Coverage Report

Created: 2019-07-03 22:50

/home/liu/buildslave/linux-x64-runtests/build/lib/3rdparty/sqlite3/sqlite3.h
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/*
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** 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:
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**
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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,
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** or constant definition does not appear in this file, then it is
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** not a published API of SQLite, is subject to change without
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** notice, and should not be referenced by programs that use SQLite.
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**
18
** Some of the definitions that are in this file are marked as
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** "experimental".  Experimental interfaces are normally new
20
** features recently added to SQLite.  We do not anticipate changes
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** to experimental interfaces but reserve the right to make minor changes
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** if experience from use "in the wild" suggest such changes are prudent.
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**
24
** The official C-language API documentation for SQLite is derived
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** from comments in this file.  This file is the authoritative source
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** on how SQLite interfaces are supposed to operate.
27
**
28
** The name of this file under configuration management is "sqlite.h.in".
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** The makefile makes some minor changes to this file (such as inserting
30
** the version number) and changes its name to "sqlite3.h" as
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** 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 */
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37
/*
38
** Make sure we can call this stuff from C++.
39
*/
40
#ifdef __cplusplus
41
extern "C" {
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#endif
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44
45
/*
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** Provide the ability to override linkage features of the interface.
47
*/
48
#ifndef SQLITE_EXTERN
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# define SQLITE_EXTERN extern
50
#endif
51
#ifndef SQLITE_API
52
# define SQLITE_API
53
#endif
54
#ifndef SQLITE_CDECL
55
# define SQLITE_CDECL
56
#endif
57
#ifndef SQLITE_APICALL
58
# define SQLITE_APICALL
59
#endif
60
#ifndef SQLITE_STDCALL
61
# define SQLITE_STDCALL SQLITE_APICALL
62
#endif
63
#ifndef SQLITE_CALLBACK
64
# define SQLITE_CALLBACK
65
#endif
66
#ifndef SQLITE_SYSAPI
67
# define SQLITE_SYSAPI
68
#endif
69
70
/*
71
** These no-op macros are used in front of interfaces to mark those
72
** interfaces as either deprecated or experimental.  New applications
73
** should not use deprecated interfaces - they are supported for backwards
74
** compatibility only.  Application writers should be aware that
75
** experimental interfaces are subject to change in point releases.
76
**
77
** These macros used to resolve to various kinds of compiler magic that
78
** would generate warning messages when they were used.  But that
79
** compiler magic ended up generating such a flurry of bug reports
80
** that we have taken it all out and gone back to using simple
81
** noop macros.
82
*/
83
#define SQLITE_DEPRECATED
84
#define SQLITE_EXPERIMENTAL
85
86
/*
87
** Ensure these symbols were not defined by some previous header file.
88
*/
89
#ifdef SQLITE_VERSION
90
# undef SQLITE_VERSION
91
#endif
92
#ifdef SQLITE_VERSION_NUMBER
93
# undef SQLITE_VERSION_NUMBER
94
#endif
95
96
/*
97
** CAPI3REF: Compile-Time Library Version Numbers
98
**
99
** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
100
** evaluates to a string literal that is the SQLite version in the
101
** format "X.Y.Z" where X is the major version number (always 3 for
102
** SQLite3) and Y is the minor version number and Z is the release number.)^
103
** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
104
** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
105
** numbers used in [SQLITE_VERSION].)^
106
** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
107
** be larger than the release from which it is derived.  Either Y will
108
** be held constant and Z will be incremented or else Y will be incremented
109
** and Z will be reset to zero.
110
**
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** Since [version 3.6.18] ([dateof:3.6.18]), 
112
** SQLite source code has been stored in the
113
** <a href="http://www.fossil-scm.org/">Fossil configuration management
114
** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
115
** a string which identifies a particular check-in of SQLite
116
** within its configuration management system.  ^The SQLITE_SOURCE_ID
117
** string contains the date and time of the check-in (UTC) and a SHA1
118
** or SHA3-256 hash of the entire source tree.  If the source code has
119
** been edited in any way since it was last checked in, then the last
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** four hexadecimal digits of the hash may be modified.
121
**
122
** See also: [sqlite3_libversion()],
123
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
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** [sqlite_version()] and [sqlite_source_id()].
125
*/
126
#define SQLITE_VERSION        "3.23.1"
127
#define SQLITE_VERSION_NUMBER 3023001
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#define SQLITE_SOURCE_ID      "2018-04-10 17:39:29 4bb2294022060e61de7da5c227a69ccd846ba330e31626ebcd59a94efd148b3b"
129
130
/*
131
** CAPI3REF: Run-Time Library Version Numbers
132
** KEYWORDS: sqlite3_version sqlite3_sourceid
133
**
134
** These interfaces provide the same information as the [SQLITE_VERSION],
135
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
136
** but are associated with the library instead of the header file.  ^(Cautious
137
** programmers might include assert() statements in their application to
138
** verify that values returned by these interfaces match the macros in
139
** the header, and thus ensure that the application is
140
** compiled with matching library and header files.
141
**
142
** <blockquote><pre>
143
** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
144
** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
145
** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
146
** </pre></blockquote>)^
147
**
148
** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
149
** macro.  ^The sqlite3_libversion() function returns a pointer to the
150
** to the sqlite3_version[] string constant.  The sqlite3_libversion()
151
** function is provided for use in DLLs since DLL users usually do not have
152
** direct access to string constants within the DLL.  ^The
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** sqlite3_libversion_number() function returns an integer equal to
154
** [SQLITE_VERSION_NUMBER].  ^(The sqlite3_sourceid() function returns 
155
** a pointer to a string constant whose value is the same as the 
156
** [SQLITE_SOURCE_ID] C preprocessor macro.  Except if SQLite is built
157
** using an edited copy of [the amalgamation], then the last four characters
158
** of the hash might be different from [SQLITE_SOURCE_ID].)^
159
**
160
** See also: [sqlite_version()] and [sqlite_source_id()].
161
*/
162
SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
163
SQLITE_API const char *sqlite3_libversion(void);
164
SQLITE_API const char *sqlite3_sourceid(void);
165
SQLITE_API int sqlite3_libversion_number(void);
166
167
/*
168
** CAPI3REF: Run-Time Library Compilation Options Diagnostics
169
**
170
** ^The sqlite3_compileoption_used() function returns 0 or 1 
171
** indicating whether the specified option was defined at 
172
** compile time.  ^The SQLITE_ prefix may be omitted from the 
173
** option name passed to sqlite3_compileoption_used().  
174
**
175
** ^The sqlite3_compileoption_get() function allows iterating
176
** over the list of options that were defined at compile time by
177
** returning the N-th compile time option string.  ^If N is out of range,
178
** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_ 
179
** prefix is omitted from any strings returned by 
180
** sqlite3_compileoption_get().
181
**
182
** ^Support for the diagnostic functions sqlite3_compileoption_used()
183
** and sqlite3_compileoption_get() may be omitted by specifying the 
184
** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
185
**
186
** See also: SQL functions [sqlite_compileoption_used()] and
187
** [sqlite_compileoption_get()] and the [compile_options pragma].
188
*/
189
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
190
SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
191
SQLITE_API const char *sqlite3_compileoption_get(int N);
192
#endif
193
194
/*
195
** CAPI3REF: Test To See If The Library Is Threadsafe
196
**
197
** ^The sqlite3_threadsafe() function returns zero if and only if
198
** SQLite was compiled with mutexing code omitted due to the
199
** [SQLITE_THREADSAFE] compile-time option being set to 0.
200
**
201
** SQLite can be compiled with or without mutexes.  When
202
** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
203
** are enabled and SQLite is threadsafe.  When the
204
** [SQLITE_THREADSAFE] macro is 0, 
205
** the mutexes are omitted.  Without the mutexes, it is not safe
206
** to use SQLite concurrently from more than one thread.
207
**
208
** Enabling mutexes incurs a measurable performance penalty.
209
** So if speed is of utmost importance, it makes sense to disable
210
** the mutexes.  But for maximum safety, mutexes should be enabled.
211
** ^The default behavior is for mutexes to be enabled.
212
**
213
** This interface can be used by an application to make sure that the
214
** version of SQLite that it is linking against was compiled with
215
** the desired setting of the [SQLITE_THREADSAFE] macro.
216
**
217
** This interface only reports on the compile-time mutex setting
218
** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
219
** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
220
** can be fully or partially disabled using a call to [sqlite3_config()]
221
** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
222
** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
223
** sqlite3_threadsafe() function shows only the compile-time setting of
224
** thread safety, not any run-time changes to that setting made by
225
** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
226
** is unchanged by calls to sqlite3_config().)^
227
**
228
** See the [threading mode] documentation for additional information.
229
*/
230
SQLITE_API int sqlite3_threadsafe(void);
231
232
/*
233
** CAPI3REF: Database Connection Handle
234
** KEYWORDS: {database connection} {database connections}
235
**
236
** Each open SQLite database is represented by a pointer to an instance of
237
** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
238
** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
239
** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
240
** and [sqlite3_close_v2()] are its destructors.  There are many other
241
** interfaces (such as
242
** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
243
** [sqlite3_busy_timeout()] to name but three) that are methods on an
244
** sqlite3 object.
245
*/
246
typedef struct sqlite3 sqlite3;
247
248
/*
249
** CAPI3REF: 64-Bit Integer Types
250
** KEYWORDS: sqlite_int64 sqlite_uint64
251
**
252
** Because there is no cross-platform way to specify 64-bit integer types
253
** SQLite includes typedefs for 64-bit signed and unsigned integers.
254
**
255
** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
256
** The sqlite_int64 and sqlite_uint64 types are supported for backwards
257
** compatibility only.
258
**
259
** ^The sqlite3_int64 and sqlite_int64 types can store integer values
260
** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
261
** sqlite3_uint64 and sqlite_uint64 types can store integer values 
262
** between 0 and +18446744073709551615 inclusive.
263
*/
264
#ifdef SQLITE_INT64_TYPE
265
  typedef SQLITE_INT64_TYPE sqlite_int64;
266
# ifdef SQLITE_UINT64_TYPE
267
    typedef SQLITE_UINT64_TYPE sqlite_uint64;
268
# else  
269
    typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
270
# endif
271
#elif defined(_MSC_VER) || defined(__BORLANDC__)
272
  typedef __int64 sqlite_int64;
273
  typedef unsigned __int64 sqlite_uint64;
274
#else
275
  typedef long long int sqlite_int64;
276
  typedef unsigned long long int sqlite_uint64;
277
#endif
278
typedef sqlite_int64 sqlite3_int64;
279
typedef sqlite_uint64 sqlite3_uint64;
280
281
/*
282
** If compiling for a processor that lacks floating point support,
283
** substitute integer for floating-point.
284
*/
285
#ifdef SQLITE_OMIT_FLOATING_POINT
286
# define double sqlite3_int64
287
#endif
288
289
/*
290
** CAPI3REF: Closing A Database Connection
291
** DESTRUCTOR: sqlite3
292
**
293
** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
294
** for the [sqlite3] object.
295
** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
296
** the [sqlite3] object is successfully destroyed and all associated
297
** resources are deallocated.
298
**
299
** ^If the database connection is associated with unfinalized prepared
300
** statements or unfinished sqlite3_backup objects then sqlite3_close()
301
** will leave the database connection open and return [SQLITE_BUSY].
302
** ^If sqlite3_close_v2() is called with unfinalized prepared statements
303
** and/or unfinished sqlite3_backups, then the database connection becomes
304
** an unusable "zombie" which will automatically be deallocated when the
305
** last prepared statement is finalized or the last sqlite3_backup is
306
** finished.  The sqlite3_close_v2() interface is intended for use with
307
** host languages that are garbage collected, and where the order in which
308
** destructors are called is arbitrary.
309
**
310
** Applications should [sqlite3_finalize | finalize] all [prepared statements],
311
** [sqlite3_blob_close | close] all [BLOB handles], and 
312
** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
313
** with the [sqlite3] object prior to attempting to close the object.  ^If
314
** sqlite3_close_v2() is called on a [database connection] that still has
315
** outstanding [prepared statements], [BLOB handles], and/or
316
** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation
317
** of resources is deferred until all [prepared statements], [BLOB handles],
318
** and [sqlite3_backup] objects are also destroyed.
319
**
320
** ^If an [sqlite3] object is destroyed while a transaction is open,
321
** the transaction is automatically rolled back.
322
**
323
** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
324
** must be either a NULL
325
** pointer or an [sqlite3] object pointer obtained
326
** from [sqlite3_open()], [sqlite3_open16()], or
327
** [sqlite3_open_v2()], and not previously closed.
328
** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
329
** argument is a harmless no-op.
330
*/
331
SQLITE_API int sqlite3_close(sqlite3*);
332
SQLITE_API int sqlite3_close_v2(sqlite3*);
333
334
/*
335
** The type for a callback function.
336
** This is legacy and deprecated.  It is included for historical
337
** compatibility and is not documented.
338
*/
339
typedef int (*sqlite3_callback)(void*,int,char**, char**);
340
341
/*
342
** CAPI3REF: One-Step Query Execution Interface
343
** METHOD: sqlite3
344
**
345
** The sqlite3_exec() interface is a convenience wrapper around
346
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
347
** that allows an application to run multiple statements of SQL
348
** without having to use a lot of C code. 
349
**
350
** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
351
** semicolon-separate SQL statements passed into its 2nd argument,
352
** in the context of the [database connection] passed in as its 1st
353
** argument.  ^If the callback function of the 3rd argument to
354
** sqlite3_exec() is not NULL, then it is invoked for each result row
355
** coming out of the evaluated SQL statements.  ^The 4th argument to
356
** sqlite3_exec() is relayed through to the 1st argument of each
357
** callback invocation.  ^If the callback pointer to sqlite3_exec()
358
** is NULL, then no callback is ever invoked and result rows are
359
** ignored.
360
**
361
** ^If an error occurs while evaluating the SQL statements passed into
362
** sqlite3_exec(), then execution of the current statement stops and
363
** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
364
** is not NULL then any error message is written into memory obtained
365
** from [sqlite3_malloc()] and passed back through the 5th parameter.
366
** To avoid memory leaks, the application should invoke [sqlite3_free()]
367
** on error message strings returned through the 5th parameter of
368
** sqlite3_exec() after the error message string is no longer needed.
369
** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
370
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
371
** NULL before returning.
372
**
373
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
374
** routine returns SQLITE_ABORT without invoking the callback again and
375
** without running any subsequent SQL statements.
376
**
377
** ^The 2nd argument to the sqlite3_exec() callback function is the
378
** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
379
** callback is an array of pointers to strings obtained as if from
380
** [sqlite3_column_text()], one for each column.  ^If an element of a
381
** result row is NULL then the corresponding string pointer for the
382
** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
383
** sqlite3_exec() callback is an array of pointers to strings where each
384
** entry represents the name of corresponding result column as obtained
385
** from [sqlite3_column_name()].
386
**
387
** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
388
** to an empty string, or a pointer that contains only whitespace and/or 
389
** SQL comments, then no SQL statements are evaluated and the database
390
** is not changed.
391
**
392
** Restrictions:
393
**
394
** <ul>
395
** <li> The application must ensure that the 1st parameter to sqlite3_exec()
396
**      is a valid and open [database connection].
397
** <li> The application must not close the [database connection] specified by
398
**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
399
** <li> The application must not modify the SQL statement text passed into
400
**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
401
** </ul>
402
*/
403
SQLITE_API int sqlite3_exec(
404
  sqlite3*,                                  /* An open database */
405
  const char *sql,                           /* SQL to be evaluated */
406
  int (*callback)(void*,int,char**,char**),  /* Callback function */
407
  void *,                                    /* 1st argument to callback */
408
  char **errmsg                              /* Error msg written here */
409
);
410
411
/*
412
** CAPI3REF: Result Codes
413
** KEYWORDS: {result code definitions}
414
**
415
** Many SQLite functions return an integer result code from the set shown
416
** here in order to indicate success or failure.
417
**
418
** New error codes may be added in future versions of SQLite.
419
**
420
** See also: [extended result code definitions]
421
*/
422
15
#define SQLITE_OK           0   /* Successful result */
423
/* beginning-of-error-codes */
424
#define SQLITE_ERROR        1   /* Generic error */
425
#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
426
#define SQLITE_PERM         3   /* Access permission denied */
427
#define SQLITE_ABORT        4   /* Callback routine requested an abort */
428
#define SQLITE_BUSY         5   /* The database file is locked */
429
#define SQLITE_LOCKED       6   /* A table in the database is locked */
430
#define SQLITE_NOMEM        7   /* A malloc() failed */
431
#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
432
#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
433
#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
434
#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
435
#define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
436
#define SQLITE_FULL        13   /* Insertion failed because database is full */
437
#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
438
#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
439
#define SQLITE_EMPTY       16   /* Internal use only */
440
#define SQLITE_SCHEMA      17   /* The database schema changed */
441
#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
442
#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
443
#define SQLITE_MISMATCH    20   /* Data type mismatch */
444
#define SQLITE_MISUSE      21   /* Library used incorrectly */
445
#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
446
#define SQLITE_AUTH        23   /* Authorization denied */
447
#define SQLITE_FORMAT      24   /* Not used */
448
#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
449
#define SQLITE_NOTADB      26   /* File opened that is not a database file */
450
#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
451
#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
452
108
#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
453
#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
454
/* end-of-error-codes */
455
456
/*
457
** CAPI3REF: Extended Result Codes
458
** KEYWORDS: {extended result code definitions}
459
**
460
** In its default configuration, SQLite API routines return one of 30 integer
461
** [result codes].  However, experience has shown that many of
462
** these result codes are too coarse-grained.  They do not provide as
463
** much information about problems as programmers might like.  In an effort to
464
** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
465
** and later) include
466
** support for additional result codes that provide more detailed information
467
** about errors. These [extended result codes] are enabled or disabled
468
** on a per database connection basis using the
469
** [sqlite3_extended_result_codes()] API.  Or, the extended code for
470
** the most recent error can be obtained using
471
** [sqlite3_extended_errcode()].
472
*/
473
#define SQLITE_ERROR_MISSING_COLLSEQ   (SQLITE_ERROR | (1<<8))
474
#define SQLITE_ERROR_RETRY             (SQLITE_ERROR | (2<<8))
475
#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
476
#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
477
#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
478
#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
479
#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
480
#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
481
#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
482
#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
483
#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
484
#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
485
#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
486
#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
487
#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
488
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
489
#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
490
#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
491
#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
492
#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
493
#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
494
#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
495
#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
496
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
497
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
498
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
499
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
500
#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
501
#define SQLITE_IOERR_VNODE             (SQLITE_IOERR | (27<<8))
502
#define SQLITE_IOERR_AUTH              (SQLITE_IOERR | (28<<8))
503
#define SQLITE_IOERR_BEGIN_ATOMIC      (SQLITE_IOERR | (29<<8))
504
#define SQLITE_IOERR_COMMIT_ATOMIC     (SQLITE_IOERR | (30<<8))
505
#define SQLITE_IOERR_ROLLBACK_ATOMIC   (SQLITE_IOERR | (31<<8))
506
#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
507
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
508
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
509
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
510
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
511
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
512
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
513
#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
514
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
515
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
516
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
517
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
518
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
519
#define SQLITE_READONLY_DIRECTORY      (SQLITE_READONLY | (6<<8))
520
#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
521
#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
522
#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
523
#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
524
#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
525
#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
526
#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
527
#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
528
#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
529
#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
530
#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
531
#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
532
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
533
#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
534
#define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
535
#define SQLITE_OK_LOAD_PERMANENTLY     (SQLITE_OK | (1<<8))
