473
** applied to the database. The database is then in state
12474
** (S1+"remote"), where the exact state depends on any conflict
12475
** resolution decisions (OMIT or REPLACE) made while applying "remote".
12476
** Rebasing a changeset is to update it to take those conflict
12477
** resolution decisions into account, so that the same conflicts
12478
** do not have to be resolved elsewhere in the network.
12479
**
12480
** For example, if both the local and remote changesets contain an
12481
** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)":
12482
**
12483
**   local:  INSERT INTO t1 VALUES(1, 'v1');
12484
**   remote: INSERT INTO t1 VALUES(1, 'v2');
12485
**
12486
** and the conflict resolution is REPLACE, then the INSERT change is
12487
** removed from the local changeset (it was overridden). Or, if the
12488
** conflict resolution was "OMIT", then the local changeset is modified
12489
** to instead contain:
12490
**
12491
**           UPDATE t1 SET b = 'v2' WHERE a=1;
12492
**
12493
** Changes within the local changeset are rebased as follows:
12494
**
12495
** <dl>
12496
** <dt>Local INSERT<dd>
12497
**   This may only conflict with a remote INSERT. If the conflict
12498
**   resolution was OMIT, then add an UPDATE change to the rebased
12499
**   changeset. Or, if the conflict resolution was REPLACE, add
12500
**   nothing to the rebased changeset.
12501
**
12502
** <dt>Local DELETE<dd>
12503
**   This may conflict with a remote UPDATE or DELETE. In both cases the
12504
**   only possible resolution is OMIT. If the remote operation was a
12505
**   DELETE, then add no change to the rebased changeset. If the remote
12506
**   operation was an UPDATE, then the old.* fields of change are updated
12507
**   to reflect the new.* values in the UPDATE.
12508
**
12509
** <dt>Local UPDATE<dd>
12510
**   This may conflict with a remote UPDATE or DELETE. If it conflicts
12511
**   with a DELETE, and the conflict resolution was OMIT, then the update
12512
**   is changed into an INSERT. Any undefined values in the new.* record
12513
**   from the update change are filled in using the old.* values from
12514
**   the conflicting DELETE. Or, if the conflict resolution was REPLACE,
12515
**   the UPDATE change is simply omitted from the rebased changeset.
12516
**
12517
**   If conflict is with a remote UPDATE and the resolution is OMIT, then
12518
**   the old.* values are rebased using the new.* values in the remote
12519
**   change. Or, if the resolution is REPLACE, then the change is copied
12520
**   into the rebased changeset with updates to columns also updated by
12521
**   the conflicting remote UPDATE removed. If this means no columns would
12522
**   be updated, the change is omitted.
12523
** </dl>
12524
**
12525
** A local change may be rebased against multiple remote changes
12526
** simultaneously. If a single key is modified by multiple remote
12527
** changesets, they are combined as follows before the local changeset
12528
** is rebased:
12529
**
12530
** <ul>
12531
**    <li> If there has been one or more REPLACE resolutions on a
12532
**         key, it is rebased according to a REPLACE.
12533
**
12534
**    <li> If there have been no REPLACE resolutions on a key, then
12535
**         the local changeset is rebased according to the most recent
12536
**         of the OMIT resolutions.
12537
** </ul>
12538
**
12539
** Note that conflict resolutions from multiple remote changesets are
12540
** combined on a per-field basis, not per-row. This means that in the
12541
** case of multiple remote UPDATE operations, some fields of a single
12542
** local change may be rebased for REPLACE while others are rebased for
12543
** OMIT.
12544
**
12545
** In order to rebase a local changeset, the remote changeset must first
12546
** be applied to the local database using sqlite3changeset_apply_v2() and
12547
** the buffer of rebase information captured. Then:
12548
**
12549
** <ol>
12550
**   <li> An sqlite3_rebaser object is created by calling
12551
**        sqlite3rebaser_create().
12552
**   <li> The new object is configured with the rebase buffer obtained from
12553
**        sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure().
12554
**        If the local changeset is to be rebased against multiple remote
12555
**        changesets, then sqlite3rebaser_configure() should be called
12556
**        multiple times, in the same order that the multiple
12557
**        sqlite3changeset_apply_v2() calls were made.
12558
**   <li> Each local changeset is rebased by calling sqlite3rebaser_rebase().
12559
**   <li> The sqlite3_rebaser object is deleted by calling
12560
**        sqlite3rebaser_delete().
12561
** </ol>
12562
*/
12563
typedef struct sqlite3_rebaser sqlite3_rebaser;
12564
12565
/*
12566
** CAPI3REF: Create a changeset rebaser object.
12567
** EXPERIMENTAL
12568
**
12569
** Allocate a new changeset rebaser object. If successful, set (*ppNew) to
12570
** point to the new object and return SQLITE_OK. Otherwise, if an error
12571
** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew)
12572
** to NULL.
12573
*/
12574
SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew);
12575
12576
/*
12577
** CAPI3REF: Configure a changeset rebaser object.
12578
** EXPERIMENTAL
12579
**
12580
** Configure the changeset rebaser object to rebase changesets according
12581
** to the conflict resolutions described by buffer pRebase (size nRebase
12582
** bytes), which must have been obtained from a previous call to
12583
** sqlite3changeset_apply_v2().
12584
*/
12585
SQLITE_API int sqlite3rebaser_configure(
12586
  sqlite3_rebaser*,
12587
  int nRebase, const void *pRebase
12588
);
12589
12590
/*
12591
** CAPI3REF: Rebase a changeset
12592
** EXPERIMENTAL
12593
**
12594
** Argument pIn must point to a buffer containing a changeset nIn bytes
12595
** in size. This function allocates and populates a buffer with a copy
12596
** of the changeset rebased according to the configuration of the
12597
** rebaser object passed as the first argument. If successful, (*ppOut)
12598
** is set to point to the new buffer containing the rebased changeset and
12599
** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the
12600
** responsibility of the caller to eventually free the new buffer using
12601
** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut)
12602
** are set to zero and an SQLite error code returned.
12603
*/
12604
SQLITE_API int sqlite3rebaser_rebase(
12605
  sqlite3_rebaser*,
12606
  int nIn, const void *pIn,
12607
  int *pnOut, void **ppOut
12608
);