536
537
/*
538
** CAPI3REF: Flags For File Open Operations
539
**
540
** These bit values are intended for use in the
541
** 3rd parameter to the [sqlite3_open_v2()] interface and
542
** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
543
*/
544
#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
545
#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
546
#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
547
#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
548
#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
549
#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
550
#define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
551
#define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
552
#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
553
#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
554
#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
555
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
556
#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
557
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
558
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
559
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
560
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
561
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
562
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
563
#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
564
565
/* Reserved:                         0x00F00000 */
566
567
/*
568
** CAPI3REF: Device Characteristics
569
**
570
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
571
** object returns an integer which is a vector of these
572
** bit values expressing I/O characteristics of the mass storage
573
** device that holds the file that the [sqlite3_io_methods]
574
** refers to.
575
**
576
** The SQLITE_IOCAP_ATOMIC property means that all writes of
577
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
578
** mean that writes of blocks that are nnn bytes in size and
579
** are aligned to an address which is an integer multiple of
580
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
581
** that when data is appended to a file, the data is appended
582
** first then the size of the file is extended, never the other
583
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
584
** information is written to disk in the same order as calls
585
** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
586
** after reboot following a crash or power loss, the only bytes in a
587
** file that were written at the application level might have changed
588
** and that adjacent bytes, even bytes within the same sector are
589
** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
590
** flag indicates that a file cannot be deleted when open.  The
591
** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
592
** read-only media and cannot be changed even by processes with
593
** elevated privileges.
594
**
595
** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
596
** filesystem supports doing multiple write operations atomically when those
597
** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
598
** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
599
*/
600
#define SQLITE_IOCAP_ATOMIC                 0x00000001
601
#define SQLITE_IOCAP_ATOMIC512              0x00000002
602
#define SQLITE_IOCAP_ATOMIC1K               0x00000004
603
#define SQLITE_IOCAP_ATOMIC2K               0x00000008
604
#define SQLITE_IOCAP_ATOMIC4K               0x00000010
605
#define SQLITE_IOCAP_ATOMIC8K               0x00000020
606
#define SQLITE_IOCAP_ATOMIC16K              0x00000040
607
#define SQLITE_IOCAP_ATOMIC32K              0x00000080
608
#define SQLITE_IOCAP_ATOMIC64K              0x00000100
609
#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
610
#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
611
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
612
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
613
#define SQLITE_IOCAP_IMMUTABLE              0x00002000
614
#define SQLITE_IOCAP_BATCH_ATOMIC           0x00004000
615
616
/*
617
** CAPI3REF: File Locking Levels
618
**
619
** SQLite uses one of these integer values as the second
620
** argument to calls it makes to the xLock() and xUnlock() methods
621
** of an [sqlite3_io_methods] object.
622
*/
623
#define SQLITE_LOCK_NONE          0
624
#define SQLITE_LOCK_SHARED        1
625
#define SQLITE_LOCK_RESERVED      2
626
#define SQLITE_LOCK_PENDING       3
627
#define SQLITE_LOCK_EXCLUSIVE     4
628
629
/*
630
** CAPI3REF: Synchronization Type Flags
631
**
632
** When SQLite invokes the xSync() method of an
633
** [sqlite3_io_methods] object it uses a combination of
634
** these integer values as the second argument.
635
**
636
** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
637
** sync operation only needs to flush data to mass storage.  Inode
638
** information need not be flushed. If the lower four bits of the flag
639
** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
640
** If the lower four bits equal SQLITE_SYNC_FULL, that means
641
** to use Mac OS X style fullsync instead of fsync().
642
**
643
** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
644
** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
645
** settings.  The [synchronous pragma] determines when calls to the
646
** xSync VFS method occur and applies uniformly across all platforms.
647
** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
648
** energetic or rigorous or forceful the sync operations are and
649
** only make a difference on Mac OSX for the default SQLite code.
650
** (Third-party VFS implementations might also make the distinction
651
** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
652
** operating systems natively supported by SQLite, only Mac OSX
653
** cares about the difference.)
654
*/
655
#define SQLITE_SYNC_NORMAL        0x00002
656
#define SQLITE_SYNC_FULL          0x00003
657
#define SQLITE_SYNC_DATAONLY      0x00010
658
659
/*
660
** CAPI3REF: OS Interface Open File Handle
661
**
662
** An [sqlite3_file] object represents an open file in the 
663
** [sqlite3_vfs | OS interface layer].  Individual OS interface
664
** implementations will
665
** want to subclass this object by appending additional fields
666
** for their own use.  The pMethods entry is a pointer to an
667
** [sqlite3_io_methods] object that defines methods for performing
668
** I/O operations on the open file.
669
*/
670
typedef struct sqlite3_file sqlite3_file;
671
struct sqlite3_file {
672
  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
673
};
674
675
/*
676
** CAPI3REF: OS Interface File Virtual Methods Object
677
**
678
** Every file opened by the [sqlite3_vfs.xOpen] method populates an
679
** [sqlite3_file] object (or, more commonly, a subclass of the
680
** [sqlite3_file] object) with a pointer to an instance of this object.
681
** This object defines the methods used to perform various operations
682
** against the open file represented by the [sqlite3_file] object.
683
**
684
** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 
685
** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
686
** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
687
** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
688
** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
689
** to NULL.
690
**
691
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
692
** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
693
** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
694
** flag may be ORed in to indicate that only the data of the file
695
** and not its inode needs to be synced.
696
**
697
** The integer values to xLock() and xUnlock() are one of
698
** <ul>
699
** <li> [SQLITE_LOCK_NONE],
700
** <li> [SQLITE_LOCK_SHARED],
701
** <li> [SQLITE_LOCK_RESERVED],
702
** <li> [SQLITE_LOCK_PENDING], or
703
** <li> [SQLITE_LOCK_EXCLUSIVE].
704
** </ul>
705
** xLock() increases the lock. xUnlock() decreases the lock.
706
** The xCheckReservedLock() method checks whether any database connection,
707
** either in this process or in some other process, is holding a RESERVED,
708
** PENDING, or EXCLUSIVE lock on the file.  It returns true
709
** if such a lock exists and false otherwise.
710
**
711
** The xFileControl() method is a generic interface that allows custom
712
** VFS implementations to directly control an open file using the
713
** [sqlite3_file_control()] interface.  The second "op" argument is an
714
** integer opcode.  The third argument is a generic pointer intended to
715
** point to a structure that may contain arguments or space in which to
716
** write return values.  Potential uses for xFileControl() might be
717
** functions to enable blocking locks with timeouts, to change the
718
** locking strategy (for example to use dot-file locks), to inquire
719
** about the status of a lock, or to break stale locks.  The SQLite
720
** core reserves all opcodes less than 100 for its own use.
721
** A [file control opcodes | list of opcodes] less than 100 is available.
722
** Applications that define a custom xFileControl method should use opcodes
723
** greater than 100 to avoid conflicts.  VFS implementations should
724
** return [SQLITE_NOTFOUND] for file control opcodes that they do not
725
** recognize.
726
**
727
** The xSectorSize() method returns the sector size of the
728
** device that underlies the file.  The sector size is the
729
** minimum write that can be performed without disturbing
730
** other bytes in the file.  The xDeviceCharacteristics()
731
** method returns a bit vector describing behaviors of the
732
** underlying device:
733
**
734
** <ul>
735
** <li> [SQLITE_IOCAP_ATOMIC]
736
** <li> [SQLITE_IOCAP_ATOMIC512]
737
** <li> [SQLITE_IOCAP_ATOMIC1K]
738
** <li> [SQLITE_IOCAP_ATOMIC2K]
739
** <li> [SQLITE_IOCAP_ATOMIC4K]
740
** <li> [SQLITE_IOCAP_ATOMIC8K]
741
** <li> [SQLITE_IOCAP_ATOMIC16K]
742
** <li> [SQLITE_IOCAP_ATOMIC32K]
743
** <li> [SQLITE_IOCAP_ATOMIC64K]
744
** <li> [SQLITE_IOCAP_SAFE_APPEND]
745
** <li> [SQLITE_IOCAP_SEQUENTIAL]
746
** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
747
** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
748
** <li> [SQLITE_IOCAP_IMMUTABLE]
749
** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
750
** </ul>
751
**
752
** The SQLITE_IOCAP_ATOMIC property means that all writes of
753
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
754
** mean that writes of blocks that are nnn bytes in size and
755
** are aligned to an address which is an integer multiple of
756
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
757
** that when data is appended to a file, the data is appended
758
** first then the size of the file is extended, never the other
759
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
760
** information is written to disk in the same order as calls
761
** to xWrite().
762
**
763
** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
764
** in the unread portions of the buffer with zeros.  A VFS that
765
** fails to zero-fill short reads might seem to work.  However,
766
** failure to zero-fill short reads will eventually lead to
767
** database corruption.
768
*/
769
typedef struct sqlite3_io_methods sqlite3_io_methods;
770
struct sqlite3_io_methods {
771
  int iVersion;
772
  int (*xClose)(sqlite3_file*);
773
  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
774
  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
775
  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
776
  int (*xSync)(sqlite3_file*, int flags);
777
  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
778
  int (*xLock)(sqlite3_file*, int);
779
  int (*xUnlock)(sqlite3_file*, int);
780
  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
781
  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
782
  int (*xSectorSize)(sqlite3_file*);
783
  int (*xDeviceCharacteristics)(sqlite3_file*);
784
  /* Methods above are valid for version 1 */
785
  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
786
  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
787
  void (*xShmBarrier)(sqlite3_file*);
788
  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
789
  /* Methods above are valid for version 2 */
790
  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
791
  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
792
  /* Methods above are valid for version 3 */
793
  /* Additional methods may be added in future releases */
794
};
795
796
/*
797
** CAPI3REF: Standard File Control Opcodes
798
** KEYWORDS: {file control opcodes} {file control opcode}
799
**
800
** These integer constants are opcodes for the xFileControl method
801
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
802
** interface.
803
**
804
** <ul>
805
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
806
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
807
** opcode causes the xFileControl method to write the current state of
808
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
809
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
810
** into an integer that the pArg argument points to. This capability
811
** is used during testing and is only available when the SQLITE_TEST
812
** compile-time option is used.
813
**
814
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
815
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
816
** layer a hint of how large the database file will grow to be during the
817
** current transaction.  This hint is not guaranteed to be accurate but it
818
** is often close.  The underlying VFS might choose to preallocate database
819
** file space based on this hint in order to help writes to the database
820
** file run faster.
821
**
822
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
823
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
824
** extends and truncates the database file in chunks of a size specified
825
** by the user. The fourth argument to [sqlite3_file_control()] should 
826
** point to an integer (type int) containing the new chunk-size to use
827
** for the nominated database. Allocating database file space in large
828
** chunks (say 1MB at a time), may reduce file-system fragmentation and
829
** improve performance on some systems.
830
**
831
** <li>[[SQLITE_FCNTL_FILE_POINTER]]
832
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
833
** to the [sqlite3_file] object associated with a particular database
834
** connection.  See also [SQLITE_FCNTL_JOURNAL_POINTER].
835
**
836
** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
837
** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
838
** to the [sqlite3_file] object associated with the journal file (either
839
** the [rollback journal] or the [write-ahead log]) for a particular database
840
** connection.  See also [SQLITE_FCNTL_FILE_POINTER].
841
**
842
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
843
** No longer in use.
844
**
845
** <li>[[SQLITE_FCNTL_SYNC]]
846
** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
847
** sent to the VFS immediately before the xSync method is invoked on a
848
** database file descriptor. Or, if the xSync method is not invoked 
849
** because the user has configured SQLite with 
850
** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 
851
** of the xSync method. In most cases, the pointer argument passed with
852
** this file-control is NULL. However, if the database file is being synced
853
** as part of a multi-database commit, the argument points to a nul-terminated
854
** string containing the transactions master-journal file name. VFSes that 
855
** do not need this signal should silently ignore this opcode. Applications 
856
** should not call [sqlite3_file_control()] with this opcode as doing so may 
857
** disrupt the operation of the specialized VFSes that do require it.  
858
**
859
** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
860
** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
861
** and sent to the VFS after a transaction has been committed immediately
862
** but before the database is unlocked. VFSes that do not need this signal
863
** should silently ignore this opcode. Applications should not call
864
** [sqlite3_file_control()] with this opcode as doing so may disrupt the 
865
** operation of the specialized VFSes that do require it.  
866
**
867
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
868
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
869
** retry counts and intervals for certain disk I/O operations for the
870
** windows [VFS] in order to provide robustness in the presence of
871
** anti-virus programs.  By default, the windows VFS will retry file read,
872
** file write, and file delete operations up to 10 times, with a delay
873
** of 25 milliseconds before the first retry and with the delay increasing
874
** by an additional 25 milliseconds with each subsequent retry.  This
875
** opcode allows these two values (10 retries and 25 milliseconds of delay)
876
** to be adjusted.  The values are changed for all database connections
877
** within the same process.  The argument is a pointer to an array of two
878
** integers where the first integer is the new retry count and the second
879
** integer is the delay.  If either integer is negative, then the setting
880
** is not changed but instead the prior value of that setting is written
881
** into the array entry, allowing the current retry settings to be
882
** interrogated.  The zDbName parameter is ignored.
883
**
884
** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
885
** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
886
** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
887
** write ahead log and shared memory files used for transaction control
888
** are automatically deleted when the latest connection to the database
889
** closes.  Setting persistent WAL mode causes those files to persist after
890
** close.  Persisting the files is useful when other processes that do not
891
** have write permission on the directory containing the database file want
892
** to read the database file, as the WAL and shared memory files must exist
893
** in order for the database to be readable.  The fourth parameter to
894
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
895
** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
896
** WAL mode.  If the integer is -1, then it is overwritten with the current
897
** WAL persistence setting.
898
**
899
** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
900
** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
901
** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
902
** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
903
** xDeviceCharacteristics methods. The fourth parameter to
904
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
905
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
906
** mode.  If the integer is -1, then it is overwritten with the current
907
** zero-damage mode setting.
908
**
909
** <li>[[SQLITE_FCNTL_OVERWRITE]]
910
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
911
** a write transaction to indicate that, unless it is rolled back for some
912
** reason, the entire database file will be overwritten by the current 
913
** transaction. This is used by VACUUM operations.
914
**
915
** <li>[[SQLITE_FCNTL_VFSNAME]]
916
** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
917
** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
918
** final bottom-level VFS are written into memory obtained from 
919
** [sqlite3_malloc()] and the result is stored in the char* variable
920
** that the fourth parameter of [sqlite3_file_control()] points to.
921
** The caller is responsible for freeing the memory when done.  As with
922
** all file-control actions, there is no guarantee that this will actually
923
** do anything.  Callers should initialize the char* variable to a NULL
924
** pointer in case this file-control is not implemented.  This file-control
925
** is intended for diagnostic use only.
926
**
927
** <li>[[SQLITE_FCNTL_VFS_POINTER]]
928
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
929
** [VFSes] currently in use.  ^(The argument X in
930
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
931
** of type "[sqlite3_vfs] **".  This opcodes will set *X
932
** to a pointer to the top-level VFS.)^
933
** ^When there are multiple VFS shims in the stack, this opcode finds the
934
** upper-most shim only.
935
**
936
** <li>[[SQLITE_FCNTL_PRAGMA]]
937
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 
938
** file control is sent to the open [sqlite3_file] object corresponding
939
** to the database file to which the pragma statement refers. ^The argument
940
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
941
** pointers to strings (char**) in which the second element of the array
942
** is the name of the pragma and the third element is the argument to the
943
** pragma or NULL if the pragma has no argument.  ^The handler for an
944
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
945
** of the char** argument point to a string obtained from [sqlite3_mprintf()]
946
** or the equivalent and that string will become the result of the pragma or
947
** the error message if the pragma fails. ^If the
948
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 
949
** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
950
** file control returns [SQLITE_OK], then the parser assumes that the
951
** VFS has handled the PRAGMA itself and the parser generates a no-op
952
** prepared statement if result string is NULL, or that returns a copy
953
** of the result string if the string is non-NULL.
954
** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
955
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
956
** that the VFS encountered an error while handling the [PRAGMA] and the
957
** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
958
** file control occurs at the beginning of pragma statement analysis and so
959
** it is able to override built-in [PRAGMA] statements.
960
**
961
** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
962
** ^The [SQLITE_FCNTL_BUSYHANDLER]
963
** file-control may be invoked by SQLite on the database file handle
964
** shortly after it is opened in order to provide a custom VFS with access
965
** to the connections busy-handler callback. The argument is of type (void **)
966
** - an array of two (void *) values. The first (void *) actually points
967
** to a function of type (int (*)(void *)). In order to invoke the connections
968
** busy-handler, this function should be invoked with the second (void *) in
969
** the array as the only argument. If it returns non-zero, then the operation
970
** should be retried. If it returns zero, the custom VFS should abandon the
971
** current operation.
972
**
973
** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
974
** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
975
** to have SQLite generate a
976
** temporary filename using the same algorithm that is followed to generate
977
** temporary filenames for TEMP tables and other internal uses.  The
978
** argument should be a char** which will be filled with the filename
979
** written into memory obtained from [sqlite3_malloc()].  The caller should
980
** invoke [sqlite3_free()] on the result to avoid a memory leak.
981
**
982
** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
983
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
984
** maximum number of bytes that will be used for memory-mapped I/O.
985
** The argument is a pointer to a value of type sqlite3_int64 that
986
** is an advisory maximum number of bytes in the file to memory map.  The
987
** pointer is overwritten with the old value.  The limit is not changed if
988
** the value originally pointed to is negative, and so the current limit 
989
** can be queried by passing in a pointer to a negative number.  This
990
** file-control is used internally to implement [PRAGMA mmap_size].
991
**
992
** <li>[[SQLITE_FCNTL_TRACE]]
993
** The [SQLITE_FCNTL_TRACE] file control provides advisory information
994
** to the VFS about what the higher layers of the SQLite stack are doing.
995
** This file control is used by some VFS activity tracing [shims].
996
** The argument is a zero-terminated string.  Higher layers in the
997
** SQLite stack may generate instances of this file control if
998
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
999
**
1000
** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1001
** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1002
** pointer to an integer and it writes a boolean into that integer depending
1003
** on whether or not the file has been renamed, moved, or deleted since it
1004
** was first opened.
1005
**
1006
** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
1007
** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
1008
** underlying native file handle associated with a file handle.  This file
1009
** control interprets its argument as a pointer to a native file handle and
1010
** writes the resulting value there.
1011
**
1012
** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1013
** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
1014
** opcode causes the xFileControl method to swap the file handle with the one
1015
** pointed to by the pArg argument.  This capability is used during testing
1016
** and only needs to be supported when SQLITE_TEST is defined.
1017
**
1018
** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1019
** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1020
** be advantageous to block on the next WAL lock if the lock is not immediately
1021
** available.  The WAL subsystem issues this signal during rare
1022
** circumstances in order to fix a problem with priority inversion.
1023
** Applications should <em>not</em> use this file-control.
1024
**
1025
** <li>[[SQLITE_FCNTL_ZIPVFS]]
1026
** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1027
** VFS should return SQLITE_NOTFOUND for this opcode.
1028
**
1029
** <li>[[SQLITE_FCNTL_RBU]]
1030
** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1031
** the RBU extension only.  All other VFS should return SQLITE_NOTFOUND for
1032
** this opcode.  
1033
**
1034
** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1035
** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1036
** the file descriptor is placed in "batch write mode", which
1037
** means all subsequent write operations will be deferred and done
1038
** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].  Systems
1039
** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1040
** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1041
** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1042
** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1043
** no VFS interface calls on the same [sqlite3_file] file descriptor
1044
** except for calls to the xWrite method and the xFileControl method
1045
** with [SQLITE_FCNTL_SIZE_HINT].
1046
**
1047
** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1048
** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1049
** operations since the previous successful call to 
1050
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1051
** This file control returns [SQLITE_OK] if and only if the writes were
1052
** all performed successfully and have been committed to persistent storage.
1053
** ^Regardless of whether or not it is successful, this file control takes
1054
** the file descriptor out of batch write mode so that all subsequent
1055
** write operations are independent.
1056
** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1057
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1058
**
1059
** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1060
** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1061
** operations since the previous successful call to 
1062
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1063
** ^This file control takes the file descriptor out of batch write mode
1064
** so that all subsequent write operations are independent.
1065
** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1066
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1067
**
1068
** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
1069
** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode causes attempts to obtain
1070
** a file lock using the xLock or xShmLock methods of the VFS to wait
1071
** for up to M milliseconds before failing, where M is the single 
1072
** unsigned integer parameter.
1073
** </ul>
1074
*/
1075
#define SQLITE_FCNTL_LOCKSTATE               1
1076
#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
1077
#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
1078
#define SQLITE_FCNTL_LAST_ERRNO              4
1079
#define SQLITE_FCNTL_SIZE_HINT               5
1080
#define SQLITE_FCNTL_CHUNK_SIZE              6
1081
#define SQLITE_FCNTL_FILE_POINTER            7
1082
#define SQLITE_FCNTL_SYNC_OMITTED            8
1083
#define SQLITE_FCNTL_WIN32_AV_RETRY          9
1084
#define SQLITE_FCNTL_PERSIST_WAL            10
1085
#define SQLITE_FCNTL_OVERWRITE              11
1086
#define SQLITE_FCNTL_VFSNAME                12
1087
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
1088
#define SQLITE_FCNTL_PRAGMA                 14
1089
#define SQLITE_FCNTL_BUSYHANDLER            15
1090
#define SQLITE_FCNTL_TEMPFILENAME           16
1091
#define SQLITE_FCNTL_MMAP_SIZE              18
1092
#define SQLITE_FCNTL_TRACE                  19
1093
#define SQLITE_FCNTL_HAS_MOVED              20
1094
#define SQLITE_FCNTL_SYNC                   21
1095
#define SQLITE_FCNTL_COMMIT_PHASETWO        22
1096
#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
1097
#define SQLITE_FCNTL_WAL_BLOCK              24
1098
#define SQLITE_FCNTL_ZIPVFS                 25
1099
#define SQLITE_FCNTL_RBU                    26
1100
#define SQLITE_FCNTL_VFS_POINTER            27
1101
#define SQLITE_FCNTL_JOURNAL_POINTER        28
1102
#define SQLITE_FCNTL_WIN32_GET_HANDLE       29
1103
#define SQLITE_FCNTL_PDB                    30
1104
#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE     31
1105
#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE    32
1106
#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE  33
1107
#define SQLITE_FCNTL_LOCK_TIMEOUT           34
1108
1109
/* deprecated names */
1110
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
1111
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
1112
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO
1113
1114
1115
/*
1116
** CAPI3REF: Mutex Handle
1117
**
1118
** The mutex module within SQLite defines [sqlite3_mutex] to be an
1119
** abstract type for a mutex object.  The SQLite core never looks
1120
** at the internal representation of an [sqlite3_mutex].  It only
1121
** deals with pointers to the [sqlite3_mutex] object.
1122
**
1123
** Mutexes are created using [sqlite3_mutex_alloc()].
1124
*/
1125
typedef struct sqlite3_mutex sqlite3_mutex;
1126
1127
/*
1128
** CAPI3REF: Loadable Extension Thunk
1129
**
1130
** A pointer to the opaque sqlite3_api_routines structure is passed as
1131
** the third parameter to entry points of [loadable extensions].  This
1132
** structure must be typedefed in order to work around compiler warnings
1133
** on some platforms.
1134
*/
1135
typedef struct sqlite3_api_routines sqlite3_api_routines;
1136
1137
/*
1138
** CAPI3REF: OS Interface Object
1139
**
1140
** An instance of the sqlite3_vfs object defines the interface between
1141
** the SQLite core and the underlying operating system.  The "vfs"
1142
** in the name of the object stands for "virtual file system".  See
1143
** the [VFS | VFS documentation] for further information.
1144
**
1145
** The VFS interface is sometimes extended by adding new methods onto
1146
** the end.  Each time such an extension occurs, the iVersion field
1147
** is incremented.  The iVersion value started out as 1 in
1148
** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
1149
** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
1150
** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6].  Additional fields
1151
** may be appended to the sqlite3_vfs object and the iVersion value
1152
** may increase again in future versions of SQLite.
1153
** Note that the structure
1154
** of the sqlite3_vfs object changes in the transition from
1155
** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
1156
** and yet the iVersion field was not modified.
1157
**
1158
** The szOsFile field is the size of the subclassed [sqlite3_file]
1159
** structure used by this VFS.  mxPathname is the maximum length of
1160
** a pathname in this VFS.
1161
**
1162
** Registered sqlite3_vfs objects are kept on a linked list formed by
1163
** the pNext pointer.  The [sqlite3_vfs_register()]
1164
** and [sqlite3_vfs_unregister()] interfaces manage this list
1165
** in a thread-safe way.  The [sqlite3_vfs_find()] interface
1166
** searches the list.  Neither the application code nor the VFS
1167
** implementation should use the pNext pointer.
1168
**
1169
** The pNext field is the only field in the sqlite3_vfs
1170
** structure that SQLite will ever modify.  SQLite will only access
1171
** or modify this field while holding a particular static mutex.
1172
** The application should never modify anything within the sqlite3_vfs
1173
** object once the object has been registered.
1174
**
1175
** The zName field holds the name of the VFS module.  The name must
1176
** be unique across all VFS modules.
1177
**
1178
** [[sqlite3_vfs.xOpen]]
1179
** ^SQLite guarantees that the zFilename parameter to xOpen
1180
** is either a NULL pointer or string obtained
1181
** from xFullPathname() with an optional suffix added.
1182
** ^If a suffix is added to the zFilename parameter, it will
1183
** consist of a single "-" character followed by no more than
1184
** 11 alphanumeric and/or "-" characters.
1185
** ^SQLite further guarantees that
1186
** the string will be valid and unchanged until xClose() is
1187
** called. Because of the previous sentence,
1188
** the [sqlite3_file] can safely store a pointer to the
1189
** filename if it needs to remember the filename for some reason.
1190
** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1191
** must invent its own temporary name for the file.  ^Whenever the 
1192
** xFilename parameter is NULL it will also be the case that the
1193
** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1194
**
1195
** The flags argument to xOpen() includes all bits set in
1196
** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
1197
** or [sqlite3_open16()] is used, then flags includes at least
1198
** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 
1199
** If xOpen() opens a file read-only then it sets *pOutFlags to
1200
** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
1201
**
1202
** ^(SQLite will also add one of the following flags to the xOpen()
1203
** call, depending on the object being opened:
1204
**
1205
** <ul>
1206
** <li>  [SQLITE_OPEN_MAIN_DB]
1207
** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
1208
** <li>  [SQLITE_OPEN_TEMP_DB]
1209
** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
1210
** <li>  [SQLITE_OPEN_TRANSIENT_DB]
1211
** <li>  [SQLITE_OPEN_SUBJOURNAL]
1212
** <li>  [SQLITE_OPEN_MASTER_JOURNAL]
1213
** <li>  [SQLITE_OPEN_WAL]
1214
** </ul>)^
1215
**
1216
** The file I/O implementation can use the object type flags to
1217
** change the way it deals with files.  For example, an application
1218
** that does not care about crash recovery or rollback might make
1219
** the open of a journal file a no-op.  Writes to this journal would
1220
** also be no-ops, and any attempt to read the journal would return
1221
** SQLITE_IOERR.  Or the implementation might recognize that a database
1222
** file will be doing page-aligned sector reads and writes in a random
1223
** order and set up its I/O subsystem accordingly.
1224
**
1225
** SQLite might also add one of the following flags to the xOpen method:
1226
**
1227
** <ul>
1228
** <li> [SQLITE_OPEN_DELETEONCLOSE]
1229
** <li> [SQLITE_OPEN_EXCLUSIVE]
1230
** </ul>
1231
**
1232
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1233
** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
1234
** will be set for TEMP databases and their journals, transient
1235
** databases, and subjournals.
1236
**
1237
** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1238
** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1239
** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1240
** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 
1241
** SQLITE_OPEN_CREATE, is used to indicate that file should always
1242
** be created, and that it is an error if it already exists.
1243
** It is <i>not</i> used to indicate the file should be opened 
1244
** for exclusive access.
1245
**
1246
** ^At least szOsFile bytes of memory are allocated by SQLite
1247
** to hold the  [sqlite3_file] structure passed as the third
1248
** argument to xOpen.  The xOpen method does not have to
1249
** allocate the structure; it should just fill it in.  Note that
1250
** the xOpen method must set the sqlite3_file.pMethods to either
1251
** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
1252
** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
1253
** element will be valid after xOpen returns regardless of the success
1254
** or failure of the xOpen call.
1255
**
1256
** [[sqlite3_vfs.xAccess]]
1257
** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1258
** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1259
** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1260
** to test whether a file is at least readable.   The file can be a
1261
** directory.
1262
**
1263
** ^SQLite will always allocate at least mxPathname+1 bytes for the
1264
** output buffer xFullPathname.  The exact size of the output buffer
1265
** is also passed as a parameter to both  methods. If the output buffer
1266
** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1267
** handled as a fatal error by SQLite, vfs implementations should endeavor
1268
** to prevent this by setting mxPathname to a sufficiently large value.
1269
**
1270
** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1271
** interfaces are not strictly a part of the filesystem, but they are
1272
** included in the VFS structure for completeness.
1273
** The xRandomness() function attempts to return nBytes bytes
1274
** of good-quality randomness into zOut.  The return value is
1275
** the actual number of bytes of randomness obtained.
1276
** The xSleep() method causes the calling thread to sleep for at
1277
** least the number of microseconds given.  ^The xCurrentTime()
1278
** method returns a Julian Day Number for the current date and time as
1279
** a floating point value.
1280
** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1281
** Day Number multiplied by 86400000 (the number of milliseconds in 
1282
** a 24-hour day).  
1283
** ^SQLite will use the xCurrentTimeInt64() method to get the current
1284
** date and time if that method is available (if iVersion is 2 or 
1285
** greater and the function pointer is not NULL) and will fall back
1286
** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1287
**
1288
** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1289
** are not used by the SQLite core.  These optional interfaces are provided
1290
** by some VFSes to facilitate testing of the VFS code. By overriding 
1291
** system calls with functions under its control, a test program can
1292
** simulate faults and error conditions that would otherwise be difficult
1293
** or impossible to induce.  The set of system calls that can be overridden
1294
** varies from one VFS to another, and from one version of the same VFS to the
1295
** next.  Applications that use these interfaces must be prepared for any
1296
** or all of these interfaces to be NULL or for their behavior to change
1297
** from one release to the next.  Applications must not attempt to access
1298
** any of these methods if the iVersion of the VFS is less than 3.
1299
*/
1300
typedef struct sqlite3_vfs sqlite3_vfs;
1301
typedef void (*sqlite3_syscall_ptr)(void);
1302
struct sqlite3_vfs {
1303
  int iVersion;            /* Structure version number (currently 3) */
1304
  int szOsFile;            /* Size of subclassed sqlite3_file */
1305
  int mxPathname;          /* Maximum file pathname length */
1306
  sqlite3_vfs *pNext;      /* Next registered VFS */
1307
  const char *zName;       /* Name of this virtual file system */
1308
  void *pAppData;          /* Pointer to application-specific data */
1309
  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1310
               int flags, int *pOutFlags);
1311
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1312
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1313
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1314
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1315
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1316
  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1317
  void (*xDlClose)(sqlite3_vfs*, void*);
1318
  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1319
  int (*xSleep)(sqlite3_vfs*, int microseconds);
1320
  int (*xCurrentTime)(sqlite3_vfs*, double*);
1321
  int (*xGetLastError)(sqlite3_vfs*, int, char *);
1322
  /*
1323
  ** The methods above are in version 1 of the sqlite_vfs object
1324
  ** definition.  Those that follow are added in version 2 or later
1325
  */
1326
  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1327
  /*
1328
  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1329
  ** Those below are for version 3 and greater.
1330
  */
1331
  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1332
  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1333
  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1334
  /*
1335
  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1336
  ** New fields may be appended in future versions.  The iVersion
1337
  ** value will increment whenever this happens. 
1338
  */
1339
};
1340
1341
/*
1342
** CAPI3REF: Flags for the xAccess VFS method
1343
**
1344
** These integer constants can be used as the third parameter to
1345
** the xAccess method of an [sqlite3_vfs] object.  They determine
1346
** what kind of permissions the xAccess method is looking for.
1347
** With SQLITE_ACCESS_EXISTS, the xAccess method
1348
** simply checks whether the file exists.
1349
** With SQLITE_ACCESS_READWRITE, the xAccess method
1350
** checks whether the named directory is both readable and writable
1351
** (in other words, if files can be added, removed, and renamed within
1352
** the directory).
1353
** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1354
** [temp_store_directory pragma], though this could change in a future
1355
** release of SQLite.
1356
** With SQLITE_ACCESS_READ, the xAccess method
1357
** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
1358
** currently unused, though it might be used in a future release of
1359
** SQLite.
1360
*/
1361
#define SQLITE_ACCESS_EXISTS    0
1362
#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
1363
#define SQLITE_ACCESS_READ      2   /* Unused */
1364
1365
/*
1366
** CAPI3REF: Flags for the xShmLock VFS method
1367
**
1368
** These integer constants define the various locking operations
1369
** allowed by the xShmLock method of [sqlite3_io_methods].  The
1370
** following are the only legal combinations of flags to the
1371
** xShmLock method:
1372
**
1373
** <ul>
1374
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1375
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1376
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1377
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1378
** </ul>
1379
**
1380
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1381
** was given on the corresponding lock.  
1382
**
1383
** The xShmLock method can transition between unlocked and SHARED or
1384
** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
1385
** and EXCLUSIVE.
1386
*/
1387
#define SQLITE_SHM_UNLOCK       1
1388
#define SQLITE_SHM_LOCK         2
1389
#define SQLITE_SHM_SHARED       4
1390
#define SQLITE_SHM_EXCLUSIVE    8
1391
1392
/*
1393
** CAPI3REF: Maximum xShmLock index
1394
**
1395
** The xShmLock method on [sqlite3_io_methods] may use values
1396
** between 0 and this upper bound as its "offset" argument.
1397
** The SQLite core will never attempt to acquire or release a
1398
** lock outside of this range
1399
*/
1400
#define SQLITE_SHM_NLOCK        8
1401
1402
1403
/*
1404
** CAPI3REF: Initialize The SQLite Library
1405
**
1406
** ^The sqlite3_initialize() routine initializes the
1407
** SQLite library.  ^The sqlite3_shutdown() routine
1408
** deallocates any resources that were allocated by sqlite3_initialize().
1409
** These routines are designed to aid in process initialization and
1410
** shutdown on embedded systems.  Workstation applications using
1411
** SQLite normally do not need to invoke either of these routines.
1412
**
1413
** A call to sqlite3_initialize() is an "effective" call if it is
1414
** the first time sqlite3_initialize() is invoked during the lifetime of
1415
** the process, or if it is the first time sqlite3_initialize() is invoked
1416
** following a call to sqlite3_shutdown().  ^(Only an effective call
1417
** of sqlite3_initialize() does any initialization.  All other calls
1418
** are harmless no-ops.)^
1419
**
1420
** A call to sqlite3_shutdown() is an "effective" call if it is the first
1421
** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
1422
** an effective call to sqlite3_shutdown() does any deinitialization.
1423
** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1424
**
1425
** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1426
** is not.  The sqlite3_shutdown() interface must only be called from a
1427
** single thread.  All open [database connections] must be closed and all
1428
** other SQLite resources must be deallocated prior to invoking
1429
** sqlite3_shutdown().
1430
**
1431
** Among other things, ^sqlite3_initialize() will invoke
1432
** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
1433
** will invoke sqlite3_os_end().
1434
**
1435
** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1436
** ^If for some reason, sqlite3_initialize() is unable to initialize
1437
** the library (perhaps it is unable to allocate a needed resource such
1438
** as a mutex) it returns an [error code] other than [SQLITE_OK].
1439
**
1440
** ^The sqlite3_initialize() routine is called internally by many other
1441
** SQLite interfaces so that an application usually does not need to
1442
** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
1443
** calls sqlite3_initialize() so the SQLite library will be automatically
1444
** initialized when [sqlite3_open()] is called if it has not be initialized
1445
** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1446
** compile-time option, then the automatic calls to sqlite3_initialize()
1447
** are omitted and the application must call sqlite3_initialize() directly
1448
** prior to using any other SQLite interface.  For maximum portability,
1449
** it is recommended that applications always invoke sqlite3_initialize()
1450
** directly prior to using any other SQLite interface.  Future releases
1451
** of SQLite may require this.  In other words, the behavior exhibited
1452
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1453
** default behavior in some future release of SQLite.
1454
**
1455
** The sqlite3_os_init() routine does operating-system specific
1456
** initialization of the SQLite library.  The sqlite3_os_end()
1457
** routine undoes the effect of sqlite3_os_init().  Typical tasks
1458
** performed by these routines include allocation or deallocation
1459
** of static resources, initialization of global variables,
1460
** setting up a default [sqlite3_vfs] module, or setting up
1461
** a default configuration using [sqlite3_config()].
1462
**
1463
** The application should never invoke either sqlite3_os_init()
1464
** or sqlite3_os_end() directly.  The application should only invoke
1465
** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
1466
** interface is called automatically by sqlite3_initialize() and
1467
** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
1468
** implementations for sqlite3_os_init() and sqlite3_os_end()
1469
** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1470
** When [custom builds | built for other platforms]
1471
** (using the [SQLITE_OS_OTHER=1] compile-time
1472
** option) the application must supply a suitable implementation for
1473
** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
1474
** implementation of sqlite3_os_init() or sqlite3_os_end()
1475
** must return [SQLITE_OK] on success and some other [error code] upon
1476
** failure.
1477
*/
1478
SQLITE_API int sqlite3_initialize(void);
1479
SQLITE_API int sqlite3_shutdown(void);
1480
SQLITE_API int sqlite3_os_init(void);
1481
SQLITE_API int sqlite3_os_end(void);
1482
1483
/*
1484
** CAPI3REF: Configuring The SQLite Library
1485
**
1486
** The sqlite3_config() interface is used to make global configuration
1487
** changes to SQLite in order to tune SQLite to the specific needs of
1488
** the application.  The default configuration is recommended for most
1489
** applications and so this routine is usually not necessary.  It is
1490
** provided to support rare applications with unusual needs.
1491
**
1492
** <b>The sqlite3_config() interface is not threadsafe. The application
1493
** must ensure that no other SQLite interfaces are invoked by other
1494
** threads while sqlite3_config() is running.</b>
1495
**
1496
** The sqlite3_config() interface
1497
** may only be invoked prior to library initialization using
1498
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1499
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1500
** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1501
** Note, however, that ^sqlite3_config() can be called as part of the
1502
** implementation of an application-defined [sqlite3_os_init()].
1503
**
1504
** The first argument to sqlite3_config() is an integer
1505
** [configuration option] that determines
1506
** what property of SQLite is to be configured.  Subsequent arguments
1507
** vary depending on the [configuration option]
1508
** in the first argument.
1509
**
1510
** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1511
** ^If the option is unknown or SQLite is unable to set the option
1512
** then this routine returns a non-zero [error code].
1513
*/
1514
SQLITE_API int sqlite3_config(int, ...);
1515
1516
/*
1517
** CAPI3REF: Configure database connections
1518
** METHOD: sqlite3
1519
**
1520
** The sqlite3_db_config() interface is used to make configuration
1521
** changes to a [database connection].  The interface is similar to
1522
** [sqlite3_config()] except that the changes apply to a single
1523
** [database connection] (specified in the first argument).
1524
**
1525
** The second argument to sqlite3_db_config(D,V,...)  is the
1526
** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 
1527
** that indicates what aspect of the [database connection] is being configured.
1528
** Subsequent arguments vary depending on the configuration verb.
1529
**
1530
** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1531
** the call is considered successful.
1532
*/
1533
SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1534
1535
/*
1536
** CAPI3REF: Memory Allocation Routines
1537
**
1538
** An instance of this object defines the interface between SQLite
1539
** and low-level memory allocation routines.
1540
**
1541
** This object is used in only one place in the SQLite interface.
1542
** A pointer to an instance of this object is the argument to
1543
** [sqlite3_config()] when the configuration option is
1544
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].  
1545
** By creating an instance of this object
1546
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1547
** during configuration, an application can specify an alternative
1548
** memory allocation subsystem for SQLite to use for all of its
1549
** dynamic memory needs.
1550
**
1551
** Note that SQLite comes with several [built-in memory allocators]
1552
** that are perfectly adequate for the overwhelming majority of applications
1553
** and that this object is only useful to a tiny minority of applications
1554
** with specialized memory allocation requirements.  This object is
1555
** also used during testing of SQLite in order to specify an alternative
1556
** memory allocator that simulates memory out-of-memory conditions in
1557
** order to verify that SQLite recovers gracefully from such
1558
** conditions.
1559
**
1560
** The xMalloc, xRealloc, and xFree methods must work like the
1561
** malloc(), realloc() and free() functions from the standard C library.
1562
** ^SQLite guarantees that the second argument to
1563
** xRealloc is always a value returned by a prior call to xRoundup.
1564
**
1565
** xSize should return the allocated size of a memory allocation
1566
** previously obtained from xMalloc or xRealloc.  The allocated size
1567
** is always at least as big as the requested size but may be larger.
1568
**
1569
** The xRoundup method returns what would be the allocated size of
1570
** a memory allocation given a particular requested size.  Most memory
1571
** allocators round up memory allocations at least to the next multiple
1572
** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1573
** Every memory allocation request coming in through [sqlite3_malloc()]
1574
** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0, 
1575
** that causes the corresponding memory allocation to fail.
1576
**
1577
** The xInit method initializes the memory allocator.  For example,
1578
** it might allocate any require mutexes or initialize internal data
1579
** structures.  The xShutdown method is invoked (indirectly) by
1580
** [sqlite3_shutdown()] and should deallocate any resources acquired
1581
** by xInit.  The pAppData pointer is used as the only parameter to
1582
** xInit and xShutdown.
1583
**
1584
** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1585
** the xInit method, so the xInit method need not be threadsafe.  The
1586
** xShutdown method is only called from [sqlite3_shutdown()] so it does
1587
** not need to be threadsafe either.  For all other methods, SQLite
1588
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1589
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1590
** it is by default) and so the methods are automatically serialized.
1591
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1592
** methods must be threadsafe or else make their own arrangements for
1593
** serialization.
1594
**
1595
** SQLite will never invoke xInit() more than once without an intervening
1596
** call to xShutdown().
1597
*/
1598
typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1599
struct sqlite3_mem_methods {
1600
  void *(*xMalloc)(int);         /* Memory allocation function */
1601
  void (*xFree)(void*);          /* Free a prior allocation */
1602
  void *(*xRealloc)(void*,int);  /* Resize an allocation */
1603
  int (*xSize)(void*);           /* Return the size of an allocation */
1604
  int (*xRoundup)(int);          /* Round up request size to allocation size */
1605
  int (*xInit)(void*);           /* Initialize the memory allocator */
1606
  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
1607
  void *pAppData;                /* Argument to xInit() and xShutdown() */
1608
};