12609
12610
/*
12611
** CAPI3REF: Delete a changeset rebaser object.
12612
** EXPERIMENTAL
12613
**
12614
** Delete the changeset rebaser object and all associated resources. There
12615
** should be one call to this function for each successful invocation
12616
** of sqlite3rebaser_create().
12617
*/
12618
SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p);
12619
12620
/*
12621
** CAPI3REF: Streaming Versions of API functions.
12622
**
12623
** The six streaming API xxx_strm() functions serve similar purposes to the
12624
** corresponding non-streaming API functions:
12625
**
12626
** <table border=1 style="margin-left:8ex;margin-right:8ex">
12627
**   <tr><th>Streaming function<th>Non-streaming equivalent</th>
12628
**   <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply]
12629
**   <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2]
12630
**   <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat]
12631
**   <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert]
12632
**   <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start]
12633
**   <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset]
12634
**   <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset]
12635
** </table>
12636
**
12637
** Non-streaming functions that accept changesets (or patchsets) as input
12638
** require that the entire changeset be stored in a single buffer in memory.
12639
** Similarly, those that return a changeset or patchset do so by returning
12640
** a pointer to a single large buffer allocated using sqlite3_malloc().
12641
** Normally this is convenient. However, if an application running in a
12642
** low-memory environment is required to handle very large changesets, the
12643
** large contiguous memory allocations required can become onerous.
12644
**
12645
** In order to avoid this problem, instead of a single large buffer, input
12646
** is passed to a streaming API functions by way of a callback function that
12647
** the sessions module invokes to incrementally request input data as it is
12648
** required. In all cases, a pair of API function parameters such as
12649
**
12650
**  <pre>
12651
**  &nbsp;     int nChangeset,
12652
**  &nbsp;     void *pChangeset,
12653
**  </pre>
12654
**
12655
** Is replaced by:
12656
**
12657
**  <pre>
12658
**  &nbsp;     int (*xInput)(void *pIn, void *pData, int *pnData),
12659
**  &nbsp;     void *pIn,
12660
**  </pre>
12661
**
12662
** Each time the xInput callback is invoked by the sessions module, the first
12663
** argument passed is a copy of the supplied pIn context pointer. The second
12664
** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
12665
** error occurs the xInput method should copy up to (*pnData) bytes of data
12666
** into the buffer and set (*pnData) to the actual number of bytes copied
12667
** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
12668
** should be set to zero to indicate this. Or, if an error occurs, an SQLite
12669
** error code should be returned. In all cases, if an xInput callback returns
12670
** an error, all processing is abandoned and the streaming API function
12671
** returns a copy of the error code to the caller.
12672
**
12673
** In the case of sqlite3changeset_start_strm(), the xInput callback may be
12674
** invoked by the sessions module at any point during the lifetime of the
12675
** iterator. If such an xInput callback returns an error, the iterator enters
12676
** an error state, whereby all subsequent calls to iterator functions
12677
** immediately fail with the same error code as returned by xInput.
12678
**
12679
** Similarly, streaming API functions that return changesets (or patchsets)
12680
** return them in chunks by way of a callback function instead of via a
12681
** pointer to a single large buffer. In this case, a pair of parameters such
12682
** as:
12683
**
12684
**  <pre>
12685
**  &nbsp;     int *pnChangeset,
12686
**  &nbsp;     void **ppChangeset,
12687
**  </pre>
12688
**
12689
** Is replaced by:
12690
**
12691
**  <pre>
12692
**  &nbsp;     int (*xOutput)(void *pOut, const void *pData, int nData),
12693
**  &nbsp;     void *pOut
12694
**  </pre>
12695
**
12696
** The xOutput callback is invoked zero or more times to return data to
12697
** the application. The first parameter passed to each call is a copy of the
12698
** pOut pointer supplied by the application. The second parameter, pData,
12699
** points to a buffer nData bytes in size containing the chunk of output
12700
** data being returned. If the xOutput callback successfully processes the
12701
** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
12702
** it should return some other SQLite error code. In this case processing
12703
** is immediately abandoned and the streaming API function returns a copy
12704
** of the xOutput error code to the application.
12705
**
12706
** The sessions module never invokes an xOutput callback with the third
12707
** parameter set to a value less than or equal to zero. Other than this,
12708
** no guarantees are made as to the size of the chunks of data returned.
12709
*/
12710
SQLITE_API int sqlite3changeset_apply_strm(
12711
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12712
  int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
12713
  void *pIn,                                          /* First arg for xInput */
12714
  int(*xFilter)(
12715
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12716
    const char *zTab              /* Table name */
12717
  ),
12718
  int(*xConflict)(
12719
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12720
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12721
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12722
  ),
12723
  void *pCtx                      /* First argument passed to xConflict */
12724
);
12725
SQLITE_API int sqlite3changeset_apply_v2_strm(
12726
  sqlite3 *db,                    /* Apply change to "main" db of this handle */
12727
  int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
12728
  void *pIn,                                          /* First arg for xInput */
12729
  int(*xFilter)(
12730
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12731
    const char *zTab              /* Table name */
12732
  ),
12733
  int(*xConflict)(
12734
    void *pCtx,                   /* Copy of sixth arg to _apply() */
12735
    int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
12736
    sqlite3_changeset_iter *p     /* Handle describing change and conflict */
12737
  ),
12738
  void *pCtx,                     /* First argument passed to xConflict */
12739
  void **ppRebase, int *pnRebase,
12740
  int flags
12741
);
12742
SQLITE_API int sqlite3changeset_concat_strm(
12743
  int (*xInputA)(void *pIn, void *pData, int *pnData),
12744
  void *pInA,
12745
  int (*xInputB)(void *pIn, void *pData, int *pnData),
12746
  void *pInB,
12747
  int (*xOutput)(void *pOut, const void *pData, int nData),
12748
  void *pOut
12749
);
12750
SQLITE_API int sqlite3changeset_invert_strm(
12751
  int (*xInput)(void *pIn, void *pData, int *pnData),
12752
  void *pIn,
12753
  int (*xOutput)(void *pOut, const void *pData, int nData),
12754
  void *pOut
12755
);
12756
SQLITE_API int sqlite3changeset_start_strm(
12757
  sqlite3_changeset_iter **pp,
12758
  int (*xInput)(void *pIn, void *pData, int *pnData),
12759
  void *pIn
12760
);
12761
SQLITE_API int sqlite3changeset_start_v2_strm(
12762
  sqlite3_changeset_iter **pp,
12763
  int (*xInput)(void *pIn, void *pData, int *pnData),
12764
  void *pIn,
12765
  int flags
12766
);
12767
SQLITE_API int sqlite3session_changeset_strm(
12768
  sqlite3_session *pSession,
12769
  int (*xOutput)(void *pOut, const void *pData, int nData),
12770
  void *pOut
12771
);
12772
SQLITE_API int sqlite3session_patchset_strm(
12773
  sqlite3_session *pSession,
12774
  int (*xOutput)(void *pOut, const void *pData, int nData),
12775
  void *pOut
12776
);
12777
SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
12778
    int (*xInput)(void *pIn, void *pData, int *pnData),
12779
    void *pIn
12780
);
12781
SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
12782
    int (*xOutput)(void *pOut, const void *pData, int nData),
12783
    void *pOut
12784
);
12785
SQLITE_API int sqlite3rebaser_rebase_strm(
12786
  sqlite3_rebaser *pRebaser,
12787
  int (*xInput)(void *pIn, void *pData, int *pnData),
12788
  void *pIn,
12789
  int (*xOutput)(void *pOut, const void *pData, int nData),
12790
  void *pOut
12791
);