1609
1610
/*
1611
** CAPI3REF: Configuration Options
1612
** KEYWORDS: {configuration option}
1613
**
1614
** These constants are the available integer configuration options that
1615
** can be passed as the first argument to the [sqlite3_config()] interface.
1616
**
1617
** New configuration options may be added in future releases of SQLite.
1618
** Existing configuration options might be discontinued.  Applications
1619
** should check the return code from [sqlite3_config()] to make sure that
1620
** the call worked.  The [sqlite3_config()] interface will return a
1621
** non-zero [error code] if a discontinued or unsupported configuration option
1622
** is invoked.
1623
**
1624
** <dl>
1625
** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1626
** <dd>There are no arguments to this option.  ^This option sets the
1627
** [threading mode] to Single-thread.  In other words, it disables
1628
** all mutexing and puts SQLite into a mode where it can only be used
1629
** by a single thread.   ^If SQLite is compiled with
1630
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1631
** it is not possible to change the [threading mode] from its default
1632
** value of Single-thread and so [sqlite3_config()] will return 
1633
** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1634
** configuration option.</dd>
1635
**
1636
** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1637
** <dd>There are no arguments to this option.  ^This option sets the
1638
** [threading mode] to Multi-thread.  In other words, it disables
1639
** mutexing on [database connection] and [prepared statement] objects.
1640
** The application is responsible for serializing access to
1641
** [database connections] and [prepared statements].  But other mutexes
1642
** are enabled so that SQLite will be safe to use in a multi-threaded
1643
** environment as long as no two threads attempt to use the same
1644
** [database connection] at the same time.  ^If SQLite is compiled with
1645
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1646
** it is not possible to set the Multi-thread [threading mode] and
1647
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1648
** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1649
**
1650
** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1651
** <dd>There are no arguments to this option.  ^This option sets the
1652
** [threading mode] to Serialized. In other words, this option enables
1653
** all mutexes including the recursive
1654
** mutexes on [database connection] and [prepared statement] objects.
1655
** In this mode (which is the default when SQLite is compiled with
1656
** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1657
** to [database connections] and [prepared statements] so that the
1658
** application is free to use the same [database connection] or the
1659
** same [prepared statement] in different threads at the same time.
1660
** ^If SQLite is compiled with
1661
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1662
** it is not possible to set the Serialized [threading mode] and
1663
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1664
** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1665
**
1666
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1667
** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 
1668
** a pointer to an instance of the [sqlite3_mem_methods] structure.
1669
** The argument specifies
1670
** alternative low-level memory allocation routines to be used in place of
1671
** the memory allocation routines built into SQLite.)^ ^SQLite makes
1672
** its own private copy of the content of the [sqlite3_mem_methods] structure
1673
** before the [sqlite3_config()] call returns.</dd>
1674
**
1675
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1676
** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1677
** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1678
** The [sqlite3_mem_methods]
1679
** structure is filled with the currently defined memory allocation routines.)^
1680
** This option can be used to overload the default memory allocation
1681
** routines with a wrapper that simulations memory allocation failure or
1682
** tracks memory usage, for example. </dd>
1683
**
1684
** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
1685
** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
1686
** type int, interpreted as a boolean, which if true provides a hint to
1687
** SQLite that it should avoid large memory allocations if possible.
1688
** SQLite will run faster if it is free to make large memory allocations,
1689
** but some application might prefer to run slower in exchange for
1690
** guarantees about memory fragmentation that are possible if large
1691
** allocations are avoided.  This hint is normally off.
1692
** </dd>
1693
**
1694
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1695
** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1696
** interpreted as a boolean, which enables or disables the collection of
1697
** memory allocation statistics. ^(When memory allocation statistics are
1698
** disabled, the following SQLite interfaces become non-operational:
1699
**   <ul>
1700
**   <li> [sqlite3_memory_used()]
1701
**   <li> [sqlite3_memory_highwater()]
1702
**   <li> [sqlite3_soft_heap_limit64()]
1703
**   <li> [sqlite3_status64()]
1704
**   </ul>)^
1705
** ^Memory allocation statistics are enabled by default unless SQLite is
1706
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1707
** allocation statistics are disabled by default.
1708
** </dd>
1709
**
1710
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1711
** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1712
** </dd>
1713
**
1714
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1715
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1716
** that SQLite can use for the database page cache with the default page
1717
** cache implementation.  
1718
** This configuration option is a no-op if an application-define page
1719
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1720
** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1721
** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1722
** and the number of cache lines (N).
1723
** The sz argument should be the size of the largest database page
1724
** (a power of two between 512 and 65536) plus some extra bytes for each
1725
** page header.  ^The number of extra bytes needed by the page header
1726
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1727
** ^It is harmless, apart from the wasted memory,
1728
** for the sz parameter to be larger than necessary.  The pMem
1729
** argument must be either a NULL pointer or a pointer to an 8-byte
1730
** aligned block of memory of at least sz*N bytes, otherwise
1731
** subsequent behavior is undefined.
1732
** ^When pMem is not NULL, SQLite will strive to use the memory provided
1733
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1734
** a page cache line is larger than sz bytes or if all of the pMem buffer
1735
** is exhausted.
1736
** ^If pMem is NULL and N is non-zero, then each database connection
1737
** does an initial bulk allocation for page cache memory
1738
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1739
** of -1024*N bytes if N is negative, . ^If additional
1740
** page cache memory is needed beyond what is provided by the initial
1741
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1742
** additional cache line. </dd>
1743
**
1744
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1745
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 
1746
** that SQLite will use for all of its dynamic memory allocation needs
1747
** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1748
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1749
** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1750
** [SQLITE_ERROR] if invoked otherwise.
1751
** ^There are three arguments to SQLITE_CONFIG_HEAP:
1752
** An 8-byte aligned pointer to the memory,
1753
** the number of bytes in the memory buffer, and the minimum allocation size.
1754
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1755
** to using its default memory allocator (the system malloc() implementation),
1756
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
1757
** memory pointer is not NULL then the alternative memory
1758
** allocator is engaged to handle all of SQLites memory allocation needs.
1759
** The first pointer (the memory pointer) must be aligned to an 8-byte
1760
** boundary or subsequent behavior of SQLite will be undefined.
1761
** The minimum allocation size is capped at 2**12. Reasonable values
1762
** for the minimum allocation size are 2**5 through 2**8.</dd>
1763
**
1764
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1765
** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1766
** pointer to an instance of the [sqlite3_mutex_methods] structure.
1767
** The argument specifies alternative low-level mutex routines to be used
1768
** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
1769
** the content of the [sqlite3_mutex_methods] structure before the call to
1770
** [sqlite3_config()] returns. ^If SQLite is compiled with
1771
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1772
** the entire mutexing subsystem is omitted from the build and hence calls to
1773
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1774
** return [SQLITE_ERROR].</dd>
1775
**
1776
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1777
** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1778
** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
1779
** [sqlite3_mutex_methods]
1780
** structure is filled with the currently defined mutex routines.)^
1781
** This option can be used to overload the default mutex allocation
1782
** routines with a wrapper used to track mutex usage for performance
1783
** profiling or testing, for example.   ^If SQLite is compiled with
1784
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1785
** the entire mutexing subsystem is omitted from the build and hence calls to
1786
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1787
** return [SQLITE_ERROR].</dd>
1788
**
1789
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1790
** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1791
** the default size of lookaside memory on each [database connection].
1792
** The first argument is the
1793
** size of each lookaside buffer slot and the second is the number of
1794
** slots allocated to each database connection.)^  ^(SQLITE_CONFIG_LOOKASIDE
1795
** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1796
** option to [sqlite3_db_config()] can be used to change the lookaside
1797
** configuration on individual connections.)^ </dd>
1798
**
1799
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1800
** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 
1801
** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
1802
** the interface to a custom page cache implementation.)^
1803
** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1804
**
1805
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1806
** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
1807
** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
1808
** the current page cache implementation into that object.)^ </dd>
1809
**
1810
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1811
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1812
** global [error log].
1813
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1814
** function with a call signature of void(*)(void*,int,const char*), 
1815
** and a pointer to void. ^If the function pointer is not NULL, it is
1816
** invoked by [sqlite3_log()] to process each logging event.  ^If the
1817
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1818
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1819
** passed through as the first parameter to the application-defined logger
1820
** function whenever that function is invoked.  ^The second parameter to
1821
** the logger function is a copy of the first parameter to the corresponding
1822
** [sqlite3_log()] call and is intended to be a [result code] or an
1823
** [extended result code].  ^The third parameter passed to the logger is
1824
** log message after formatting via [sqlite3_snprintf()].
1825
** The SQLite logging interface is not reentrant; the logger function
1826
** supplied by the application must not invoke any SQLite interface.
1827
** In a multi-threaded application, the application-defined logger
1828
** function must be threadsafe. </dd>
1829
**
1830
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1831
** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
1832
** If non-zero, then URI handling is globally enabled. If the parameter is zero,
1833
** then URI handling is globally disabled.)^ ^If URI handling is globally
1834
** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
1835
** [sqlite3_open16()] or
1836
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1837
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1838
** connection is opened. ^If it is globally disabled, filenames are
1839
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1840
** database connection is opened. ^(By default, URI handling is globally
1841
** disabled. The default value may be changed by compiling with the
1842
** [SQLITE_USE_URI] symbol defined.)^
1843
**
1844
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1845
** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
1846
** argument which is interpreted as a boolean in order to enable or disable
1847
** the use of covering indices for full table scans in the query optimizer.
1848
** ^The default setting is determined
1849
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1850
** if that compile-time option is omitted.
1851
** The ability to disable the use of covering indices for full table scans
1852
** is because some incorrectly coded legacy applications might malfunction
1853
** when the optimization is enabled.  Providing the ability to
1854
** disable the optimization allows the older, buggy application code to work
1855
** without change even with newer versions of SQLite.
1856
**
1857
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1858
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1859
** <dd> These options are obsolete and should not be used by new code.
1860
** They are retained for backwards compatibility but are now no-ops.
1861
** </dd>
1862
**
1863
** [[SQLITE_CONFIG_SQLLOG]]
1864
** <dt>SQLITE_CONFIG_SQLLOG
1865
** <dd>This option is only available if sqlite is compiled with the
1866
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1867
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1868
** The second should be of type (void*). The callback is invoked by the library
1869
** in three separate circumstances, identified by the value passed as the
1870
** fourth parameter. If the fourth parameter is 0, then the database connection
1871
** passed as the second argument has just been opened. The third argument
1872
** points to a buffer containing the name of the main database file. If the
1873
** fourth parameter is 1, then the SQL statement that the third parameter
1874
** points to has just been executed. Or, if the fourth parameter is 2, then
1875
** the connection being passed as the second parameter is being closed. The
1876
** third parameter is passed NULL In this case.  An example of using this
1877
** configuration option can be seen in the "test_sqllog.c" source file in
1878
** the canonical SQLite source tree.</dd>
1879
**
1880
** [[SQLITE_CONFIG_MMAP_SIZE]]
1881
** <dt>SQLITE_CONFIG_MMAP_SIZE
1882
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
1883
** that are the default mmap size limit (the default setting for
1884
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
1885
** ^The default setting can be overridden by each database connection using
1886
** either the [PRAGMA mmap_size] command, or by using the
1887
** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
1888
** will be silently truncated if necessary so that it does not exceed the
1889
** compile-time maximum mmap size set by the
1890
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
1891
** ^If either argument to this option is negative, then that argument is
1892
** changed to its compile-time default.
1893
**
1894
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
1895
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
1896
** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
1897
** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
1898
** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
1899
** that specifies the maximum size of the created heap.
1900
**
1901
** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
1902
** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
1903
** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
1904
** is a pointer to an integer and writes into that integer the number of extra
1905
** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
1906
** The amount of extra space required can change depending on the compiler,
1907
** target platform, and SQLite version.
1908
**
1909
** [[SQLITE_CONFIG_PMASZ]]
1910
** <dt>SQLITE_CONFIG_PMASZ
1911
** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
1912
** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
1913
** sorter to that integer.  The default minimum PMA Size is set by the
1914
** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
1915
** to help with sort operations when multithreaded sorting
1916
** is enabled (using the [PRAGMA threads] command) and the amount of content
1917
** to be sorted exceeds the page size times the minimum of the
1918
** [PRAGMA cache_size] setting and this value.
1919
**
1920
** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
1921
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
1922
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
1923
** becomes the [statement journal] spill-to-disk threshold.  
1924
** [Statement journals] are held in memory until their size (in bytes)
1925
** exceeds this threshold, at which point they are written to disk.
1926
** Or if the threshold is -1, statement journals are always held
1927
** exclusively in memory.
1928
** Since many statement journals never become large, setting the spill
1929
** threshold to a value such as 64KiB can greatly reduce the amount of
1930
** I/O required to support statement rollback.
1931
** The default value for this setting is controlled by the
1932
** [SQLITE_STMTJRNL_SPILL] compile-time option.
1933
** </dl>
1934
*/
1935
#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
1936
#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
1937
#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
1938
#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
1939
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
1940
#define SQLITE_CONFIG_SCRATCH       6  /* No longer used */
1941
#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
1942
#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
1943
#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
1944
#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
1945
#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
1946
/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 
1947
#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
1948
#define SQLITE_CONFIG_PCACHE       14  /* no-op */
1949
#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
1950
#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
1951
#define SQLITE_CONFIG_URI          17  /* int */
1952
#define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
1953
#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
1954
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
1955
#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
1956
#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
1957
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
1958
#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
1959
#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
1960
#define SQLITE_CONFIG_STMTJRNL_SPILL      26  /* int nByte */
1961
#define SQLITE_CONFIG_SMALL_MALLOC        27  /* boolean */
1962
1963
/*
1964
** CAPI3REF: Database Connection Configuration Options
1965
**
1966
** These constants are the available integer configuration options that
1967
** can be passed as the second argument to the [sqlite3_db_config()] interface.
1968
**
1969
** New configuration options may be added in future releases of SQLite.
1970
** Existing configuration options might be discontinued.  Applications
1971
** should check the return code from [sqlite3_db_config()] to make sure that
1972
** the call worked.  ^The [sqlite3_db_config()] interface will return a
1973
** non-zero [error code] if a discontinued or unsupported configuration option
1974
** is invoked.
1975
**
1976
** <dl>
1977
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1978
** <dd> ^This option takes three additional arguments that determine the 
1979
** [lookaside memory allocator] configuration for the [database connection].
1980
** ^The first argument (the third parameter to [sqlite3_db_config()] is a
1981
** pointer to a memory buffer to use for lookaside memory.
1982
** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1983
** may be NULL in which case SQLite will allocate the
1984
** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1985
** size of each lookaside buffer slot.  ^The third argument is the number of
1986
** slots.  The size of the buffer in the first argument must be greater than
1987
** or equal to the product of the second and third arguments.  The buffer
1988
** must be aligned to an 8-byte boundary.  ^If the second argument to
1989
** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1990
** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
1991
** configuration for a database connection can only be changed when that
1992
** connection is not currently using lookaside memory, or in other words
1993
** when the "current value" returned by
1994
** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
1995
** Any attempt to change the lookaside memory configuration when lookaside
1996
** memory is in use leaves the configuration unchanged and returns 
1997
** [SQLITE_BUSY].)^</dd>
1998
**
1999
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2000
** <dd> ^This option is used to enable or disable the enforcement of
2001
** [foreign key constraints].  There should be two additional arguments.
2002
** The first argument is an integer which is 0 to disable FK enforcement,
2003
** positive to enable FK enforcement or negative to leave FK enforcement
2004
** unchanged.  The second parameter is a pointer to an integer into which
2005
** is written 0 or 1 to indicate whether FK enforcement is off or on
2006
** following this call.  The second parameter may be a NULL pointer, in
2007
** which case the FK enforcement setting is not reported back. </dd>
2008
**
2009
** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2010
** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2011
** There should be two additional arguments.
2012
** The first argument is an integer which is 0 to disable triggers,
2013
** positive to enable triggers or negative to leave the setting unchanged.
2014
** The second parameter is a pointer to an integer into which
2015
** is written 0 or 1 to indicate whether triggers are disabled or enabled
2016
** following this call.  The second parameter may be a NULL pointer, in
2017
** which case the trigger setting is not reported back. </dd>
2018
**
2019
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
2020
** <dd> ^This option is used to enable or disable the two-argument
2021
** version of the [fts3_tokenizer()] function which is part of the
2022
** [FTS3] full-text search engine extension.
2023
** There should be two additional arguments.
2024
** The first argument is an integer which is 0 to disable fts3_tokenizer() or
2025
** positive to enable fts3_tokenizer() or negative to leave the setting
2026
** unchanged.
2027
** The second parameter is a pointer to an integer into which
2028
** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
2029
** following this call.  The second parameter may be a NULL pointer, in
2030
** which case the new setting is not reported back. </dd>
2031
**
2032
** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2033
** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2034
** interface independently of the [load_extension()] SQL function.
2035
** The [sqlite3_enable_load_extension()] API enables or disables both the
2036
** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2037
** There should be two additional arguments.
2038
** When the first argument to this interface is 1, then only the C-API is
2039
** enabled and the SQL function remains disabled.  If the first argument to
2040
** this interface is 0, then both the C-API and the SQL function are disabled.
2041
** If the first argument is -1, then no changes are made to state of either the
2042
** C-API or the SQL function.
2043
** The second parameter is a pointer to an integer into which
2044
** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2045
** is disabled or enabled following this call.  The second parameter may
2046
** be a NULL pointer, in which case the new setting is not reported back.
2047
** </dd>
2048
**
2049
** <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
2050
** <dd> ^This option is used to change the name of the "main" database
2051
** schema.  ^The sole argument is a pointer to a constant UTF8 string
2052
** which will become the new schema name in place of "main".  ^SQLite
2053
** does not make a copy of the new main schema name string, so the application
2054
** must ensure that the argument passed into this DBCONFIG option is unchanged
2055
** until after the database connection closes.
2056
** </dd>
2057
**
2058
** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
2059
** <dd> Usually, when a database in wal mode is closed or detached from a 
2060
** database handle, SQLite checks if this will mean that there are now no 
2061
** connections at all to the database. If so, it performs a checkpoint 
2062
** operation before closing the connection. This option may be used to
2063
** override this behaviour. The first parameter passed to this operation
2064
** is an integer - positive to disable checkpoints-on-close, or zero (the
2065
** default) to enable them, and negative to leave the setting unchanged.
2066
** The second parameter is a pointer to an integer
2067
** into which is written 0 or 1 to indicate whether checkpoints-on-close
2068
** have been disabled - 0 if they are not disabled, 1 if they are.
2069
** </dd>
2070
**
2071
** <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2072
** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2073
** the [query planner stability guarantee] (QPSG).  When the QPSG is active,
2074
** a single SQL query statement will always use the same algorithm regardless
2075
** of values of [bound parameters].)^ The QPSG disables some query optimizations
2076
** that look at the values of bound parameters, which can make some queries
2077
** slower.  But the QPSG has the advantage of more predictable behavior.  With
2078
** the QPSG active, SQLite will always use the same query plan in the field as
2079
** was used during testing in the lab.
2080
** The first argument to this setting is an integer which is 0 to disable 
2081
** the QPSG, positive to enable QPSG, or negative to leave the setting
2082
** unchanged. The second parameter is a pointer to an integer into which
2083
** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
2084
** following this call.
2085
** </dd>
2086
**
2087
** <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
2088
** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not 
2089
** include output for any operations performed by trigger programs. This
2090
** option is used to set or clear (the default) a flag that governs this
2091
** behavior. The first parameter passed to this operation is an integer -
2092
** positive to enable output for trigger programs, or zero to disable it,
2093
** or negative to leave the setting unchanged.
2094
** The second parameter is a pointer to an integer into which is written 
2095
** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if 
2096
** it is not disabled, 1 if it is.  
2097
** </dd>
2098
** </dl>
2099
*/
2100
#define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
2101
#define SQLITE_DBCONFIG_LOOKASIDE             1001 /* void* int int */
2102
#define SQLITE_DBCONFIG_ENABLE_FKEY           1002 /* int int* */
2103
#define SQLITE_DBCONFIG_ENABLE_TRIGGER        1003 /* int int* */
2104
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2105
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
2106
#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE      1006 /* int int* */
2107
#define SQLITE_DBCONFIG_ENABLE_QPSG           1007 /* int int* */
2108
#define SQLITE_DBCONFIG_TRIGGER_EQP           1008 /* int int* */
2109
#define SQLITE_DBCONFIG_MAX                   1008 /* Largest DBCONFIG */
2110
2111
/*
2112
** CAPI3REF: Enable Or Disable Extended Result Codes
2113
** METHOD: sqlite3
2114