12792
12793
/*
12794
** CAPI3REF: Configure global parameters
12795
**
12796
** The sqlite3session_config() interface is used to make global configuration
12797
** changes to the sessions module in order to tune it to the specific needs
12798
** of the application.
12799
**
12800
** The sqlite3session_config() interface is not threadsafe. If it is invoked
12801
** while any other thread is inside any other sessions method then the
12802
** results are undefined. Furthermore, if it is invoked after any sessions
12803
** related objects have been created, the results are also undefined.
12804
**
12805
** The first argument to the sqlite3session_config() function must be one
12806
** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The
12807
** interpretation of the (void*) value passed as the second parameter and
12808
** the effect of calling this function depends on the value of the first
12809
** parameter.
12810
**
12811
** <dl>
12812
** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd>
12813
**    By default, the sessions module streaming interfaces attempt to input
12814
**    and output data in approximately 1 KiB chunks. This operand may be used
12815
**    to set and query the value of this configuration setting. The pointer
12816
**    passed as the second argument must point to a value of type (int).
12817
**    If this value is greater than 0, it is used as the new streaming data
12818
**    chunk size for both input and output. Before returning, the (int) value
12819
**    pointed to by pArg is set to the final value of the streaming interface
12820
**    chunk size.
12821
** </dl>
12822
**
12823
** This function returns SQLITE_OK if successful, or an SQLite error code
12824
** otherwise.
12825
*/
12826
SQLITE_API int sqlite3session_config(int op, void *pArg);
12827
12828
/*
12829
** CAPI3REF: Values for sqlite3session_config().
12830
*/
12831
#define SQLITE_SESSION_CONFIG_STRMSIZE 1
12832
12833
/*
12834
** Make sure we can call this stuff from C++.
12835
*/
12836
#ifdef __cplusplus
12837
}
12838
#endif
12839
12840
#endif  /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
12841
12842
/******** End of sqlite3session.h *********/
12843
/******** Begin file fts5.h *********/
12844
/*
12845
** 2014 May 31
12846
**
12847
** The author disclaims copyright to this source code.  In place of
12848
** a legal notice, here is a blessing:
12849
**
12850
**    May you do good and not evil.
12851
**    May you find forgiveness for yourself and forgive others.
12852
**    May you share freely, never taking more than you give.
12853
**
12854
******************************************************************************
12855
**
12856
** Interfaces to extend FTS5. Using the interfaces defined in this file,
12857
** FTS5 may be extended with:
12858
**
12859
**     * custom tokenizers, and
12860
**     * custom auxiliary functions.
12861
*/
12862
12863
12864
#ifndef _FTS5_H
12865
#define _FTS5_H
12866
12867
12868
#ifdef __cplusplus
12869
extern "C" {
12870
#endif
12871
12872
/*************************************************************************
12873
** CUSTOM AUXILIARY FUNCTIONS
12874
**
12875
** Virtual table implementations may overload SQL functions by implementing
12876
** the sqlite3_module.xFindFunction() method.
12877
*/
12878
12879
typedef struct Fts5ExtensionApi Fts5ExtensionApi;
12880
typedef struct Fts5Context Fts5Context;
12881
typedef struct Fts5PhraseIter Fts5PhraseIter;
12882
12883
typedef void (*fts5_extension_function)(
12884
  const Fts5ExtensionApi *pApi,   /* API offered by current FTS version */
12885
  Fts5Context *pFts,              /* First arg to pass to pApi functions */
12886
  sqlite3_context *pCtx,          /* Context for returning result/error */
12887
  int nVal,                       /* Number of values in apVal[] array */
12888
  sqlite3_value **apVal           /* Array of trailing arguments */
12889
);
12890
12891
struct Fts5PhraseIter {
12892
  const unsigned char *a;
12893
  const unsigned char *b;
12894
};
12895
12896
/*
12897
** EXTENSION API FUNCTIONS
12898
**
12899
** xUserData(pFts):
12900
**   Return a copy of the pUserData pointer passed to the xCreateFunction()
12901
**   API when the extension function was registered.
12902
**
12903
** xColumnTotalSize(pFts, iCol, pnToken):
12904
**   If parameter iCol is less than zero, set output variable *pnToken
12905
**   to the total number of tokens in the FTS5 table. Or, if iCol is
12906
**   non-negative but less than the number of columns in the table, return
12907
**   the total number of tokens in column iCol, considering all rows in
12908
**   the FTS5 table.
12909
**
12910
**   If parameter iCol is greater than or equal to the number of columns
12911
**   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
12912
**   an OOM condition or IO error), an appropriate SQLite error code is
12913
**   returned.
12914
**
12915
** xColumnCount(pFts):
12916
**   Return the number of columns in the table.
12917
**
12918
** xColumnSize(pFts, iCol, pnToken):
12919
**   If parameter iCol is less than zero, set output variable *pnToken
12920
**   to the total number of tokens in the current row. Or, if iCol is
12921
**   non-negative but less than the number of columns in the table, set
12922
**   *pnToken to the number of tokens in column iCol of the current row.
12923
**
12924
**   If parameter iCol is greater than or equal to the number of columns
12925
**   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
12926
**   an OOM condition or IO error), an appropriate SQLite error code is
12927
**   returned.
12928
**
12929
**   This function may be quite inefficient if used with an FTS5 table
12930
**   created with the "columnsize=0" option.
12931
**
12932
** xColumnText:
12933
**   If parameter iCol is less than zero, or greater than or equal to the
12934
**   number of columns in the table, SQLITE_RANGE is returned.
12935
**
12936
**   Otherwise, this function attempts to retrieve the text of column iCol of
12937
**   the current document. If successful, (*pz) is set to point to a buffer
12938
**   containing the text in utf-8 encoding, (*pn) is set to the size in bytes
12939
**   (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
12940
**   if an error occurs, an SQLite error code is returned and the final values
12941
**   of (*pz) and (*pn) are undefined.
12942
**
12943
** xPhraseCount:
12944
**   Returns the number of phrases in the current query expression.
12945
**
12946
** xPhraseSize:
12947
**   If parameter iCol is less than zero, or greater than or equal to the
12948
**   number of phrases in the current query, as returned by xPhraseCount,
12949
**   0 is returned. Otherwise, this function returns the number of tokens in
12950
**   phrase iPhrase of the query. Phrases are numbered starting from zero.
12951
**
12952
** xInstCount:
12953
**   Set *pnInst to the total number of occurrences of all phrases within
12954
**   the query within the current row. Return SQLITE_OK if successful, or
12955
**   an error code (i.e. SQLITE_NOMEM) if an error occurs.
12956
**
12957
**   This API can be quite slow if used with an FTS5 table created with the
12958
**   "detail=none" or "detail=column" option. If the FTS5 table is created
12959
**   with either "detail=none" or "detail=column" and "content=" option
12960
**   (i.e. if it is a contentless table), then this API always returns 0.
12961
**
12962
** xInst:
12963
**   Query for the details of phrase match iIdx within the current row.
12964
**   Phrase matches are numbered starting from zero, so the iIdx argument
12965
**   should be greater than or equal to zero and smaller than the value
12966
**   output by xInstCount(). If iIdx is less than zero or greater than
12967
**   or equal to the value returned by xInstCount(), SQLITE_RANGE is returned.
12968
**
12969
**   Otherwise, output parameter *piPhrase is set to the phrase number, *piCol
12970
**   to the column in which it occurs and *piOff the token offset of the
12971
**   first token of the phrase. SQLITE_OK is returned if successful, or an
12972
**   error code (i.e. SQLITE_NOMEM) if an error occurs.
12973
**
12974
**   This API can be quite slow if used with an FTS5 table created with the
12975
**   "detail=none" or "detail=column" option.
12976
**
12977
** xRowid:
12978
**   Returns the rowid of the current row.
12979
**
12980
** xTokenize:
12981
**   Tokenize text using the tokenizer belonging to the FTS5 table.
12982
**
12983
** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
12984
**   This API function is used to query the FTS table for phrase iPhrase
12985
**   of the current query. Specifically, a query equivalent to:
12986
**
12987
**       ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
12988
**
12989
**   with $p set to a phrase equivalent to the phrase iPhrase of the
12990
**   current query is executed. Any column filter that applies to
12991
**   phrase iPhrase of the current query is included in $p. For each
12992
**   row visited, the callback function passed as the fourth argument
12993
**   is invoked. The context and API objects passed to the callback
12994
**   function may be used to access the properties of each matched row.
12995
**   Invoking Api.xUserData() returns a copy of the pointer passed as
12996
**   the third argument to pUserData.
12997
**
12998
**   If parameter iPhrase is less than zero, or greater than or equal to
12999
**   the number of phrases in the query, as returned by xPhraseCount(),
13000
**   this function returns SQLITE_RANGE.
13001
**
13002
**   If the callback function returns any value other than SQLITE_OK, the
13003
**   query is abandoned and the xQueryPhrase function returns immediately.
13004
**   If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
13005
**   Otherwise, the error code is propagated upwards.
13006
**
13007
**   If the query runs to completion without incident, SQLITE_OK is returned.
13008
**   Or, if some error occurs before the query completes or is aborted by
13009
**   the callback, an SQLite error code is returned.
13010
**
13011
**
13012
** xSetAuxdata(pFts5, pAux, xDelete)
13013