**
2115
** ^The sqlite3_extended_result_codes() routine enables or disables the
2116
** [extended result codes] feature of SQLite. ^The extended result
2117
** codes are disabled by default for historical compatibility.
2118
*/
2119
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2120
2121
/*
2122
** CAPI3REF: Last Insert Rowid
2123
** METHOD: sqlite3
2124
**
2125
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2126
** has a unique 64-bit signed
2127
** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2128
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2129
** names are not also used by explicitly declared columns. ^If
2130
** the table has a column of type [INTEGER PRIMARY KEY] then that column
2131
** is another alias for the rowid.
2132
**
2133
** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2134
** the most recent successful [INSERT] into a rowid table or [virtual table]
2135
** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
2136
** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred 
2137
** on the database connection D, then sqlite3_last_insert_rowid(D) returns 
2138
** zero.
2139
**
2140
** As well as being set automatically as rows are inserted into database
2141
** tables, the value returned by this function may be set explicitly by
2142
** [sqlite3_set_last_insert_rowid()]
2143
**
2144
** Some virtual table implementations may INSERT rows into rowid tables as
2145
** part of committing a transaction (e.g. to flush data accumulated in memory
2146
** to disk). In this case subsequent calls to this function return the rowid
2147
** associated with these internal INSERT operations, which leads to 
2148
** unintuitive results. Virtual table implementations that do write to rowid
2149
** tables in this way can avoid this problem by restoring the original 
2150
** rowid value using [sqlite3_set_last_insert_rowid()] before returning 
2151
** control to the user.
2152
**
2153
** ^(If an [INSERT] occurs within a trigger then this routine will 
2154
** return the [rowid] of the inserted row as long as the trigger is 
2155
** running. Once the trigger program ends, the value returned 
2156
** by this routine reverts to what it was before the trigger was fired.)^
2157
**
2158
** ^An [INSERT] that fails due to a constraint violation is not a
2159
** successful [INSERT] and does not change the value returned by this
2160
** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2161
** and INSERT OR ABORT make no changes to the return value of this
2162
** routine when their insertion fails.  ^(When INSERT OR REPLACE
2163
** encounters a constraint violation, it does not fail.  The
2164
** INSERT continues to completion after deleting rows that caused
2165
** the constraint problem so INSERT OR REPLACE will always change
2166
** the return value of this interface.)^
2167
**
2168
** ^For the purposes of this routine, an [INSERT] is considered to
2169
** be successful even if it is subsequently rolled back.
2170
**
2171
** This function is accessible to SQL statements via the
2172
** [last_insert_rowid() SQL function].
2173
**
2174
** If a separate thread performs a new [INSERT] on the same
2175
** database connection while the [sqlite3_last_insert_rowid()]
2176
** function is running and thus changes the last insert [rowid],
2177
** then the value returned by [sqlite3_last_insert_rowid()] is
2178
** unpredictable and might not equal either the old or the new
2179
** last insert [rowid].
2180
*/
2181
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2182
2183
/*
2184
** CAPI3REF: Set the Last Insert Rowid value.
2185
** METHOD: sqlite3
2186
**
2187
** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
2188
** set the value returned by calling sqlite3_last_insert_rowid(D) to R 
2189
** without inserting a row into the database.
2190
*/
2191
SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
2192
2193
/*
2194
** CAPI3REF: Count The Number Of Rows Modified
2195
** METHOD: sqlite3
2196
**
2197
** ^This function returns the number of rows modified, inserted or
2198
** deleted by the most recently completed INSERT, UPDATE or DELETE
2199
** statement on the database connection specified by the only parameter.
2200
** ^Executing any other type of SQL statement does not modify the value
2201
** returned by this function.
2202
**
2203
** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2204
** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 
2205
** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2206
** 
2207
** Changes to a view that are intercepted by 
2208
** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 
2209
** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 
2210
** DELETE statement run on a view is always zero. Only changes made to real 
2211
** tables are counted.
2212
**
2213
** Things are more complicated if the sqlite3_changes() function is
2214
** executed while a trigger program is running. This may happen if the
2215
** program uses the [changes() SQL function], or if some other callback
2216
** function invokes sqlite3_changes() directly. Essentially:
2217
** 
2218
** <ul>
2219
**   <li> ^(Before entering a trigger program the value returned by
2220
**        sqlite3_changes() function is saved. After the trigger program 
2221
**        has finished, the original value is restored.)^
2222
** 
2223
**   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 
2224
**        statement sets the value returned by sqlite3_changes() 
2225
**        upon completion as normal. Of course, this value will not include 
2226
**        any changes performed by sub-triggers, as the sqlite3_changes() 
2227
**        value will be saved and restored after each sub-trigger has run.)^
2228
** </ul>
2229
** 
2230
** ^This means that if the changes() SQL function (or similar) is used
2231
** by the first INSERT, UPDATE or DELETE statement within a trigger, it 
2232
** returns the value as set when the calling statement began executing.
2233
** ^If it is used by the second or subsequent such statement within a trigger 
2234
** program, the value returned reflects the number of rows modified by the 
2235
** previous INSERT, UPDATE or DELETE statement within the same trigger.
2236
**
2237
** See also the [sqlite3_total_changes()] interface, the
2238
** [count_changes pragma], and the [changes() SQL function].
2239
**
2240
** If a separate thread makes changes on the same database connection
2241
** while [sqlite3_changes()] is running then the value returned
2242
** is unpredictable and not meaningful.
2243
*/
2244
SQLITE_API int sqlite3_changes(sqlite3*);
2245
2246
/*
2247
** CAPI3REF: Total Number Of Rows Modified
2248
** METHOD: sqlite3
2249
**
2250
** ^This function returns the total number of rows inserted, modified or
2251
** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2252
** since the database connection was opened, including those executed as
2253
** part of trigger programs. ^Executing any other type of SQL statement
2254
** does not affect the value returned by sqlite3_total_changes().
2255
** 
2256
** ^Changes made as part of [foreign key actions] are included in the
2257
** count, but those made as part of REPLACE constraint resolution are
2258
** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 
2259
** are not counted.
2260
** 
2261
** See also the [sqlite3_changes()] interface, the
2262
** [count_changes pragma], and the [total_changes() SQL function].
2263
**
2264
** If a separate thread makes changes on the same database connection
2265
** while [sqlite3_total_changes()] is running then the value
2266
** returned is unpredictable and not meaningful.
2267
*/
2268
SQLITE_API int sqlite3_total_changes(sqlite3*);
2269
2270
/*
2271
** CAPI3REF: Interrupt A Long-Running Query
2272
** METHOD: sqlite3
2273
**
2274
** ^This function causes any pending database operation to abort and
2275
** return at its earliest opportunity. This routine is typically
2276
** called in response to a user action such as pressing "Cancel"
2277
** or Ctrl-C where the user wants a long query operation to halt
2278
** immediately.
2279
**
2280
** ^It is safe to call this routine from a thread different from the
2281
** thread that is currently running the database operation.  But it
2282
** is not safe to call this routine with a [database connection] that
2283
** is closed or might close before sqlite3_interrupt() returns.
2284
**
2285
** ^If an SQL operation is very nearly finished at the time when
2286
** sqlite3_interrupt() is called, then it might not have an opportunity
2287
** to be interrupted and might continue to completion.
2288
**
2289
** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2290
** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2291
** that is inside an explicit transaction, then the entire transaction
2292
** will be rolled back automatically.
2293
**
2294
** ^The sqlite3_interrupt(D) call is in effect until all currently running
2295
** SQL statements on [database connection] D complete.  ^Any new SQL statements
2296
** that are started after the sqlite3_interrupt() call and before the 
2297
** running statements reaches zero are interrupted as if they had been
2298
** running prior to the sqlite3_interrupt() call.  ^New SQL statements
2299
** that are started after the running statement count reaches zero are
2300
** not effected by the sqlite3_interrupt().
2301
** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2302
** SQL statements is a no-op and has no effect on SQL statements
2303
** that are started after the sqlite3_interrupt() call returns.
2304
*/
2305
SQLITE_API void sqlite3_interrupt(sqlite3*);
2306
2307
/*
2308
** CAPI3REF: Determine If An SQL Statement Is Complete
2309
**
2310
** These routines are useful during command-line input to determine if the
2311
** currently entered text seems to form a complete SQL statement or
2312
** if additional input is needed before sending the text into
2313
** SQLite for parsing.  ^These routines return 1 if the input string
2314
** appears to be a complete SQL statement.  ^A statement is judged to be
2315
** complete if it ends with a semicolon token and is not a prefix of a
2316
** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
2317
** string literals or quoted identifier names or comments are not
2318
** independent tokens (they are part of the token in which they are
2319
** embedded) and thus do not count as a statement terminator.  ^Whitespace
2320
** and comments that follow the final semicolon are ignored.
2321
**
2322
** ^These routines return 0 if the statement is incomplete.  ^If a
2323
** memory allocation fails, then SQLITE_NOMEM is returned.
2324
**
2325
** ^These routines do not parse the SQL statements thus
2326
** will not detect syntactically incorrect SQL.
2327
**
2328
** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 
2329
** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2330
** automatically by sqlite3_complete16().  If that initialization fails,
2331
** then the return value from sqlite3_complete16() will be non-zero
2332
** regardless of whether or not the input SQL is complete.)^
2333
**
2334
** The input to [sqlite3_complete()] must be a zero-terminated
2335
** UTF-8 string.
2336
**
2337
** The input to [sqlite3_complete16()] must be a zero-terminated
2338
** UTF-16 string in native byte order.
2339
*/
2340
SQLITE_API int sqlite3_complete(const char *sql);
2341
SQLITE_API int sqlite3_complete16(const void *sql);
2342
2343
/*
2344
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2345
** KEYWORDS: {busy-handler callback} {busy handler}
2346
** METHOD: sqlite3
2347
**
2348
** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2349
** that might be invoked with argument P whenever
2350
** an attempt is made to access a database table associated with
2351
** [database connection] D when another thread
2352
** or process has the table locked.
2353
** The sqlite3_busy_handler() interface is used to implement
2354
** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
2355
**
2356
** ^If the busy callback is NULL, then [SQLITE_BUSY]
2357
** is returned immediately upon encountering the lock.  ^If the busy callback
2358
** is not NULL, then the callback might be invoked with two arguments.
2359
**
2360
** ^The first argument to the busy handler is a copy of the void* pointer which
2361
** is the third argument to sqlite3_busy_handler().  ^The second argument to
2362
** the busy handler callback is the number of times that the busy handler has
2363
** been invoked previously for the same locking event.  ^If the
2364
** busy callback returns 0, then no additional attempts are made to
2365
** access the database and [SQLITE_BUSY] is returned
2366
** to the application.
2367
** ^If the callback returns non-zero, then another attempt
2368
** is made to access the database and the cycle repeats.
2369
**
2370
** The presence of a busy handler does not guarantee that it will be invoked
2371
** when there is lock contention. ^If SQLite determines that invoking the busy
2372
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
2373
** to the application instead of invoking the 
2374
** busy handler.
2375
** Consider a scenario where one process is holding a read lock that
2376
** it is trying to promote to a reserved lock and
2377
** a second process is holding a reserved lock that it is trying
2378
** to promote to an exclusive lock.  The first process cannot proceed
2379
** because it is blocked by the second and the second process cannot
2380
** proceed because it is blocked by the first.  If both processes
2381
** invoke the busy handlers, neither will make any progress.  Therefore,
2382
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2383
** will induce the first process to release its read lock and allow
2384
** the second process to proceed.
2385
**
2386
** ^The default busy callback is NULL.
2387
**
2388
** ^(There can only be a single busy handler defined for each
2389
** [database connection].  Setting a new busy handler clears any
2390
** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
2391
** or evaluating [PRAGMA busy_timeout=N] will change the
2392
** busy handler and thus clear any previously set busy handler.
2393
**
2394
** The busy callback should not take any actions which modify the
2395
** database connection that invoked the busy handler.  In other words,
2396
** the busy handler is not reentrant.  Any such actions
2397
** result in undefined behavior.
2398
** 
2399
** A busy handler must not close the database connection
2400
** or [prepared statement] that invoked the busy handler.
2401
*/
2402
SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
2403
2404
/*
2405
** CAPI3REF: Set A Busy Timeout
2406
** METHOD: sqlite3
2407
**
2408
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2409
** for a specified amount of time when a table is locked.  ^The handler
2410
** will sleep multiple times until at least "ms" milliseconds of sleeping
2411
** have accumulated.  ^After at least "ms" milliseconds of sleeping,
2412
** the handler returns 0 which causes [sqlite3_step()] to return
2413
** [SQLITE_BUSY].
2414
**
2415
** ^Calling this routine with an argument less than or equal to zero
2416
** turns off all busy handlers.
2417
**
2418
** ^(There can only be a single busy handler for a particular
2419
** [database connection] at any given moment.  If another busy handler
2420
** was defined  (using [sqlite3_busy_handler()]) prior to calling
2421
** this routine, that other busy handler is cleared.)^
2422
**
2423
** See also:  [PRAGMA busy_timeout]
2424
*/
2425
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
2426
2427
/*
2428
** CAPI3REF: Convenience Routines For Running Queries
2429
** METHOD: sqlite3
2430
**
2431
** This is a legacy interface that is preserved for backwards compatibility.
2432
** Use of this interface is not recommended.
2433
**
2434
** Definition: A <b>result table</b> is memory data structure created by the
2435
** [sqlite3_get_table()] interface.  A result table records the
2436
** complete query results from one or more queries.
2437
**
2438
** The table conceptually has a number of rows and columns.  But
2439
** these numbers are not part of the result table itself.  These
2440
** numbers are obtained separately.  Let N be the number of rows
2441
** and M be the number of columns.
2442
**
2443
** A result table is an array of pointers to zero-terminated UTF-8 strings.
2444
** There are (N+1)*M elements in the array.  The first M pointers point
2445
** to zero-terminated strings that  contain the names of the columns.
2446
** The remaining entries all point to query results.  NULL values result
2447
** in NULL pointers.  All other values are in their UTF-8 zero-terminated
2448
** string representation as returned by [sqlite3_column_text()].
2449
**
2450
** A result table might consist of one or more memory allocations.
2451
** It is not safe to pass a result table directly to [sqlite3_free()].
2452
** A result table should be deallocated using [sqlite3_free_table()].
2453
**
2454
** ^(As an example of the result table format, suppose a query result
2455
** is as follows:
2456
**
2457
** <blockquote><pre>
2458
**        Name        | Age
2459
**        -----------------------
2460
**        Alice       | 43
2461
**        Bob         | 28
2462
**        Cindy       | 21
2463
** </pre></blockquote>
2464
**
2465
** There are two column (M==2) and three rows (N==3).  Thus the
2466
** result table has 8 entries.  Suppose the result table is stored
2467
** in an array names azResult.  Then azResult holds this content:
2468
**
2469
** <blockquote><pre>
2470
**        azResult&#91;0] = "Name";
2471
**        azResult&#91;1] = "Age";
2472
**        azResult&#91;2] = "Alice";
2473
**        azResult&#91;3] = "43";
2474
**        azResult&#91;4] = "Bob";
2475
**        azResult&#91;5] = "28";
2476
**        azResult&#91;6] = "Cindy";
2477
**        azResult&#91;7] = "21";
2478
** </pre></blockquote>)^
2479
**
2480
** ^The sqlite3_get_table() function evaluates one or more
2481
** semicolon-separated SQL statements in the zero-terminated UTF-8
2482
** string of its 2nd parameter and returns a result table to the
2483
** pointer given in its 3rd parameter.
2484
**
2485
** After the application has finished with the result from sqlite3_get_table(),
2486
** it must pass the result table pointer to sqlite3_free_table() in order to
2487
** release the memory that was malloced.  Because of the way the
2488
** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2489
** function must not try to call [sqlite3_free()] directly.  Only
2490
** [sqlite3_free_table()] is able to release the memory properly and safely.
2491
**
2492
** The sqlite3_get_table() interface is implemented as a wrapper around
2493
** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
2494
** to any internal data structures of SQLite.  It uses only the public
2495
** interface defined here.  As a consequence, errors that occur in the
2496
** wrapper layer outside of the internal [sqlite3_exec()] call are not
2497
** reflected in subsequent calls to [sqlite3_errcode()] or
2498
** [sqlite3_errmsg()].
2499
*/
2500
SQLITE_API int sqlite3_get_table(
2501
  sqlite3 *db,          /* An open database */
2502
  const char *zSql,     /* SQL to be evaluated */
2503
  char ***pazResult,    /* Results of the query */
2504
  int *pnRow,           /* Number of result rows written here */
2505
  int *pnColumn,        /* Number of result columns written here */
2506
  char **pzErrmsg       /* Error msg written here */
2507
);
2508
SQLITE_API void sqlite3_free_table(char **result);
2509
2510
/*
2511
** CAPI3REF: Formatted String Printing Functions
2512
**
2513
** These routines are work-alikes of the "printf()" family of functions
2514
** from the standard C library.
2515
** These routines understand most of the common formatting options from
2516
** the standard library printf() 
2517
** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
2518
** See the [built-in printf()] documentation for details.
2519
**
2520
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
2521
** results into memory obtained from [sqlite3_malloc64()].
2522
** The strings returned by these two routines should be
2523
** released by [sqlite3_free()].  ^Both routines return a
2524
** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
2525
** memory to hold the resulting string.
2526
**
2527
** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2528
** the standard C library.  The result is written into the
2529
** buffer supplied as the second parameter whose size is given by
2530
** the first parameter. Note that the order of the
2531
** first two parameters is reversed from snprintf().)^  This is an
2532
** historical accident that cannot be fixed without breaking
2533
** backwards compatibility.  ^(Note also that sqlite3_snprintf()
2534
** returns a pointer to its buffer instead of the number of
2535
** characters actually written into the buffer.)^  We admit that
2536
** the number of characters written would be a more useful return
2537
** value but we cannot change the implementation of sqlite3_snprintf()
2538
** now without breaking compatibility.
2539
**
2540
** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2541
** guarantees that the buffer is always zero-terminated.  ^The first
2542
** parameter "n" is the total size of the buffer, including space for
2543
** the zero terminator.  So the longest string that can be completely
2544
** written will be n-1 characters.
2545
**
2546
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
2547
**
2548
** See also:  [built-in printf()], [printf() SQL function]
2549
*/
2550
SQLITE_API char *sqlite3_mprintf(const char*,...);
2551
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
2552
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
2553
SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
2554
2555
/*
2556
** CAPI3REF: Memory Allocation Subsystem
2557
**
2558
** The SQLite core uses these three routines for all of its own
2559
** internal memory allocation needs. "Core" in the previous sentence
2560
** does not include operating-system specific VFS implementation.  The
2561
** Windows VFS uses native malloc() and free() for some operations.
2562
**
2563
** ^The sqlite3_malloc() routine returns a pointer to a block
2564
** of memory at least N bytes in length, where N is the parameter.
2565
** ^If sqlite3_malloc() is unable to obtain sufficient free
2566
** memory, it returns a NULL pointer.  ^If the parameter N to
2567
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
2568
** a NULL pointer.
2569
**
2570
** ^The sqlite3_malloc64(N) routine works just like
2571
** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
2572
** of a signed 32-bit integer.
2573
**
2574
** ^Calling sqlite3_free() with a pointer previously returned
2575
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2576
** that it might be reused.  ^The sqlite3_free() routine is
2577
** a no-op if is called with a NULL pointer.  Passing a NULL pointer
2578
** to sqlite3_free() is harmless.  After being freed, memory
2579
** should neither be read nor written.  Even reading previously freed
2580
** memory might result in a segmentation fault or other severe error.
2581
** Memory corruption, a segmentation fault, or other severe error
2582
** might result if sqlite3_free() is called with a non-NULL pointer that
2583
** was not obtained from sqlite3_malloc() or sqlite3_realloc().
2584
**
2585
** ^The sqlite3_realloc(X,N) interface attempts to resize a
2586
** prior memory allocation X to be at least N bytes.
2587
** ^If the X parameter to sqlite3_realloc(X,N)
2588
** is a NULL pointer then its behavior is identical to calling
2589
** sqlite3_malloc(N).
2590
** ^If the N parameter to sqlite3_realloc(X,N) is zero or
2591
** negative then the behavior is exactly the same as calling
2592
** sqlite3_free(X).
2593
** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
2594
** of at least N bytes in size or NULL if insufficient memory is available.
2595
** ^If M is the size of the prior allocation, then min(N,M) bytes
2596
** of the prior allocation are copied into the beginning of buffer returned
2597
** by sqlite3_realloc(X,N) and the prior allocation is freed.
2598
** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
2599
** prior allocation is not freed.
2600
**
2601
** ^The sqlite3_realloc64(X,N) interfaces works the same as
2602
** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
2603
** of a 32-bit signed integer.
2604
**
2605
** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
2606
** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
2607
** sqlite3_msize(X) returns the size of that memory allocation in bytes.
2608
** ^The value returned by sqlite3_msize(X) might be larger than the number
2609
** of bytes requested when X was allocated.  ^If X is a NULL pointer then
2610
** sqlite3_msize(X) returns zero.  If X points to something that is not
2611
** the beginning of memory allocation, or if it points to a formerly
2612
** valid memory allocation that has now been freed, then the behavior
2613
** of sqlite3_msize(X) is undefined and possibly harmful.
2614
**
2615
** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
2616
** sqlite3_malloc64(), and sqlite3_realloc64()
2617
** is always aligned to at least an 8 byte boundary, or to a
2618
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2619
** option is used.
2620
**
2621
** In SQLite version 3.5.0 and 3.5.1, it was possible to define
2622
** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
2623
** implementation of these routines to be omitted.  That capability
2624
** is no longer provided.  Only built-in memory allocators can be used.
2625
**
2626
** Prior to SQLite version 3.7.10, the Windows OS interface layer called
2627
** the system malloc() and free() directly when converting
2628
** filenames between the UTF-8 encoding used by SQLite
2629
** and whatever filename encoding is used by the particular Windows
2630
** installation.  Memory allocation errors were detected, but
2631
** they were reported back as [SQLITE_CANTOPEN] or
2632
** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
2633
**
2634
** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2635
** must be either NULL or else pointers obtained from a prior
2636
** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2637
** not yet been released.
2638
**
2639
** The application must not read or write any part of
2640
** a block of memory after it has been released using
2641
** [sqlite3_free()] or [sqlite3_realloc()].
2642
*/
2643
SQLITE_API void *sqlite3_malloc(int);
2644
SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
2645
SQLITE_API void *sqlite3_realloc(void*, int);
2646
SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
2647
SQLITE_API void sqlite3_free(void*);
2648
SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
2649
2650
/*
2651
** CAPI3REF: Memory Allocator Statistics
2652
**
2653
** SQLite provides these two interfaces for reporting on the status
2654
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2655
** routines, which form the built-in memory allocation subsystem.
2656
**
2657
** ^The [sqlite3_memory_used()] routine returns the number of bytes
2658
** of memory currently outstanding (malloced but not freed).
2659
** ^The [sqlite3_memory_highwater()] routine returns the maximum
2660
** value of [sqlite3_memory_used()] since the high-water mark
2661
** was last reset.  ^The values returned by [sqlite3_memory_used()] and
2662
** [sqlite3_memory_highwater()] include any overhead
2663
** added by SQLite in its implementation of [sqlite3_malloc()],
2664
** but not overhead added by the any underlying system library
2665
** routines that [sqlite3_malloc()] may call.
2666
**
2667
** ^The memory high-water mark is reset to the current value of
2668
** [sqlite3_memory_used()] if and only if the parameter to
2669
** [sqlite3_memory_highwater()] is true.  ^The value returned
2670
** by [sqlite3_memory_highwater(1)] is the high-water mark
2671
** prior to the reset.
2672
*/
2673
SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
2674
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
2675
2676
/*
2677
** CAPI3REF: Pseudo-Random Number Generator
2678
**
2679
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
2680
** select random [ROWID | ROWIDs] when inserting new records into a table that
2681
** already uses the largest possible [ROWID].  The PRNG is also used for
2682
** the build-in random() and randomblob() SQL functions.  This interface allows
2683
** applications to access the same PRNG for other purposes.
2684
**
2685
** ^A call to this routine stores N bytes of randomness into buffer P.
2686
** ^The P parameter can be a NULL pointer.
2687
**
2688
** ^If this routine has not been previously called or if the previous
2689
** call had N less than one or a NULL pointer for P, then the PRNG is
2690
** seeded using randomness obtained from the xRandomness method of
2691
** the default [sqlite3_vfs] object.
2692
** ^If the previous call to this routine had an N of 1 or more and a
2693
** non-NULL P then the pseudo-randomness is generated
2694
** internally and without recourse to the [sqlite3_vfs] xRandomness
2695
** method.
2696
*/
2697
SQLITE_API void sqlite3_randomness(int N, void *P);