**
13014
**   Save the pointer passed as the second argument as the extension function's
13015
**   "auxiliary data". The pointer may then be retrieved by the current or any
13016
**   future invocation of the same fts5 extension function made as part of
13017
**   the same MATCH query using the xGetAuxdata() API.
13018
**
13019
**   Each extension function is allocated a single auxiliary data slot for
13020
**   each FTS query (MATCH expression). If the extension function is invoked
13021
**   more than once for a single FTS query, then all invocations share a
13022
**   single auxiliary data context.
13023
**
13024
**   If there is already an auxiliary data pointer when this function is
13025
**   invoked, then it is replaced by the new pointer. If an xDelete callback
13026
**   was specified along with the original pointer, it is invoked at this
13027
**   point.
13028
**
13029
**   The xDelete callback, if one is specified, is also invoked on the
13030
**   auxiliary data pointer after the FTS5 query has finished.
13031
**
13032
**   If an error (e.g. an OOM condition) occurs within this function,
13033
**   the auxiliary data is set to NULL and an error code returned. If the
13034
**   xDelete parameter was not NULL, it is invoked on the auxiliary data
13035
**   pointer before returning.
13036
**
13037
**
13038
** xGetAuxdata(pFts5, bClear)
13039
**
13040
**   Returns the current auxiliary data pointer for the fts5 extension
13041
**   function. See the xSetAuxdata() method for details.
13042
**
13043
**   If the bClear argument is non-zero, then the auxiliary data is cleared
13044
**   (set to NULL) before this function returns. In this case the xDelete,
13045
**   if any, is not invoked.
13046
**
13047
**
13048
** xRowCount(pFts5, pnRow)
13049
**
13050
**   This function is used to retrieve the total number of rows in the table.
13051
**   In other words, the same value that would be returned by:
13052
**
13053
**        SELECT count(*) FROM ftstable;
13054
**
13055
** xPhraseFirst()
13056
**   This function is used, along with type Fts5PhraseIter and the xPhraseNext
13057
**   method, to iterate through all instances of a single query phrase within
13058
**   the current row. This is the same information as is accessible via the
13059
**   xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
13060
**   to use, this API may be faster under some circumstances. To iterate
13061
**   through instances of phrase iPhrase, use the following code:
13062
**
13063
**       Fts5PhraseIter iter;
13064
**       int iCol, iOff;
13065
**       for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
13066
**           iCol>=0;
13067
**           pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
13068
**       ){
13069
**         // An instance of phrase iPhrase at offset iOff of column iCol
13070
**       }
13071
**
13072
**   The Fts5PhraseIter structure is defined above. Applications should not
13073
**   modify this structure directly - it should only be used as shown above
13074
**   with the xPhraseFirst() and xPhraseNext() API methods (and by
13075
**   xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
13076
**
13077
**   This API can be quite slow if used with an FTS5 table created with the
13078
**   "detail=none" or "detail=column" option. If the FTS5 table is created
13079
**   with either "detail=none" or "detail=column" and "content=" option
13080
**   (i.e. if it is a contentless table), then this API always iterates
13081
**   through an empty set (all calls to xPhraseFirst() set iCol to -1).
13082
**
13083
**   In all cases, matches are visited in (column ASC, offset ASC) order.
13084
**   i.e. all those in column 0, sorted by offset, followed by those in
13085
**   column 1, etc.
13086
**
13087
** xPhraseNext()
13088
**   See xPhraseFirst above.
13089
**
13090
** xPhraseFirstColumn()
13091
**   This function and xPhraseNextColumn() are similar to the xPhraseFirst()
13092
**   and xPhraseNext() APIs described above. The difference is that instead
13093
**   of iterating through all instances of a phrase in the current row, these
13094
**   APIs are used to iterate through the set of columns in the current row
13095
**   that contain one or more instances of a specified phrase. For example:
13096
**
13097
**       Fts5PhraseIter iter;
13098
**       int iCol;
13099
**       for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
13100
**           iCol>=0;
13101
**           pApi->xPhraseNextColumn(pFts, &iter, &iCol)
13102
**       ){
13103
**         // Column iCol contains at least one instance of phrase iPhrase
13104
**       }
13105
**
13106
**   This API can be quite slow if used with an FTS5 table created with the
13107
**   "detail=none" option. If the FTS5 table is created with either
13108
**   "detail=none" "content=" option (i.e. if it is a contentless table),
13109
**   then this API always iterates through an empty set (all calls to
13110
**   xPhraseFirstColumn() set iCol to -1).
13111
**
13112
**   The information accessed using this API and its companion
13113
**   xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
13114
**   (or xInst/xInstCount). The chief advantage of this API is that it is
13115
**   significantly more efficient than those alternatives when used with
13116
**   "detail=column" tables.
13117
**
13118
** xPhraseNextColumn()
13119
**   See xPhraseFirstColumn above.
13120
**
13121
** xQueryToken(pFts5, iPhrase, iToken, ppToken, pnToken)
13122
**   This is used to access token iToken of phrase iPhrase of the current
13123
**   query. Before returning, output parameter *ppToken is set to point
13124
**   to a buffer containing the requested token, and *pnToken to the
13125
**   size of this buffer in bytes.
13126
**
13127
**   If iPhrase or iToken are less than zero, or if iPhrase is greater than
13128
**   or equal to the number of phrases in the query as reported by
13129
**   xPhraseCount(), or if iToken is equal to or greater than the number of
13130
**   tokens in the phrase, SQLITE_RANGE is returned and *ppToken and *pnToken
13131
     are both zeroed.