2698
2699
/*
2700
** CAPI3REF: Compile-Time Authorization Callbacks
2701
** METHOD: sqlite3
2702
** KEYWORDS: {authorizer callback}
2703
**
2704
** ^This routine registers an authorizer callback with a particular
2705
** [database connection], supplied in the first argument.
2706
** ^The authorizer callback is invoked as SQL statements are being compiled
2707
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
2708
** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
2709
** and [sqlite3_prepare16_v3()].  ^At various
2710
** points during the compilation process, as logic is being created
2711
** to perform various actions, the authorizer callback is invoked to
2712
** see if those actions are allowed.  ^The authorizer callback should
2713
** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
2714
** specific action but allow the SQL statement to continue to be
2715
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
2716
** rejected with an error.  ^If the authorizer callback returns
2717
** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
2718
** then the [sqlite3_prepare_v2()] or equivalent call that triggered
2719
** the authorizer will fail with an error message.
2720
**
2721
** When the callback returns [SQLITE_OK], that means the operation
2722
** requested is ok.  ^When the callback returns [SQLITE_DENY], the
2723
** [sqlite3_prepare_v2()] or equivalent call that triggered the
2724
** authorizer will fail with an error message explaining that
2725
** access is denied. 
2726
**
2727
** ^The first parameter to the authorizer callback is a copy of the third
2728
** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
2729
** to the callback is an integer [SQLITE_COPY | action code] that specifies
2730
** the particular action to be authorized. ^The third through sixth parameters
2731
** to the callback are either NULL pointers or zero-terminated strings
2732
** that contain additional details about the action to be authorized.
2733
** Applications must always be prepared to encounter a NULL pointer in any
2734
** of the third through the sixth parameters of the authorization callback.
2735
**
2736
** ^If the action code is [SQLITE_READ]
2737
** and the callback returns [SQLITE_IGNORE] then the
2738
** [prepared statement] statement is constructed to substitute
2739
** a NULL value in place of the table column that would have
2740
** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
2741
** return can be used to deny an untrusted user access to individual
2742
** columns of a table.
2743
** ^When a table is referenced by a [SELECT] but no column values are
2744
** extracted from that table (for example in a query like
2745
** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
2746
** is invoked once for that table with a column name that is an empty string.
2747
** ^If the action code is [SQLITE_DELETE] and the callback returns
2748
** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
2749
** [truncate optimization] is disabled and all rows are deleted individually.
2750
**
2751
** An authorizer is used when [sqlite3_prepare | preparing]
2752
** SQL statements from an untrusted source, to ensure that the SQL statements
2753
** do not try to access data they are not allowed to see, or that they do not
2754
** try to execute malicious statements that damage the database.  For
2755
** example, an application may allow a user to enter arbitrary
2756
** SQL queries for evaluation by a database.  But the application does
2757
** not want the user to be able to make arbitrary changes to the
2758
** database.  An authorizer could then be put in place while the
2759
** user-entered SQL is being [sqlite3_prepare | prepared] that
2760
** disallows everything except [SELECT] statements.
2761
**
2762
** Applications that need to process SQL from untrusted sources
2763
** might also consider lowering resource limits using [sqlite3_limit()]
2764
** and limiting database size using the [max_page_count] [PRAGMA]
2765
** in addition to using an authorizer.
2766
**
2767
** ^(Only a single authorizer can be in place on a database connection
2768
** at a time.  Each call to sqlite3_set_authorizer overrides the
2769
** previous call.)^  ^Disable the authorizer by installing a NULL callback.
2770
** The authorizer is disabled by default.
2771
**
2772
** The authorizer callback must not do anything that will modify
2773
** the database connection that invoked the authorizer callback.
2774
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2775
** database connections for the meaning of "modify" in this paragraph.
2776
**
2777
** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
2778
** statement might be re-prepared during [sqlite3_step()] due to a 
2779
** schema change.  Hence, the application should ensure that the
2780
** correct authorizer callback remains in place during the [sqlite3_step()].
2781
**
2782
** ^Note that the authorizer callback is invoked only during
2783
** [sqlite3_prepare()] or its variants.  Authorization is not
2784
** performed during statement evaluation in [sqlite3_step()], unless
2785
** as stated in the previous paragraph, sqlite3_step() invokes
2786
** sqlite3_prepare_v2() to reprepare a statement after a schema change.
2787
*/
2788
SQLITE_API int sqlite3_set_authorizer(
2789
  sqlite3*,
2790
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
2791
  void *pUserData
2792
);
2793
2794
/*
2795
** CAPI3REF: Authorizer Return Codes
2796
**
2797
** The [sqlite3_set_authorizer | authorizer callback function] must
2798
** return either [SQLITE_OK] or one of these two constants in order
2799
** to signal SQLite whether or not the action is permitted.  See the
2800
** [sqlite3_set_authorizer | authorizer documentation] for additional
2801
** information.
2802
**
2803
** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
2804
** returned from the [sqlite3_vtab_on_conflict()] interface.
2805
*/
2806
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
2807
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
2808
2809
/*
2810
** CAPI3REF: Authorizer Action Codes
2811
**
2812
** The [sqlite3_set_authorizer()] interface registers a callback function
2813
** that is invoked to authorize certain SQL statement actions.  The
2814
** second parameter to the callback is an integer code that specifies
2815
** what action is being authorized.  These are the integer action codes that
2816
** the authorizer callback may be passed.
2817
**
2818
** These action code values signify what kind of operation is to be
2819
** authorized.  The 3rd and 4th parameters to the authorization
2820
** callback function will be parameters or NULL depending on which of these
2821
** codes is used as the second parameter.  ^(The 5th parameter to the
2822
** authorizer callback is the name of the database ("main", "temp",
2823
** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
2824
** is the name of the inner-most trigger or view that is responsible for
2825
** the access attempt or NULL if this access attempt is directly from
2826
** top-level SQL code.
2827
*/
2828
/******************************************* 3rd ************ 4th ***********/
2829
#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
2830
#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
2831
#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
2832
#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
2833
#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
2834
#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
2835
#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
2836
#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
2837
#define SQLITE_DELETE                9   /* Table Name      NULL            */
2838
#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
2839
#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
2840
#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
2841
#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
2842
#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
2843
#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
2844
#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
2845
#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
2846
#define SQLITE_INSERT               18   /* Table Name      NULL            */
2847
#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
2848
#define SQLITE_READ                 20   /* Table Name      Column Name     */
2849
#define SQLITE_SELECT               21   /* NULL            NULL            */
2850
#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
2851
#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
2852
#define SQLITE_ATTACH               24   /* Filename        NULL            */
2853
#define SQLITE_DETACH               25   /* Database Name   NULL            */
2854
#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
2855
#define SQLITE_REINDEX              27   /* Index Name      NULL            */
2856
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
2857
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
2858
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
2859
#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
2860
#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
2861
#define SQLITE_COPY                  0   /* No longer used */
2862
#define SQLITE_RECURSIVE            33   /* NULL            NULL            */
2863
2864
/*
2865
** CAPI3REF: Tracing And Profiling Functions
2866
** METHOD: sqlite3
2867
**
2868
** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
2869
** instead of the routines described here.
2870
**
2871
** These routines register callback functions that can be used for
2872
** tracing and profiling the execution of SQL statements.
2873
**
2874
** ^The callback function registered by sqlite3_trace() is invoked at
2875
** various times when an SQL statement is being run by [sqlite3_step()].
2876
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
2877
** SQL statement text as the statement first begins executing.
2878
** ^(Additional sqlite3_trace() callbacks might occur
2879
** as each triggered subprogram is entered.  The callbacks for triggers
2880
** contain a UTF-8 SQL comment that identifies the trigger.)^
2881
**
2882
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
2883
** the length of [bound parameter] expansion in the output of sqlite3_trace().
2884
**
2885
** ^The callback function registered by sqlite3_profile() is invoked
2886
** as each SQL statement finishes.  ^The profile callback contains
2887
** the original statement text and an estimate of wall-clock time
2888
** of how long that statement took to run.  ^The profile callback
2889
** time is in units of nanoseconds, however the current implementation
2890
** is only capable of millisecond resolution so the six least significant
2891
** digits in the time are meaningless.  Future versions of SQLite
2892
** might provide greater resolution on the profiler callback.  The
2893
** sqlite3_profile() function is considered experimental and is
2894
** subject to change in future versions of SQLite.
2895
*/
2896
SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
2897
   void(*xTrace)(void*,const char*), void*);
2898
SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
2899
   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
2900
2901
/*
2902
** CAPI3REF: SQL Trace Event Codes
2903
** KEYWORDS: SQLITE_TRACE
2904
**
2905
** These constants identify classes of events that can be monitored
2906
** using the [sqlite3_trace_v2()] tracing logic.  The M argument
2907
** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
2908
** the following constants.  ^The first argument to the trace callback
2909
** is one of the following constants.
2910
**
2911
** New tracing constants may be added in future releases.
2912
**
2913
** ^A trace callback has four arguments: xCallback(T,C,P,X).
2914
** ^The T argument is one of the integer type codes above.
2915
** ^The C argument is a copy of the context pointer passed in as the
2916
** fourth argument to [sqlite3_trace_v2()].
2917
** The P and X arguments are pointers whose meanings depend on T.
2918
**
2919
** <dl>
2920
** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
2921
** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
2922
** first begins running and possibly at other times during the
2923
** execution of the prepared statement, such as at the start of each
2924
** trigger subprogram. ^The P argument is a pointer to the
2925
** [prepared statement]. ^The X argument is a pointer to a string which
2926
** is the unexpanded SQL text of the prepared statement or an SQL comment 
2927
** that indicates the invocation of a trigger.  ^The callback can compute
2928
** the same text that would have been returned by the legacy [sqlite3_trace()]
2929
** interface by using the X argument when X begins with "--" and invoking
2930
** [sqlite3_expanded_sql(P)] otherwise.
2931
**
2932
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
2933
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
2934
** information as is provided by the [sqlite3_profile()] callback.
2935
** ^The P argument is a pointer to the [prepared statement] and the
2936
** X argument points to a 64-bit integer which is the estimated of
2937
** the number of nanosecond that the prepared statement took to run.
2938
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
2939
**
2940
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
2941
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
2942
** statement generates a single row of result.  
2943
** ^The P argument is a pointer to the [prepared statement] and the
2944
** X argument is unused.
2945
**
2946
** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
2947
** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
2948
** connection closes.
2949
** ^The P argument is a pointer to the [database connection] object
2950
** and the X argument is unused.
2951
** </dl>
2952
*/
2953
#define SQLITE_TRACE_STMT       0x01
2954
#define SQLITE_TRACE_PROFILE    0x02
2955
#define SQLITE_TRACE_ROW        0x04
2956
#define SQLITE_TRACE_CLOSE      0x08
2957
2958
/*
2959
** CAPI3REF: SQL Trace Hook
2960
** METHOD: sqlite3
2961
**
2962
** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
2963
** function X against [database connection] D, using property mask M
2964
** and context pointer P.  ^If the X callback is
2965
** NULL or if the M mask is zero, then tracing is disabled.  The
2966
** M argument should be the bitwise OR-ed combination of
2967
** zero or more [SQLITE_TRACE] constants.
2968
**
2969
** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides 
2970
** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().
2971
**
2972
** ^The X callback is invoked whenever any of the events identified by 
2973
** mask M occur.  ^The integer return value from the callback is currently
2974
** ignored, though this may change in future releases.  Callback
2975
** implementations should return zero to ensure future compatibility.
2976
**
2977
** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
2978
** ^The T argument is one of the [SQLITE_TRACE]
2979
** constants to indicate why the callback was invoked.
2980
** ^The C argument is a copy of the context pointer.
2981
** The P and X arguments are pointers whose meanings depend on T.
2982
**
2983
** The sqlite3_trace_v2() interface is intended to replace the legacy
2984
** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
2985
** are deprecated.
2986
*/
2987
SQLITE_API int sqlite3_trace_v2(
2988
  sqlite3*,
2989
  unsigned uMask,
2990
  int(*xCallback)(unsigned,void*,void*,void*),
2991
  void *pCtx
2992
);
2993
2994
/*
2995
** CAPI3REF: Query Progress Callbacks
2996
** METHOD: sqlite3
2997
**
2998
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
2999
** function X to be invoked periodically during long running calls to
3000
** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
3001
** database connection D.  An example use for this
3002
** interface is to keep a GUI updated during a large query.
3003
**
3004
** ^The parameter P is passed through as the only parameter to the 
3005
** callback function X.  ^The parameter N is the approximate number of 
3006
** [virtual machine instructions] that are evaluated between successive
3007
** invocations of the callback X.  ^If N is less than one then the progress
3008
** handler is disabled.
3009
**
3010
** ^Only a single progress handler may be defined at one time per
3011
** [database connection]; setting a new progress handler cancels the
3012
** old one.  ^Setting parameter X to NULL disables the progress handler.
3013
** ^The progress handler is also disabled by setting N to a value less
3014
** than 1.
3015
**
3016
** ^If the progress callback returns non-zero, the operation is
3017
** interrupted.  This feature can be used to implement a
3018
** "Cancel" button on a GUI progress dialog box.
3019
**
3020
** The progress handler callback must not do anything that will modify
3021
** the database connection that invoked the progress handler.
3022
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3023
** database connections for the meaning of "modify" in this paragraph.
3024
**
3025
*/
3026
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3027
3028
/*
3029
** CAPI3REF: Opening A New Database Connection
3030
** CONSTRUCTOR: sqlite3
3031
**
3032
** ^These routines open an SQLite database file as specified by the 
3033
** filename argument. ^The filename argument is interpreted as UTF-8 for
3034
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3035
** order for sqlite3_open16(). ^(A [database connection] handle is usually
3036
** returned in *ppDb, even if an error occurs.  The only exception is that
3037
** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3038
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3039
** object.)^ ^(If the database is opened (and/or created) successfully, then
3040
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
3041
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3042
** an English language description of the error following a failure of any
3043
** of the sqlite3_open() routines.
3044
**
3045
** ^The default encoding will be UTF-8 for databases created using
3046
** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
3047
** created using sqlite3_open16() will be UTF-16 in the native byte order.
3048
**
3049
** Whether or not an error occurs when it is opened, resources
3050
** associated with the [database connection] handle should be released by
3051
** passing it to [sqlite3_close()] when it is no longer required.
3052
**
3053
** The sqlite3_open_v2() interface works like sqlite3_open()
3054
** except that it accepts two additional parameters for additional control
3055
** over the new database connection.  ^(The flags parameter to
3056
** sqlite3_open_v2() can take one of
3057
** the following three values, optionally combined with the 
3058
** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
3059
** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
3060
**
3061
** <dl>
3062
** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3063
** <dd>The database is opened in read-only mode.  If the database does not
3064
** already exist, an error is returned.</dd>)^
3065
**
3066
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3067
** <dd>The database is opened for reading and writing if possible, or reading
3068
** only if the file is write protected by the operating system.  In either
3069
** case the database must already exist, otherwise an error is returned.</dd>)^
3070
**
3071
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3072
** <dd>The database is opened for reading and writing, and is created if
3073
** it does not already exist. This is the behavior that is always used for
3074
** sqlite3_open() and sqlite3_open16().</dd>)^
3075
** </dl>
3076
**
3077
** If the 3rd parameter to sqlite3_open_v2() is not one of the
3078
** combinations shown above optionally combined with other
3079
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3080
** then the behavior is undefined.
3081
**
3082
** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
3083
** opens in the multi-thread [threading mode] as long as the single-thread
3084
** mode has not been set at compile-time or start-time.  ^If the
3085
** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
3086
** in the serialized [threading mode] unless single-thread was
3087
** previously selected at compile-time or start-time.
3088
** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
3089
** eligible to use [shared cache mode], regardless of whether or not shared
3090
** cache is enabled using [sqlite3_enable_shared_cache()].  ^The
3091
** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
3092
** participate in [shared cache mode] even if it is enabled.
3093
**
3094
** ^The fourth parameter to sqlite3_open_v2() is the name of the
3095
** [sqlite3_vfs] object that defines the operating system interface that
3096
** the new database connection should use.  ^If the fourth parameter is
3097
** a NULL pointer then the default [sqlite3_vfs] object is used.
3098
**
3099
** ^If the filename is ":memory:", then a private, temporary in-memory database
3100
** is created for the connection.  ^This in-memory database will vanish when
3101
** the database connection is closed.  Future versions of SQLite might
3102
** make use of additional special filenames that begin with the ":" character.
3103
** It is recommended that when a database filename actually does begin with
3104
** a ":" character you should prefix the filename with a pathname such as
3105
** "./" to avoid ambiguity.
3106
**
3107
** ^If the filename is an empty string, then a private, temporary
3108
** on-disk database will be created.  ^This private database will be
3109
** automatically deleted as soon as the database connection is closed.
3110
**
3111
** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3112
**
3113
** ^If [URI filename] interpretation is enabled, and the filename argument
3114
** begins with "file:", then the filename is interpreted as a URI. ^URI
3115
** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3116
** set in the third argument to sqlite3_open_v2(), or if it has
3117
** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3118
** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3119
** URI filename interpretation is turned off
3120
** by default, but future releases of SQLite might enable URI filename
3121
** interpretation by default.  See "[URI filenames]" for additional
3122
** information.
3123
**
3124
** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3125
** authority, then it must be either an empty string or the string 
3126
** "localhost". ^If the authority is not an empty string or "localhost", an 
3127
** error is returned to the caller. ^The fragment component of a URI, if 
3128
** present, is ignored.
3129
**
3130
** ^SQLite uses the path component of the URI as the name of the disk file
3131
** which contains the database. ^If the path begins with a '/' character, 
3132
** then it is interpreted as an absolute path. ^If the path does not begin 
3133
** with a '/' (meaning that the authority section is omitted from the URI)
3134
** then the path is interpreted as a relative path. 
3135
** ^(On windows, the first component of an absolute path 
3136
** is a drive specification (e.g. "C:").)^
3137
**
3138
** [[core URI query parameters]]
3139
** The query component of a URI may contain parameters that are interpreted
3140
** either by SQLite itself, or by a [VFS | custom VFS implementation].
3141
** SQLite and its built-in [VFSes] interpret the
3142
** following query parameters:
3143
**
3144
** <ul>
3145
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3146
**     a VFS object that provides the operating system interface that should
3147
**     be used to access the database file on disk. ^If this option is set to
3148
**     an empty string the default VFS object is used. ^Specifying an unknown
3149
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3150
**     present, then the VFS specified by the option takes precedence over
3151
**     the value passed as the fourth parameter to sqlite3_open_v2().
3152
**
3153
**   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3154
**     "rwc", or "memory". Attempting to set it to any other value is
3155
**     an error)^. 
3156
**     ^If "ro" is specified, then the database is opened for read-only 
3157
**     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 
3158
**     third argument to sqlite3_open_v2(). ^If the mode option is set to 
3159
**     "rw", then the database is opened for read-write (but not create) 
3160
**     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 
3161
**     been set. ^Value "rwc" is equivalent to setting both 
3162
**     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
3163
**     set to "memory" then a pure [in-memory database] that never reads
3164
**     or writes from disk is used. ^It is an error to specify a value for
3165
**     the mode parameter that is less restrictive than that specified by
3166
**     the flags passed in the third parameter to sqlite3_open_v2().
3167
**
3168
**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3169
**     "private". ^Setting it to "shared" is equivalent to setting the
3170
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3171
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is 
3172
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3173
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3174
**     a URI filename, its value overrides any behavior requested by setting
3175
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3176
**
3177
**  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3178
**     [powersafe overwrite] property does or does not apply to the
3179
**     storage media on which the database file resides.
3180
**
3181
**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3182
**     which if set disables file locking in rollback journal modes.  This
3183
**     is useful for accessing a database on a filesystem that does not
3184
**     support locking.  Caution:  Database corruption might result if two
3185
**     or more processes write to the same database and any one of those
3186
**     processes uses nolock=1.
3187
**
3188
**  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3189
**     parameter that indicates that the database file is stored on
3190
**     read-only media.  ^When immutable is set, SQLite assumes that the
3191
**     database file cannot be changed, even by a process with higher
3192
**     privilege, and so the database is opened read-only and all locking
3193
**     and change detection is disabled.  Caution: Setting the immutable
3194
**     property on a database file that does in fact change can result
3195
**     in incorrect query results and/or [SQLITE_CORRUPT] errors.
3196
**     See also: [SQLITE_IOCAP_IMMUTABLE].
3197
**       
3198
** </ul>
3199
**
3200
** ^Specifying an unknown parameter in the query component of a URI is not an
3201
** error.  Future versions of SQLite might understand additional query
3202
** parameters.  See "[query parameters with special meaning to SQLite]" for
3203
** additional information.
3204
**
3205
** [[URI filename examples]] <h3>URI filename examples</h3>
3206
**
3207
** <table border="1" align=center cellpadding=5>
3208
** <tr><th> URI filenames <th> Results
3209
** <tr><td> file:data.db <td> 
3210
**          Open the file "data.db" in the current directory.
3211
** <tr><td> file:/home/fred/data.db<br>
3212
**          file:///home/fred/data.db <br> 
3213
**          file://localhost/home/fred/data.db <br> <td> 
3214
**          Open the database file "/home/fred/data.db".
3215
** <tr><td> file://darkstar/home/fred/data.db <td> 
3216
**          An error. "darkstar" is not a recognized authority.
3217
** <tr><td style="white-space:nowrap"> 
3218
**          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3219
**     <td> Windows only: Open the file "data.db" on fred's desktop on drive
3220
**          C:. Note that the %20 escaping in this example is not strictly 
3221
**          necessary - space characters can be used literally
3222
**          in URI filenames.
3223
** <tr><td> file:data.db?mode=ro&cache=private <td> 
3224
**          Open file "data.db" in the current directory for read-only access.
3225
**          Regardless of whether or not shared-cache mode is enabled by
3226
**          default, use a private cache.
3227
** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3228
**          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3229
**          that uses dot-files in place of posix advisory locking.
3230
** <tr><td> file:data.db?mode=readonly <td> 
3231
**          An error. "readonly" is not a valid option for the "mode" parameter.
3232
** </table>
3233
**
3234
** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3235
** query components of a URI. A hexadecimal escape sequence consists of a
3236
** percent sign - "%" - followed by exactly two hexadecimal digits 
3237
** specifying an octet value. ^Before the path or query components of a
3238
** URI filename are interpreted, they are encoded using UTF-8 and all 
3239
** hexadecimal escape sequences replaced by a single byte containing the
3240
** corresponding octet. If this process generates an invalid UTF-8 encoding,
3241
** the results are undefined.
3242
**
3243
** <b>Note to Windows users:</b>  The encoding used for the filename argument
3244
** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3245
** codepage is currently defined.  Filenames containing international
3246
** characters must be converted to UTF-8 prior to passing them into
3247
** sqlite3_open() or sqlite3_open_v2().
3248
**
3249
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
3250
** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
3251
** features that require the use of temporary files may fail.
3252
**
3253
** See also: [sqlite3_temp_directory]
3254
*/
3255
SQLITE_API int sqlite3_open(
3256
  const char *filename,   /* Database filename (UTF-8) */
3257
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3258
);
3259
SQLITE_API int sqlite3_open16(
3260
  const void *filename,   /* Database filename (UTF-16) */
3261
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3262
);
3263
SQLITE_API int sqlite3_open_v2(
3264
  const char *filename,   /* Database filename (UTF-8) */
3265
  sqlite3 **ppDb,         /* OUT: SQLite db handle */
3266
  int flags,              /* Flags */
3267
  const char *zVfs        /* Name of VFS module to use */
3268
);
3269
3270
/*
3271
** CAPI3REF: Obtain Values For URI Parameters
3272
**
3273
** These are utility routines, useful to VFS implementations, that check
3274
** to see if a database file was a URI that contained a specific query 
3275
** parameter, and if so obtains the value of that query parameter.
3276
**
3277
** If F is the database filename pointer passed into the xOpen() method of 
3278
** a VFS implementation when the flags parameter to xOpen() has one or 
3279
** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
3280
** P is the name of the query parameter, then
3281
** sqlite3_uri_parameter(F,P) returns the value of the P
3282
** parameter if it exists or a NULL pointer if P does not appear as a 
3283
** query parameter on F.  If P is a query parameter of F
3284
** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3285
** a pointer to an empty string.
3286
**
3287
** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3288
** parameter and returns true (1) or false (0) according to the value
3289
** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3290
** value of query parameter P is one of "yes", "true", or "on" in any
3291
** case or if the value begins with a non-zero number.  The 
3292
** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3293
** query parameter P is one of "no", "false", or "off" in any case or
3294
** if the value begins with a numeric zero.  If P is not a query
3295
** parameter on F or if the value of P is does not match any of the
3296
** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
3297
**
3298
** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3299
** 64-bit signed integer and returns that integer, or D if P does not
3300
** exist.  If the value of P is something other than an integer, then
3301
** zero is returned.
3302
** 
3303
** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
3304
** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
3305
** is not a database file pathname pointer that SQLite passed into the xOpen
3306
** VFS method, then the behavior of this routine is undefined and probably
3307
** undesirable.
3308
*/
3309
SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
3310
SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
3311
SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
3312
3313
3314
/*
3315
** CAPI3REF: Error Codes And Messages
3316
** METHOD: sqlite3
3317
**
3318
** ^If the most recent sqlite3_* API call associated with 
3319
** [database connection] D failed, then the sqlite3_errcode(D) interface
3320
** returns the numeric [result code] or [extended result code] for that
3321
** API call.
3322
** If the most recent API call was successful,
3323
** then the return value from sqlite3_errcode() is undefined.
3324
** ^The sqlite3_extended_errcode()
3325
** interface is the same except that it always returns the 
3326
** [extended result code] even when extended result codes are
3327
** disabled.
3328
**
3329
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3330
** text that describes the error, as either UTF-8 or UTF-16 respectively.
3331
** ^(Memory to hold the error message string is managed internally.
3332
** The application does not need to worry about freeing the result.
3333
** However, the error string might be overwritten or deallocated by
3334
** subsequent calls to other SQLite interface functions.)^
3335
**
3336
** ^The sqlite3_errstr() interface returns the English-language text
3337
** that describes the [result code], as UTF-8.
3338
** ^(Memory to hold the error message string is managed internally
3339
** and must not be freed by the application)^.
3340
**
3341
** When the serialized [threading mode] is in use, it might be the
3342
** case that a second error occurs on a separate thread in between
3343
** the time of the first error and the call to these interfaces.
3344
** When that happens, the second error will be reported since these
3345
** interfaces always report the most recent result.  To avoid
3346
** this, each thread can obtain exclusive use of the [database connection] D
3347
** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
3348
** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
3349
** all calls to the interfaces listed here are completed.
3350
**
3351
** If an interface fails with SQLITE_MISUSE, that means the interface
3352
** was invoked incorrectly by the application.  In that case, the
3353
** error code and message may or may not be set.
3354
*/
3355
SQLITE_API int sqlite3_errcode(sqlite3 *db);
3356
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
3357
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
3358
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
3359
SQLITE_API const char *sqlite3_errstr(int);
3360
3361
/*
3362
** CAPI3REF: Prepared Statement Object
3363
** KEYWORDS: {prepared statement} {prepared statements}
3364
**
3365
** An instance of this object represents a single SQL statement that
3366
** has been compiled into binary form and is ready to be evaluated.
3367
**
3368
** Think of each SQL statement as a separate computer program.  The
3369
** original SQL text is source code.  A prepared statement object 
3370
** is the compiled object code.  All SQL must be converted into a
3371
** prepared statement before it can be run.
3372
**
3373
** The life-cycle of a prepared statement object usually goes like this:
3374
**
3375
** <ol>
3376
** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
3377
** <li> Bind values to [parameters] using the sqlite3_bind_*()
3378
**      interfaces.
3379
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
3380
** <li> Reset the prepared statement using [sqlite3_reset()] then go back
3381
**      to step 2.  Do this zero or more times.
3382
** <li> Destroy the object using [sqlite3_finalize()].
3383
** </ol>
3384
*/
3385
typedef struct sqlite3_stmt sqlite3_stmt;
3386
3387
/*
3388
** CAPI3REF: Run-time Limits
3389
** METHOD: sqlite3
3390
**
3391
** ^(This interface allows the size of various constructs to be limited
3392
** on a connection by connection basis.  The first parameter is the
3393
** [database connection] whose limit is to be set or queried.  The
3394
** second parameter is one of the [limit categories] that define a
3395
** class of constructs to be size limited.  The third parameter is the
3396
** new limit for that construct.)^
3397
**
3398
** ^If the new limit is a negative number, the limit is unchanged.
3399
** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 
3400
** [limits | hard upper bound]
3401
** set at compile-time by a C preprocessor macro called
3402
** [limits | SQLITE_MAX_<i>NAME</i>].
3403
** (The "_LIMIT_" in the name is changed to "_MAX_".))^
3404
** ^Attempts to increase a limit above its hard upper bound are
3405
** silently truncated to the hard upper bound.
3406
**
3407
** ^Regardless of whether or not the limit was changed, the 
3408
** [sqlite3_limit()] interface returns the prior value of the limit.
3409
** ^Hence, to find the current value of a limit without changing it,
3410
** simply invoke this interface with the third parameter set to -1.
3411
**
3412
** Run-time limits are intended for use in applications that manage
3413
** both their own internal database and also databases that are controlled
3414
** by untrusted external sources.  An example application might be a
3415
** web browser that has its own databases for storing history and
3416
** separate databases controlled by JavaScript applications downloaded
3417
** off the Internet.  The internal databases can be given the
3418
** large, default limits.  Databases managed by external sources can
3419
** be given much smaller limits designed to prevent a denial of service
3420
** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
3421
** interface to further control untrusted SQL.  The size of the database
3422
** created by an untrusted script can be contained using the
3423
** [max_page_count] [PRAGMA].
3424
**
3425
** New run-time limit categories may be added in future releases.
3426
*/
3427
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
3428
3429
/*
3430
** CAPI3REF: Run-Time Limit Categories
3431
** KEYWORDS: {limit category} {*limit categories}
3432
**
3433
** These constants define various performance limits
3434
** that can be lowered at run-time using [sqlite3_limit()].
3435
** The synopsis of the meanings of the various limits is shown below.
3436
** Additional information is available at [limits | Limits in SQLite].
3437
**
3438
** <dl>
3439
** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
3440
** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
3441
**
3442
** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
3443
** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
3444
**
3445
** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
3446
** <dd>The maximum number of columns in a table definition or in the
3447
** result set of a [SELECT] or the maximum number of columns in an index
3448
** or in an ORDER BY or GROUP BY clause.</dd>)^
3449
**
3450
** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3451
** <dd>The maximum depth of the parse tree on any expression.</dd>)^
3452
**
3453
** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3454
** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
3455
**
3456
** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
3457
** <dd>The maximum number of instructions in a virtual machine program
3458
** used to implement an SQL statement.  If [sqlite3_prepare_v2()] or
3459
** the equivalent tries to allocate space for more than this many opcodes
3460
** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
3461
**
3462
** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3463
** <dd>The maximum number of arguments on a function.</dd>)^
3464
**
3465
** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3466
** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
3467
**
3468
** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3469
** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3470
** <dd>The maximum length of the pattern argument to the [LIKE] or
3471
** [GLOB] operators.</dd>)^
3472
**
3473
** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3474
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3475
** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3476
**
3477
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3478
** <dd>The maximum depth of recursion for triggers.</dd>)^
3479
**
3480
** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
3481
** <dd>The maximum number of auxiliary worker threads that a single
3482
** [prepared statement] may start.</dd>)^
3483
** </dl>
3484
*/
3485
#define SQLITE_LIMIT_LENGTH                    0
3486
#define SQLITE_LIMIT_SQL_LENGTH                1
3487
#define SQLITE_LIMIT_COLUMN                    2
3488
#define SQLITE_LIMIT_EXPR_DEPTH                3
3489
#define SQLITE_LIMIT_COMPOUND_SELECT           4
3490
#define SQLITE_LIMIT_VDBE_OP                   5
3491
#define SQLITE_LIMIT_FUNCTION_ARG              6
3492
#define SQLITE_LIMIT_ATTACHED                  7
3493
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
3494
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
3495
#define SQLITE_LIMIT_TRIGGER_DEPTH            10
3496
#define SQLITE_LIMIT_WORKER_THREADS           11
3497
3498
/*
3499
** CAPI3REF: Prepare Flags
3500
**
3501
** These constants define various flags that can be passed into
3502
** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
3503
** [sqlite3_prepare16_v3()] interfaces.
3504
**
3505
** New flags may be added in future releases of SQLite.
3506
**
3507
** <dl>
3508
** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
3509
** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
3510
** that the prepared statement will be retained for a long time and
3511
** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
3512
** and [sqlite3_prepare16_v3()] assume that the prepared statement will 
3513
** be used just once or at most a few times and then destroyed using
3514
** [sqlite3_finalize()] relatively soon. The current implementation acts
3515
** on this hint by avoiding the use of [lookaside memory] so as not to
3516
** deplete the limited store of lookaside memory. Future versions of
3517
** SQLite may act on this hint differently.
3518
** </dl>
3519
*/
3520
#define SQLITE_PREPARE_PERSISTENT              0x01
3521
3522
/*
3523
** CAPI3REF: Compiling An SQL Statement
3524
** KEYWORDS: {SQL statement compiler}
3525
** METHOD: sqlite3
3526
** CONSTRUCTOR: sqlite3_stmt
3527
**
3528
** To execute an SQL statement, it must first be compiled into a byte-code
3529
** program using one of these routines.  Or, in other words, these routines
3530
** are constructors for the [prepared statement] object.
3531
**
3532
** The preferred routine to use is [sqlite3_prepare_v2()].  The
3533
** [sqlite3_prepare()] interface is legacy and should be avoided.
3534
** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
3535
** for special purposes.
3536
**
3537
** The use of the UTF-8 interfaces is preferred, as SQLite currently
3538
** does all parsing using UTF-8.  The UTF-16 interfaces are provided
3539
** as a convenience.  The UTF-16 interfaces work by converting the
3540
** input text into UTF-8, then invoking the corresponding UTF-8 interface.
3541
**
3542
** The first argument, "db", is a [database connection] obtained from a
3543
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
3544
** [sqlite3_open16()].  The database connection must not have been closed.
3545
**
3546
** The second argument, "zSql", is the statement to be compiled, encoded
3547
** as either UTF-8 or UTF-16.  The sqlite3_prepare(), sqlite3_prepare_v2(),
3548
** and sqlite3_prepare_v3()
3549
** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
3550
** and sqlite3_prepare16_v3() use UTF-16.
3551
**
3552
** ^If the nByte argument is negative, then zSql is read up to the
3553
** first zero terminator. ^If nByte is positive, then it is the
3554
** number of bytes read from zSql.  ^If nByte is zero, then no prepared
3555
** statement is generated.
3556
** If the caller knows that the supplied string is nul-terminated, then
3557
** there is a small performance advantage to passing an nByte parameter that
3558
** is the number of bytes in the input string <i>including</i>
3559
** the nul-terminator.
3560
**
3561
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
3562
** past the end of the first SQL statement in zSql.  These routines only
3563
** compile the first statement in zSql, so *pzTail is left pointing to
3564
** what remains uncompiled.
3565
**
3566
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
3567
** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
3568
** to NULL.  ^If the input text contains no SQL (if the input is an empty
3569
** string or a comment) then *ppStmt is set to NULL.
3570
** The calling procedure is responsible for deleting the compiled
3571
** SQL statement using [sqlite3_finalize()] after it has finished with it.
3572
** ppStmt may not be NULL.
3573
**
3574
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
3575
** otherwise an [error code] is returned.
3576
**
3577
** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
3578
** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
3579
** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
3580
** are retained for backwards compatibility, but their use is discouraged.
3581
** ^In the "vX" interfaces, the prepared statement
3582
** that is returned (the [sqlite3_stmt] object) contains a copy of the
3583
** original SQL text. This causes the [sqlite3_step()] interface to
3584
** behave differently in three ways:
3585
**
3586
** <ol>
3587
** <li>
3588
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
3589
** always used to do, [sqlite3_step()] will automatically recompile the SQL
3590
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
3591
** retries will occur before sqlite3_step() gives up and returns an error.
3592
** </li>
3593
**
3594
** <li>
3595
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
3596
** [error codes] or [extended error codes].  ^The legacy behavior was that
3597
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
3598
** and the application would have to make a second call to [sqlite3_reset()]
3599
** in order to find the underlying cause of the problem. With the "v2" prepare
3600
** interfaces, the underlying reason for the error is returned immediately.
3601
** </li>
3602
**
3603
** <li>
3604
** ^If the specific value bound to [parameter | host parameter] in the 
3605
** WHERE clause might influence the choice of query plan for a statement,
3606
** then the statement will be automatically recompiled, as if there had been 
3607
** a schema change, on the first  [sqlite3_step()] call following any change
3608
** to the [sqlite3_bind_text | bindings] of that [parameter]. 
3609
** ^The specific value of WHERE-clause [parameter] might influence the 
3610
** choice of query plan if the parameter is the left-hand side of a [LIKE]
3611
** or [GLOB] operator or if the parameter is compared to an indexed column
3612
** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
3613
** </li>
3614
** </ol>
3615
**
3616
** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
3617
** the extra prepFlags parameter, which is a bit array consisting of zero or
3618
** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags.  ^The
3619
** sqlite3_prepare_v2() interface works exactly the same as
3620
** sqlite3_prepare_v3() with a zero prepFlags parameter.
3621
*/
3622
SQLITE_API int sqlite3_prepare(
3623
  sqlite3 *db,            /* Database handle */
3624
  const char *zSql,       /* SQL statement, UTF-8 encoded */
3625
  int nByte,              /* Maximum length of zSql in bytes. */
3626
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3627
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
3628
);
3629
SQLITE_API int sqlite3_prepare_v2(
3630
  sqlite3 *db,            /* Database handle */
3631
  const char *zSql,       /* SQL statement, UTF-8 encoded */
3632
  int nByte,              /* Maximum length of zSql in bytes. */
3633
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3634
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
3635
);
3636
SQLITE_API int sqlite3_prepare_v3(
3637
  sqlite3 *db,            /* Database handle */
3638
  const char *zSql,       /* SQL statement, UTF-8 encoded */
3639
  int nByte,              /* Maximum length of zSql in bytes. */
3640
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
3641
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3642
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
3643
);
3644
SQLITE_API int sqlite3_prepare16(
3645
  sqlite3 *db,            /* Database handle */
3646
  const void *zSql,       /* SQL statement, UTF-16 encoded */
3647
  int nByte,              /* Maximum length of zSql in bytes. */
3648
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3649
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
3650
);
3651
SQLITE_API int sqlite3_prepare16_v2(
3652
  sqlite3 *db,            /* Database handle */
3653
  const void *zSql,       /* SQL statement, UTF-16 encoded */
3654
  int nByte,              /* Maximum length of zSql in bytes. */
3655
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3656
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
3657
);
3658
SQLITE_API int sqlite3_prepare16_v3(
3659
  sqlite3 *db,            /* Database handle */
3660
  const void *zSql,       /* SQL statement, UTF-16 encoded */
3661
  int nByte,              /* Maximum length of zSql in bytes. */
3662
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
3663
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
3664
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
3665
);