13132
**
13133
**   The output text is not a copy of the query text that specified the
13134
**   token. It is the output of the tokenizer module. For tokendata=1
13135
**   tables, this includes any embedded 0x00 and trailing data.
13136
**
13137
** xInstToken(pFts5, iIdx, iToken, ppToken, pnToken)
13138
**   This is used to access token iToken of phrase hit iIdx within the
13139
**   current row. If iIdx is less than zero or greater than or equal to the
13140
**   value returned by xInstCount(), SQLITE_RANGE is returned.  Otherwise,
13141
**   output variable (*ppToken) is set to point to a buffer containing the
13142
**   matching document token, and (*pnToken) to the size of that buffer in
13143
**   bytes. This API is not available if the specified token matches a
13144
**   prefix query term. In that case both output variables are always set
13145
**   to 0.
13146
**
13147
**   The output text is not a copy of the document text that was tokenized.
13148
**   It is the output of the tokenizer module. For tokendata=1 tables, this
13149
**   includes any embedded 0x00 and trailing data.
13150
**
13151
**   This API can be quite slow if used with an FTS5 table created with the
13152
**   "detail=none" or "detail=column" option.
13153
**
13154
** xColumnLocale(pFts5, iIdx, pzLocale, pnLocale)
13155
**   If parameter iCol is less than zero, or greater than or equal to the
13156
**   number of columns in the table, SQLITE_RANGE is returned.
13157
**
13158
**   Otherwise, this function attempts to retrieve the locale associated
13159
**   with column iCol of the current row. Usually, there is no associated
13160
**   locale, and output parameters (*pzLocale) and (*pnLocale) are set
13161
**   to NULL and 0, respectively. However, if the fts5_locale() function
13162
**   was used to associate a locale with the value when it was inserted
13163
**   into the fts5 table, then (*pzLocale) is set to point to a nul-terminated
13164
**   buffer containing the name of the locale in utf-8 encoding. (*pnLocale)
13165
**   is set to the size in bytes of the buffer, not including the
13166
**   nul-terminator.
13167
**
13168
**   If successful, SQLITE_OK is returned. Or, if an error occurs, an
13169
**   SQLite error code is returned. The final value of the output parameters
13170
**   is undefined in this case.
13171
**
13172
** xTokenize_v2:
13173
**   Tokenize text using the tokenizer belonging to the FTS5 table. This
13174
**   API is the same as the xTokenize() API, except that it allows a tokenizer
13175
**   locale to be specified.
13176
*/
13177
struct Fts5ExtensionApi {
13178
  int iVersion;                   /* Currently always set to 4 */
13179
13180
  void *(*xUserData)(Fts5Context*);
13181
13182
  int (*xColumnCount)(Fts5Context*);
13183
  int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
13184
  int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
13185
13186
  int (*xTokenize)(Fts5Context*,
13187
    const char *pText, int nText, /* Text to tokenize */
13188
    void *pCtx,                   /* Context passed to xToken() */
13189
    int (*xToken)(void*, int, const char*, int, int, int)       /* Callback */
13190
  );
13191
13192
  int (*xPhraseCount)(Fts5Context*);
13193
  int (*xPhraseSize)(Fts5Context*, int iPhrase);
13194
13195
  int (*xInstCount)(Fts5Context*, int *pnInst);
13196
  int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
13197
13198
  sqlite3_int64 (*xRowid)(Fts5Context*);
13199
  int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
13200
  int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
13201
13202
  int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
13203
    int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
13204
  );
13205
  int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
13206
  void *(*xGetAuxdata)(Fts5Context*, int bClear);
13207
13208
  int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
13209
  void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
13210
13211
  int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
13212
  void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
13213
13214
  /* Below this point are iVersion>=3 only */
13215
  int (*xQueryToken)(Fts5Context*,
13216
      int iPhrase, int iToken,
13217
      const char **ppToken, int *pnToken
13218
  );
13219
  int (*xInstToken)(Fts5Context*, int iIdx, int iToken, const char**, int*);
13220
13221
  /* Below this point are iVersion>=4 only */
13222
  int (*xColumnLocale)(Fts5Context*, int iCol, const char **pz, int *pn);
13223
  int (*xTokenize_v2)(Fts5Context*,
13224
    const char *pText, int nText,      /* Text to tokenize */
13225
    const char *pLocale, int nLocale,  /* Locale to pass to tokenizer */
13226
    void *pCtx,                        /* Context passed to xToken() */
13227
    int (*xToken)(void*, int, const char*, int, int, int)       /* Callback */
13228
  );
13229
};
13230
13231
/*
13232
** CUSTOM AUXILIARY FUNCTIONS
13233
*************************************************************************/
13234
13235
/*************************************************************************
13236
** CUSTOM TOKENIZERS
13237
**
13238
** Applications may also register custom tokenizer types. A tokenizer
13239
** is registered by providing fts5 with a populated instance of the
13240
** following structure. All structure methods must be defined, setting
13241
** any member of the fts5_tokenizer struct to NULL leads to undefined
13242
** behaviour. The structure methods are expected to function as follows:
13243
**
13244
** xCreate:
13245
**   This function is used to allocate and initialize a tokenizer instance.
13246
**   A tokenizer instance is required to actually tokenize text.
13247
**
13248
**   The first argument passed to this function is a copy of the (void*)
13249
**   pointer provided by the application when the fts5_tokenizer_v2 object
13250
**   was registered with FTS5 (the third argument to xCreateTokenizer()).
13251
**   The second and third arguments are an array of nul-terminated strings
13252
**   containing the tokenizer arguments, if any, specified following the
13253
**   tokenizer name as part of the CREATE VIRTUAL TABLE statement used
13254
**   to create the FTS5 table.
13255
**
13256
**   The final argument is an output variable. If successful, (*ppOut)
13257
**   should be set to point to the new tokenizer handle and SQLITE_OK
13258
**   returned. If an error occurs, some value other than SQLITE_OK should
13259
**   be returned. In this case, fts5 assumes that the final value of *ppOut
13260
**   is undefined.
13261
**
13262
** xDelete:
13263
**   This function is invoked to delete a tokenizer handle previously
13264
**   allocated using xCreate(). Fts5 guarantees that this function will
13265
**   be invoked exactly once for each successful call to xCreate().
13266
**
13267
** xTokenize:
13268
**   This function is expected to tokenize the nText byte string indicated
13269
**   by argument pText. pText may or may not be nul-terminated. The first
13270
**   argument passed to this function is a pointer to an Fts5Tokenizer object
13271
**   returned by an earlier call to xCreate().
13272
**
13273
**   The third argument indicates the reason that FTS5 is requesting
13274
**   tokenization of the supplied text. This is always one of the following
13275
**   four values:
13276
**
13277
**   <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
13278
**            or removed from the FTS table. The tokenizer is being invoked to
13279
**            determine the set of tokens to add to (or delete from) the
13280
**            FTS index.
13281
**
13282
**       <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
13283
**            against the FTS index. The tokenizer is being called to tokenize
13284
**            a bareword or quoted string specified as part of the query.
13285
**
13286
**       <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
13287
**            FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
13288
**            followed by a "*" character, indicating that the last token
13289
**            returned by the tokenizer will be treated as a token prefix.
13290
**
13291
**       <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
13292
**            satisfy an fts5_api.xTokenize() request made by an auxiliary
13293
**            function. Or an fts5_api.xColumnSize() request made by the same
13294
**            on a columnsize=0 database.
13295
**   </ul>
13296
**
13297
**   The sixth and seventh arguments passed to xTokenize() - pLocale and
13298
**   nLocale - are a pointer to a buffer containing the locale to use for
13299
**   tokenization (e.g. "en_US") and its size in bytes, respectively. The
13300
**   pLocale buffer is not nul-terminated. pLocale may be passed NULL (in
13301
**   which case nLocale is always 0) to indicate that the tokenizer should
13302
**   use its default locale.
13303
**
13304
**   For each token in the input string, the supplied callback xToken() must
13305
**   be invoked. The first argument to it should be a copy of the pointer
13306
**   passed as the second argument to xTokenize(). The third and fourth
13307
**   arguments are a pointer to a buffer containing the token text, and the
13308
**   size of the token in bytes. The 4th and 5th arguments are the byte offsets
13309
**   of the first byte of and first byte immediately following the text from
13310
**   which the token is derived within the input.
13311
**
13312
**   The second argument passed to the xToken() callback ("tflags") should
13313
**   normally be set to 0. The exception is if the tokenizer supports
13314
**   synonyms. In this case see the discussion below for details.
13315
**
13316
**   FTS5 assumes the xToken() callback is invoked for each token in the
13317
**   order that they occur within the input text.
13318
**
13319
**   If an xToken() callback returns any value other than SQLITE_OK, then
13320
**   the tokenization should be abandoned and the xTokenize() method should
13321
**   immediately return a copy of the xToken() return value. Or, if the
13322
**   input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
13323
**   if an error occurs with the xTokenize() implementation itself, it
13324
**   may abandon the tokenization and return any error code other than
13325
**   SQLITE_OK or SQLITE_DONE.
13326
**
13327
**   If the tokenizer is registered using an fts5_tokenizer_v2 object,
13328
**   then the xTokenize() method has two additional arguments - pLocale
13329
**   and nLocale. These specify the locale that the tokenizer should use
13330
**   for the current request. If pLocale and nLocale are both 0, then the
13331
**   tokenizer should use its default locale. Otherwise, pLocale points to
13332
**   an nLocale byte buffer containing the name of the locale to use as utf-8
13333
**   text. pLocale is not nul-terminated.
13334
**
13335
** FTS5_TOKENIZER
13336
**
13337
** There is also an fts5_tokenizer object. This is an older, deprecated,
13338
** version of fts5_tokenizer_v2. It is similar except that:
13339
**
13340
**  <ul>
13341
**    <li> There is no "iVersion" field, and
13342
**    <li> The xTokenize() method does not take a locale argument.
13343
**  </ul>
13344
**
13345
** Legacy fts5_tokenizer tokenizers must be registered using the
13346
** legacy xCreateTokenizer() function, instead of xCreateTokenizer_v2().
13347
**
13348
** Tokenizer implementations registered using either API may be retrieved
13349
** using both xFindTokenizer() and xFindTokenizer_v2().
13350
**
13351
** SYNONYM SUPPORT
13352
**
13353
**   Custom tokenizers may also support synonyms. Consider a case in which a
13354
**   user wishes to query for a phrase such as "first place". Using the
13355
**   built-in tokenizers, the FTS5 query 'first + place' will match instances
13356
**   of "first place" within the document set, but not alternative forms
13357
**   such as "1st place". In some applications, it would be better to match
13358
**   all instances of "first place" or "1st place" regardless of which form
13359
**   the user specified in the MATCH query text.
13360
**
13361
**   There are several ways to approach this in FTS5:
13362
**
13363
**   <ol><li> By mapping all synonyms to a single token. In this case, using
13364
**            the above example, this means that the tokenizer returns the
13365
**            same token for inputs "first" and "1st". Say that token is in
13366
**            fact "first", so that when the user inserts the document "I won
13367
**            1st place" entries are added to the index for tokens "i", "won",
13368
**            "first" and "place". If the user then queries for '1st + place',
13369
**            the tokenizer substitutes "first" for "1st" and the query works
13370
**            as expected.
13371
**
13372
**       <li> By querying the index for all synonyms of each query term
13373
**            separately. In this case, when tokenizing query text, the
13374
**            tokenizer may provide multiple synonyms for a single term
13375
**            within the document. FTS5 then queries the index for each
13376
**            synonym individually. For example, faced with the query:
13377
**
13378
**   <codeblock>
13379
**     ... MATCH 'first place'</codeblock>
13380
**
13381
**            the tokenizer offers both "1st" and "first" as synonyms for the
13382
**            first token in the MATCH query and FTS5 effectively runs a query
13383
**            similar to:
13384
**
13385
**   <codeblock>
13386
**     ... MATCH '(first OR 1st) place'</codeblock>
13387
**
13388
**            except that, for the purposes of auxiliary functions, the query
13389
**            still appears to contain just two phrases - "(first OR 1st)"
13390
**            being treated as a single phrase.
13391
**
13392
**       <li> By adding multiple synonyms for a single term to the FTS index.
13393
**            Using this method, when tokenizing document text, the tokenizer
13394
**            provides multiple synonyms for each token. So that when a
13395
**            document such as "I won first place" is tokenized, entries are
13396
**            added to the FTS index for "i", "won", "first", "1st" and
13397
**            "place".
13398
**
13399
**            This way, even if the tokenizer does not provide synonyms
13400
**            when tokenizing query text (it should not - to do so would be
13401
**            inefficient), it doesn't matter if the user queries for
13402
**            'first + place' or '1st + place', as there are entries in the
13403
**            FTS index corresponding to both forms of the first token.
13404
**   </ol>
13405
**
13406
**   Whether it is parsing document or query text, any call to xToken that
13407
**   specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
13408
**   is considered to supply a synonym for the previous token. For example,
13409
**   when parsing the document "I won first place", a tokenizer that supports
13410
**   synonyms would call xToken() 5 times, as follows:
13411
**
13412
**   <codeblock>
13413
**       xToken(pCtx, 0, "i",                      1,  0,  1);
13414
**       xToken(pCtx, 0, "won",                    3,  2,  5);
13415
**       xToken(pCtx, 0, "first",                  5,  6, 11);
13416
**       xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3,  6, 11);
13417
**       xToken(pCtx, 0, "place",                  5, 12, 17);
13418
**</codeblock>
13419
**
13420
**   It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
13421
**   xToken() is called. Multiple synonyms may be specified for a single token
13422
**   by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
13423
**   There is no limit to the number of synonyms that may be provided for a
13424
**   single token.
13425
**
13426
**   In many cases, method (1) above is the best approach. It does not add
13427
**   extra data to the FTS index or require FTS5 to query for multiple terms,
13428
**   so it is efficient in terms of disk space and query speed. However, it
13429
**   does not support prefix queries very well. If, as suggested above, the
13430
**   token "first" is substituted for "1st" by the tokenizer, then the query:
13431
**
13432
**   <codeblock>
13433
**     ... MATCH '1s*'</codeblock>
13434
**
13435
**   will not match documents that contain the token "1st" (as the tokenizer
13436
**   will probably not map "1s" to any prefix of "first").
13437
**
13438
**   For full prefix support, method (3) may be preferred. In this case,
13439
**   because the index contains entries for both "first" and "1st", prefix
13440
**   queries such as 'fi*' or '1s*' will match correctly. However, because
13441
**   extra entries are added to the FTS index, this method uses more space
13442
**   within the database.
13443
**
13444
**   Method (2) offers a midpoint between (1) and (3). Using this method,
13445
**   a query such as '1s*' will match documents that contain the literal
13446
**   token "1st", but not "first" (assuming the tokenizer is not able to
13447
**   provide synonyms for prefixes). However, a non-prefix query like '1st'
13448
**   will match against "1st" and "first". This method does not require
13449
**   extra disk space, as no extra entries are added to the FTS index.
13450
**   On the other hand, it may require more CPU cycles to run MATCH queries,
13451
**   as separate queries of the FTS index are required for each synonym.
13452
**
13453
**   When using methods (2) or (3), it is important that the tokenizer only
13454
**   provide synonyms when tokenizing document text (method (3)) or query
13455
**   text (method (2)), not both. Doing so will not cause any errors, but is
13456
**   inefficient.
13457
*/
13458
typedef struct Fts5Tokenizer Fts5Tokenizer;
13459
typedef struct fts5_tokenizer_v2 fts5_tokenizer_v2;
13460
struct fts5_tokenizer_v2 {
13461
  int iVersion;             /* Currently always 2 */
13462
13463
  int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
13464
  void (*xDelete)(Fts5Tokenizer*);
13465
  int (*xTokenize)(Fts5Tokenizer*,
13466
      void *pCtx,
13467
      int flags,            /* Mask of FTS5_TOKENIZE_* flags */
13468
      const char *pText, int nText,
13469
      const char *pLocale, int nLocale,
13470
      int (*xToken)(
13471
        void *pCtx,         /* Copy of 2nd argument to xTokenize() */
13472
        int tflags,         /* Mask of FTS5_TOKEN_* flags */
13473
        const char *pToken, /* Pointer to buffer containing token */
13474
        int nToken,         /* Size of token in bytes */
13475
        int iStart,         /* Byte offset of token within input text */
13476
        int iEnd            /* Byte offset of end of token within input text */
13477
      )
13478
  );
13479
};
13480
13481
/*
13482
** New code should use the fts5_tokenizer_v2 type to define tokenizer
13483
** implementations. The following type is included for legacy applications
13484
** that still use it.
13485
*/
13486
typedef struct fts5_tokenizer fts5_tokenizer;
13487
struct fts5_tokenizer {
13488
  int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
13489
  void (*xDelete)(Fts5Tokenizer*);
13490
  int (*xTokenize)(Fts5Tokenizer*,
13491
      void *pCtx,
13492
      int flags,            /* Mask of FTS5_TOKENIZE_* flags */
13493
      const char *pText, int nText,
13494
      int (*xToken)(
13495
        void *pCtx,         /* Copy of 2nd argument to xTokenize() */
13496
        int tflags,         /* Mask of FTS5_TOKEN_* flags */
13497
        const char *pToken, /* Pointer to buffer containing token */
13498
        int nToken,         /* Size of token in bytes */
13499
        int iStart,         /* Byte offset of token within input text */
13500
        int iEnd            /* Byte offset of end of token within input text */
13501
      )
13502
  );
13503
};
13504
13505
13506
/* Flags that may be passed as the third argument to xTokenize() */
13507
#define FTS5_TOKENIZE_QUERY     0x0001
13508
#define FTS5_TOKENIZE_PREFIX    0x0002
13509
#define FTS5_TOKENIZE_DOCUMENT  0x0004
13510
#define FTS5_TOKENIZE_AUX       0x0008
13511
13512
/* Flags that may be passed by the tokenizer implementation back to FTS5
13513
** as the third argument to the supplied xToken callback. */
13514
#define FTS5_TOKEN_COLOCATED    0x0001      /* Same position as prev. token */
13515
13516
/*
13517
** END OF CUSTOM TOKENIZERS
13518
*************************************************************************/
13519
13520
/*************************************************************************
13521
** FTS5 EXTENSION REGISTRATION API
13522
*/
13523
typedef struct fts5_api fts5_api;
13524
struct fts5_api {
13525
  int iVersion;                   /* Currently always set to 3 */
13526
13527
  /* Create a new tokenizer */
13528
  int (*xCreateTokenizer)(
13529
    fts5_api *pApi,
13530
    const char *zName,
13531
    void *pUserData,
13532
    fts5_tokenizer *pTokenizer,
13533
    void (*xDestroy)(void*)
13534
  );
13535
13536
  /* Find an existing tokenizer */
13537
  int (*xFindTokenizer)(
13538
    fts5_api *pApi,
13539
    const char *zName,
13540
    void **ppUserData,
13541
    fts5_tokenizer *pTokenizer
13542
  );
13543
13544
  /* Create a new auxiliary function */
13545
  int (*xCreateFunction)(
13546
    fts5_api *pApi,
13547
    const char *zName,
13548
    void *pUserData,
13549
    fts5_extension_function xFunction,
13550
    void (*xDestroy)(void*)
13551
  );
13552
13553
  /* APIs below this point are only available if iVersion>=3 */
13554
13555
  /* Create a new tokenizer */
13556
  int (*xCreateTokenizer_v2)(
13557
    fts5_api *pApi,
13558
    const char *zName,
13559
    void *pUserData,
13560
    fts5_tokenizer_v2 *pTokenizer,
13561
    void (*xDestroy)(void*)
13562
  );
13563
13564
  /* Find an existing tokenizer */
13565
  int (*xFindTokenizer_v2)(
13566
    fts5_api *pApi,
13567
    const char *zName,
13568
    void **ppUserData,
13569
    fts5_tokenizer_v2 **ppTokenizer
13570
  );
13571
};
13572
13573
/*
13574
** END OF REGISTRATION API
13575
*************************************************************************/
13576
13577
#ifdef __cplusplus
13578
}  /* end of the 'extern "C"' block */
13579
#endif
13580
13581
#endif /* _FTS5_H */
13582
13583
/******** End of fts5.h *********/