3666
3667
/*
3668
** CAPI3REF: Retrieving Statement SQL
3669
** METHOD: sqlite3_stmt
3670
**
3671
** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
3672
** SQL text used to create [prepared statement] P if P was
3673
** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
3674
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
3675
** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
3676
** string containing the SQL text of prepared statement P with
3677
** [bound parameters] expanded.
3678
**
3679
** ^(For example, if a prepared statement is created using the SQL
3680
** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
3681
** and parameter :xyz is unbound, then sqlite3_sql() will return
3682
** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
3683
** will return "SELECT 2345,NULL".)^
3684
**
3685
** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
3686
** is available to hold the result, or if the result would exceed the
3687
** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
3688
**
3689
** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
3690
** bound parameter expansions.  ^The [SQLITE_OMIT_TRACE] compile-time
3691
** option causes sqlite3_expanded_sql() to always return NULL.
3692
**
3693
** ^The string returned by sqlite3_sql(P) is managed by SQLite and is
3694
** automatically freed when the prepared statement is finalized.
3695
** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
3696
** is obtained from [sqlite3_malloc()] and must be free by the application
3697
** by passing it to [sqlite3_free()].
3698
*/
3699
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
3700
SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
3701
3702
/*
3703
** CAPI3REF: Determine If An SQL Statement Writes The Database
3704
** METHOD: sqlite3_stmt
3705
**
3706
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
3707
** and only if the [prepared statement] X makes no direct changes to
3708
** the content of the database file.
3709
**
3710
** Note that [application-defined SQL functions] or
3711
** [virtual tables] might change the database indirectly as a side effect.  
3712
** ^(For example, if an application defines a function "eval()" that 
3713
** calls [sqlite3_exec()], then the following SQL statement would
3714
** change the database file through side-effects:
3715
**
3716
** <blockquote><pre>
3717
**    SELECT eval('DELETE FROM t1') FROM t2;
3718
** </pre></blockquote>
3719
**
3720
** But because the [SELECT] statement does not change the database file
3721
** directly, sqlite3_stmt_readonly() would still return true.)^
3722
**
3723
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
3724
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
3725
** since the statements themselves do not actually modify the database but
3726
** rather they control the timing of when other statements modify the 
3727
** database.  ^The [ATTACH] and [DETACH] statements also cause
3728
** sqlite3_stmt_readonly() to return true since, while those statements
3729
** change the configuration of a database connection, they do not make 
3730
** changes to the content of the database files on disk.
3731
** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
3732
** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
3733
** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
3734
** sqlite3_stmt_readonly() returns false for those commands.
3735
*/
3736
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
3737
3738
/*
3739
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
3740
** METHOD: sqlite3_stmt
3741
**
3742
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
3743
** [prepared statement] S has been stepped at least once using 
3744
** [sqlite3_step(S)] but has neither run to completion (returned
3745
** [SQLITE_DONE] from [sqlite3_step(S)]) nor
3746
** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
3747
** interface returns false if S is a NULL pointer.  If S is not a 
3748
** NULL pointer and is not a pointer to a valid [prepared statement]
3749
** object, then the behavior is undefined and probably undesirable.
3750
**
3751
** This interface can be used in combination [sqlite3_next_stmt()]
3752
** to locate all prepared statements associated with a database 
3753
** connection that are in need of being reset.  This can be used,
3754
** for example, in diagnostic routines to search for prepared 
3755
** statements that are holding a transaction open.
3756
*/
3757
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
3758
3759
/*
3760
** CAPI3REF: Dynamically Typed Value Object
3761
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
3762
**
3763
** SQLite uses the sqlite3_value object to represent all values
3764
** that can be stored in a database table. SQLite uses dynamic typing
3765
** for the values it stores.  ^Values stored in sqlite3_value objects
3766
** can be integers, floating point values, strings, BLOBs, or NULL.
3767
**
3768
** An sqlite3_value object may be either "protected" or "unprotected".
3769
** Some interfaces require a protected sqlite3_value.  Other interfaces
3770
** will accept either a protected or an unprotected sqlite3_value.
3771
** Every interface that accepts sqlite3_value arguments specifies
3772
** whether or not it requires a protected sqlite3_value.  The
3773
** [sqlite3_value_dup()] interface can be used to construct a new 
3774
** protected sqlite3_value from an unprotected sqlite3_value.
3775
**
3776
** The terms "protected" and "unprotected" refer to whether or not
3777
** a mutex is held.  An internal mutex is held for a protected
3778
** sqlite3_value object but no mutex is held for an unprotected
3779
** sqlite3_value object.  If SQLite is compiled to be single-threaded
3780
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
3781
** or if SQLite is run in one of reduced mutex modes 
3782
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
3783
** then there is no distinction between protected and unprotected
3784
** sqlite3_value objects and they can be used interchangeably.  However,
3785
** for maximum code portability it is recommended that applications
3786
** still make the distinction between protected and unprotected
3787
** sqlite3_value objects even when not strictly required.
3788
**
3789
** ^The sqlite3_value objects that are passed as parameters into the
3790
** implementation of [application-defined SQL functions] are protected.
3791
** ^The sqlite3_value object returned by
3792
** [sqlite3_column_value()] is unprotected.
3793
** Unprotected sqlite3_value objects may only be used as arguments
3794
** to [sqlite3_result_value()], [sqlite3_bind_value()], and
3795
** [sqlite3_value_dup()].
3796
** The [sqlite3_value_blob | sqlite3_value_type()] family of
3797
** interfaces require protected sqlite3_value objects.
3798
*/
3799
typedef struct sqlite3_value sqlite3_value;
3800
3801
/*
3802
** CAPI3REF: SQL Function Context Object
3803
**
3804
** The context in which an SQL function executes is stored in an
3805
** sqlite3_context object.  ^A pointer to an sqlite3_context object
3806
** is always first parameter to [application-defined SQL functions].
3807
** The application-defined SQL function implementation will pass this
3808
** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
3809
** [sqlite3_aggregate_context()], [sqlite3_user_data()],
3810
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
3811
** and/or [sqlite3_set_auxdata()].
3812
*/
3813
typedef struct sqlite3_context sqlite3_context;
3814
3815
/*
3816
** CAPI3REF: Binding Values To Prepared Statements
3817
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
3818
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
3819
** METHOD: sqlite3_stmt
3820
**
3821
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
3822
** literals may be replaced by a [parameter] that matches one of following
3823
** templates:
3824
**
3825
** <ul>
3826
** <li>  ?
3827
** <li>  ?NNN
3828
** <li>  :VVV
3829
** <li>  @VVV
3830
** <li>  $VVV
3831
** </ul>
3832
**
3833
** In the templates above, NNN represents an integer literal,
3834
** and VVV represents an alphanumeric identifier.)^  ^The values of these
3835
** parameters (also called "host parameter names" or "SQL parameters")
3836
** can be set using the sqlite3_bind_*() routines defined here.
3837
**
3838
** ^The first argument to the sqlite3_bind_*() routines is always
3839
** a pointer to the [sqlite3_stmt] object returned from
3840
** [sqlite3_prepare_v2()] or its variants.
3841
**
3842
** ^The second argument is the index of the SQL parameter to be set.
3843
** ^The leftmost SQL parameter has an index of 1.  ^When the same named
3844
** SQL parameter is used more than once, second and subsequent
3845
** occurrences have the same index as the first occurrence.
3846
** ^The index for named parameters can be looked up using the
3847
** [sqlite3_bind_parameter_index()] API if desired.  ^The index
3848
** for "?NNN" parameters is the value of NNN.
3849
** ^The NNN value must be between 1 and the [sqlite3_limit()]
3850
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
3851
**
3852
** ^The third argument is the value to bind to the parameter.
3853
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3854
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
3855
** is ignored and the end result is the same as sqlite3_bind_null().
3856
**
3857
** ^(In those routines that have a fourth argument, its value is the
3858
** number of bytes in the parameter.  To be clear: the value is the
3859
** number of <u>bytes</u> in the value, not the number of characters.)^
3860
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
3861
** is negative, then the length of the string is
3862
** the number of bytes up to the first zero terminator.
3863
** If the fourth parameter to sqlite3_bind_blob() is negative, then
3864
** the behavior is undefined.
3865
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
3866
** or sqlite3_bind_text16() or sqlite3_bind_text64() then
3867
** that parameter must be the byte offset
3868
** where the NUL terminator would occur assuming the string were NUL
3869
** terminated.  If any NUL characters occur at byte offsets less than 
3870
** the value of the fourth parameter then the resulting string value will
3871
** contain embedded NULs.  The result of expressions involving strings
3872
** with embedded NULs is undefined.
3873
**
3874
** ^The fifth argument to the BLOB and string binding interfaces
3875
** is a destructor used to dispose of the BLOB or
3876
** string after SQLite has finished with it.  ^The destructor is called
3877
** to dispose of the BLOB or string even if the call to bind API fails.
3878
** ^If the fifth argument is
3879
** the special value [SQLITE_STATIC], then SQLite assumes that the
3880
** information is in static, unmanaged space and does not need to be freed.
3881
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
3882
** SQLite makes its own private copy of the data immediately, before
3883
** the sqlite3_bind_*() routine returns.
3884
**
3885
** ^The sixth argument to sqlite3_bind_text64() must be one of
3886
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
3887
** to specify the encoding of the text in the third parameter.  If
3888
** the sixth argument to sqlite3_bind_text64() is not one of the
3889
** allowed values shown above, or if the text encoding is different
3890
** from the encoding specified by the sixth parameter, then the behavior
3891
** is undefined.
3892
**
3893
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
3894
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
3895
** (just an integer to hold its size) while it is being processed.
3896
** Zeroblobs are intended to serve as placeholders for BLOBs whose
3897
** content is later written using
3898
** [sqlite3_blob_open | incremental BLOB I/O] routines.
3899
** ^A negative value for the zeroblob results in a zero-length BLOB.
3900
**
3901
** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
3902
** [prepared statement] S to have an SQL value of NULL, but to also be
3903
** associated with the pointer P of type T.  ^D is either a NULL pointer or
3904
** a pointer to a destructor function for P. ^SQLite will invoke the
3905
** destructor D with a single argument of P when it is finished using
3906
** P.  The T parameter should be a static string, preferably a string
3907
** literal. The sqlite3_bind_pointer() routine is part of the
3908
** [pointer passing interface] added for SQLite 3.20.0.
3909
**
3910
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
3911
** for the [prepared statement] or with a prepared statement for which
3912
** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
3913
** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
3914
** routine is passed a [prepared statement] that has been finalized, the
3915
** result is undefined and probably harmful.
3916
**
3917
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
3918
** ^Unbound parameters are interpreted as NULL.
3919
**
3920
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
3921
** [error code] if anything goes wrong.
3922
** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
3923
** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
3924
** [SQLITE_MAX_LENGTH].
3925
** ^[SQLITE_RANGE] is returned if the parameter
3926
** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
3927
**
3928
** See also: [sqlite3_bind_parameter_count()],
3929
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
3930
*/
3931
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
3932
SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
3933
                        void(*)(void*));
3934
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
3935
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
3936
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
3937
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
3938
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
3939
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
3940
SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
3941
                         void(*)(void*), unsigned char encoding);
3942
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
3943
SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
3944
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
3945
SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
3946
3947
/*
3948
** CAPI3REF: Number Of SQL Parameters
3949
** METHOD: sqlite3_stmt
3950
**
3951
** ^This routine can be used to find the number of [SQL parameters]
3952
** in a [prepared statement].  SQL parameters are tokens of the
3953
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
3954
** placeholders for values that are [sqlite3_bind_blob | bound]
3955
** to the parameters at a later time.
3956
**
3957
** ^(This routine actually returns the index of the largest (rightmost)
3958
** parameter. For all forms except ?NNN, this will correspond to the
3959
** number of unique parameters.  If parameters of the ?NNN form are used,
3960
** there may be gaps in the list.)^
3961
**
3962
** See also: [sqlite3_bind_blob|sqlite3_bind()],
3963
** [sqlite3_bind_parameter_name()], and
3964
** [sqlite3_bind_parameter_index()].
3965
*/
3966
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
3967
3968
/*
3969
** CAPI3REF: Name Of A Host Parameter
3970
** METHOD: sqlite3_stmt
3971
**
3972
** ^The sqlite3_bind_parameter_name(P,N) interface returns
3973
** the name of the N-th [SQL parameter] in the [prepared statement] P.
3974
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
3975
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
3976
** respectively.
3977
** In other words, the initial ":" or "$" or "@" or "?"
3978
** is included as part of the name.)^
3979
** ^Parameters of the form "?" without a following integer have no name
3980
** and are referred to as "nameless" or "anonymous parameters".
3981
**
3982
** ^The first host parameter has an index of 1, not 0.
3983
**
3984
** ^If the value N is out of range or if the N-th parameter is
3985
** nameless, then NULL is returned.  ^The returned string is
3986
** always in UTF-8 encoding even if the named parameter was
3987
** originally specified as UTF-16 in [sqlite3_prepare16()],
3988
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
3989
**
3990
** See also: [sqlite3_bind_blob|sqlite3_bind()],
3991
** [sqlite3_bind_parameter_count()], and
3992
** [sqlite3_bind_parameter_index()].
3993
*/
3994
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
3995
3996
/*
3997
** CAPI3REF: Index Of A Parameter With A Given Name
3998
** METHOD: sqlite3_stmt
3999
**
4000
** ^Return the index of an SQL parameter given its name.  ^The
4001
** index value returned is suitable for use as the second
4002
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
4003
** is returned if no matching parameter is found.  ^The parameter
4004
** name must be given in UTF-8 even if the original statement
4005
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
4006
** [sqlite3_prepare16_v3()].
4007
**
4008
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4009
** [sqlite3_bind_parameter_count()], and
4010
** [sqlite3_bind_parameter_name()].
4011
*/
4012
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
4013
4014
/*
4015
** CAPI3REF: Reset All Bindings On A Prepared Statement
4016
** METHOD: sqlite3_stmt
4017
**
4018
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
4019
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
4020
** ^Use this routine to reset all host parameters to NULL.
4021
*/
4022
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
4023
4024
/*
4025
** CAPI3REF: Number Of Columns In A Result Set
4026
** METHOD: sqlite3_stmt
4027
**
4028
** ^Return the number of columns in the result set returned by the
4029
** [prepared statement]. ^If this routine returns 0, that means the 
4030
** [prepared statement] returns no data (for example an [UPDATE]).
4031
** ^However, just because this routine returns a positive number does not
4032
** mean that one or more rows of data will be returned.  ^A SELECT statement
4033
** will always have a positive sqlite3_column_count() but depending on the
4034
** WHERE clause constraints and the table content, it might return no rows.
4035
**
4036
** See also: [sqlite3_data_count()]
4037
*/
4038
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
4039
4040
/*
4041
** CAPI3REF: Column Names In A Result Set
4042
** METHOD: sqlite3_stmt
4043
**
4044
** ^These routines return the name assigned to a particular column
4045
** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
4046
** interface returns a pointer to a zero-terminated UTF-8 string
4047
** and sqlite3_column_name16() returns a pointer to a zero-terminated
4048
** UTF-16 string.  ^The first parameter is the [prepared statement]
4049
** that implements the [SELECT] statement. ^The second parameter is the
4050
** column number.  ^The leftmost column is number 0.
4051
**
4052
** ^The returned string pointer is valid until either the [prepared statement]
4053
** is destroyed by [sqlite3_finalize()] or until the statement is automatically
4054
** reprepared by the first call to [sqlite3_step()] for a particular run
4055
** or until the next call to
4056
** sqlite3_column_name() or sqlite3_column_name16() on the same column.
4057
**
4058
** ^If sqlite3_malloc() fails during the processing of either routine
4059
** (for example during a conversion from UTF-8 to UTF-16) then a
4060
** NULL pointer is returned.
4061
**
4062
** ^The name of a result column is the value of the "AS" clause for
4063
** that column, if there is an AS clause.  If there is no AS clause
4064
** then the name of the column is unspecified and may change from
4065
** one release of SQLite to the next.
4066
*/
4067
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
4068
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
4069
4070
/*
4071
** CAPI3REF: Source Of Data In A Query Result
4072
** METHOD: sqlite3_stmt
4073
**
4074
** ^These routines provide a means to determine the database, table, and
4075
** table column that is the origin of a particular result column in
4076
** [SELECT] statement.
4077
** ^The name of the database or table or column can be returned as
4078
** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
4079
** the database name, the _table_ routines return the table name, and
4080
** the origin_ routines return the column name.
4081
** ^The returned string is valid until the [prepared statement] is destroyed
4082
** using [sqlite3_finalize()] or until the statement is automatically
4083
** reprepared by the first call to [sqlite3_step()] for a particular run
4084
** or until the same information is requested
4085
** again in a different encoding.
4086
**
4087
** ^The names returned are the original un-aliased names of the
4088
** database, table, and column.
4089
**
4090
** ^The first argument to these interfaces is a [prepared statement].
4091
** ^These functions return information about the Nth result column returned by
4092
** the statement, where N is the second function argument.
4093
** ^The left-most column is column 0 for these routines.
4094
**
4095
** ^If the Nth column returned by the statement is an expression or
4096
** subquery and is not a column value, then all of these functions return
4097
** NULL.  ^These routine might also return NULL if a memory allocation error
4098
** occurs.  ^Otherwise, they return the name of the attached database, table,
4099
** or column that query result column was extracted from.
4100
**
4101
** ^As with all other SQLite APIs, those whose names end with "16" return
4102
** UTF-16 encoded strings and the other functions return UTF-8.
4103
**
4104
** ^These APIs are only available if the library was compiled with the
4105
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
4106
**
4107
** If two or more threads call one or more of these routines against the same
4108
** prepared statement and column at the same time then the results are
4109
** undefined.
4110
**
4111
** If two or more threads call one or more
4112
** [sqlite3_column_database_name | column metadata interfaces]
4113
** for the same [prepared statement] and result column
4114
** at the same time then the results are undefined.
4115
*/
4116
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
4117
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
4118
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
4119
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
4120
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
4121
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
4122
4123
/*
4124
** CAPI3REF: Declared Datatype Of A Query Result
4125
** METHOD: sqlite3_stmt
4126
**
4127
** ^(The first parameter is a [prepared statement].
4128
** If this statement is a [SELECT] statement and the Nth column of the
4129
** returned result set of that [SELECT] is a table column (not an
4130
** expression or subquery) then the declared type of the table
4131
** column is returned.)^  ^If the Nth column of the result set is an
4132
** expression or subquery, then a NULL pointer is returned.
4133
** ^The returned string is always UTF-8 encoded.
4134
**
4135
** ^(For example, given the database schema:
4136
**
4137
** CREATE TABLE t1(c1 VARIANT);
4138
**
4139
** and the following statement to be compiled:
4140
**
4141
** SELECT c1 + 1, c1 FROM t1;
4142
**
4143
** this routine would return the string "VARIANT" for the second result
4144
** column (i==1), and a NULL pointer for the first result column (i==0).)^
4145
**
4146
** ^SQLite uses dynamic run-time typing.  ^So just because a column
4147
** is declared to contain a particular type does not mean that the
4148
** data stored in that column is of the declared type.  SQLite is
4149
** strongly typed, but the typing is dynamic not static.  ^Type
4150
** is associated with individual values, not with the containers
4151
** used to hold those values.
4152
*/
4153
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
4154
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
4155
4156
/*
4157
** CAPI3REF: Evaluate An SQL Statement
4158
** METHOD: sqlite3_stmt
4159
**
4160
** After a [prepared statement] has been prepared using any of
4161
** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
4162
** or [sqlite3_prepare16_v3()] or one of the legacy
4163
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
4164
** must be called one or more times to evaluate the statement.
4165
**
4166
** The details of the behavior of the sqlite3_step() interface depend
4167
** on whether the statement was prepared using the newer "vX" interfaces
4168
** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
4169
** [sqlite3_prepare16_v2()] or the older legacy
4170
** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
4171
** new "vX" interface is recommended for new applications but the legacy
4172
** interface will continue to be supported.
4173
**
4174
** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
4175
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
4176
** ^With the "v2" interface, any of the other [result codes] or
4177
** [extended result codes] might be returned as well.
4178
**
4179
** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
4180
** database locks it needs to do its job.  ^If the statement is a [COMMIT]
4181
** or occurs outside of an explicit transaction, then you can retry the
4182
** statement.  If the statement is not a [COMMIT] and occurs within an
4183
** explicit transaction then you should rollback the transaction before
4184
** continuing.
4185
**
4186
** ^[SQLITE_DONE] means that the statement has finished executing
4187
** successfully.  sqlite3_step() should not be called again on this virtual
4188
** machine without first calling [sqlite3_reset()] to reset the virtual
4189
** machine back to its initial state.
4190
**
4191
** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
4192
** is returned each time a new row of data is ready for processing by the
4193
** caller. The values may be accessed using the [column access functions].
4194
** sqlite3_step() is called again to retrieve the next row of data.
4195
**
4196
** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
4197
** violation) has occurred.  sqlite3_step() should not be called again on
4198
** the VM. More information may be found by calling [sqlite3_errmsg()].
4199
** ^With the legacy interface, a more specific error code (for example,
4200
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
4201
** can be obtained by calling [sqlite3_reset()] on the
4202
** [prepared statement].  ^In the "v2" interface,
4203
** the more specific error code is returned directly by sqlite3_step().
4204
**
4205
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
4206
** Perhaps it was called on a [prepared statement] that has
4207
** already been [sqlite3_finalize | finalized] or on one that had
4208
** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
4209
** be the case that the same database connection is being used by two or
4210
** more threads at the same moment in time.
4211
**
4212
** For all versions of SQLite up to and including 3.6.23.1, a call to
4213
** [sqlite3_reset()] was required after sqlite3_step() returned anything
4214
** other than [SQLITE_ROW] before any subsequent invocation of
4215
** sqlite3_step().  Failure to reset the prepared statement using 
4216
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
4217
** sqlite3_step().  But after [version 3.6.23.1] ([dateof:3.6.23.1],
4218
** sqlite3_step() began
4219
** calling [sqlite3_reset()] automatically in this circumstance rather
4220
** than returning [SQLITE_MISUSE].  This is not considered a compatibility
4221
** break because any application that ever receives an SQLITE_MISUSE error
4222
** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
4223
** can be used to restore the legacy behavior.
4224
**
4225
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
4226
** API always returns a generic error code, [SQLITE_ERROR], following any
4227
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
4228
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
4229
** specific [error codes] that better describes the error.
4230
** We admit that this is a goofy design.  The problem has been fixed
4231
** with the "v2" interface.  If you prepare all of your SQL statements
4232
** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
4233
** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
4234
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
4235
** then the more specific [error codes] are returned directly
4236
** by sqlite3_step().  The use of the "vX" interfaces is recommended.
4237
*/
4238
SQLITE_API int sqlite3_step(sqlite3_stmt*);
4239
4240
/*
4241
** CAPI3REF: Number of columns in a result set
4242
** METHOD: sqlite3_stmt
4243
**
4244
** ^The sqlite3_data_count(P) interface returns the number of columns in the
4245
** current row of the result set of [prepared statement] P.
4246
** ^If prepared statement P does not have results ready to return
4247
** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
4248
** interfaces) then sqlite3_data_count(P) returns 0.
4249
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
4250
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
4251
** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
4252
** will return non-zero if previous call to [sqlite3_step](P) returned
4253
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
4254
** where it always returns zero since each step of that multi-step
4255
** pragma returns 0 columns of data.
4256
**
4257
** See also: [sqlite3_column_count()]
4258
*/
4259
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
4260
4261
/*
4262
** CAPI3REF: Fundamental Datatypes
4263
** KEYWORDS: SQLITE_TEXT
4264
**
4265
** ^(Every value in SQLite has one of five fundamental datatypes:
4266
**
4267
** <ul>
4268
** <li> 64-bit signed integer
4269
** <li> 64-bit IEEE floating point number
4270
** <li> string
4271
** <li> BLOB
4272
** <li> NULL
4273
** </ul>)^
4274
**
4275
** These constants are codes for each of those types.
4276
**
4277
** Note that the SQLITE_TEXT constant was also used in SQLite version 2
4278
** for a completely different meaning.  Software that links against both
4279
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
4280
** SQLITE_TEXT.
4281
*/
4282
#define SQLITE_INTEGER  1
4283
#define SQLITE_FLOAT    2
4284
#define SQLITE_BLOB     4
4285
#define SQLITE_NULL     5
4286
#ifdef SQLITE_TEXT
4287
# undef SQLITE_TEXT
4288
#else
4289
# define SQLITE_TEXT     3
4290
#endif
4291
#define SQLITE3_TEXT     3
4292
4293
/*
4294
** CAPI3REF: Result Values From A Query
4295
** KEYWORDS: {column access functions}
4296
** METHOD: sqlite3_stmt
4297
**
4298
** <b>Summary:</b>
4299
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
4300
** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
4301
** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
4302
** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
4303
** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
4304
** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
4305
** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
4306
** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an 
4307
** [sqlite3_value|unprotected sqlite3_value] object.
4308
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
4309
** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
4310
** or a UTF-8 TEXT result in bytes
4311
** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
4312
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
4313
** TEXT in bytes
4314
** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
4315
** datatype of the result
4316
** </table></blockquote>
4317
**
4318
** <b>Details:</b>
4319
**
4320
** ^These routines return information about a single column of the current
4321
** result row of a query.  ^In every case the first argument is a pointer
4322
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
4323
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
4324
** and the second argument is the index of the column for which information
4325
** should be returned. ^The leftmost column of the result set has the index 0.
4326
** ^The number of columns in the result can be determined using
4327
** [sqlite3_column_count()].
4328
**
4329
** If the SQL statement does not currently point to a valid row, or if the
4330
** column index is out of range, the result is undefined.
4331
** These routines may only be called when the most recent call to
4332
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
4333
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
4334
** If any of these routines are called after [sqlite3_reset()] or
4335
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
4336
** something other than [SQLITE_ROW], the results are undefined.
4337
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
4338
** are called from a different thread while any of these routines
4339
** are pending, then the results are undefined.
4340
**
4341
** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
4342
** each return the value of a result column in a specific data format.  If
4343
** the result column is not initially in the requested format (for example,
4344
** if the query returns an integer but the sqlite3_column_text() interface
4345
** is used to extract the value) then an automatic type conversion is performed.
4346
**
4347
** ^The sqlite3_column_type() routine returns the
4348
** [SQLITE_INTEGER | datatype code] for the initial data type
4349
** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
4350
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
4351
** The return value of sqlite3_column_type() can be used to decide which
4352
** of the first six interface should be used to extract the column value.
4353
** The value returned by sqlite3_column_type() is only meaningful if no
4354
** automatic type conversions have occurred for the value in question.  
4355
** After a type conversion, the result of calling sqlite3_column_type()
4356
** is undefined, though harmless.  Future
4357
** versions of SQLite may change the behavior of sqlite3_column_type()
4358
** following a type conversion.
4359
**
4360
** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
4361
** or sqlite3_column_bytes16() interfaces can be used to determine the size
4362
** of that BLOB or string.
4363
**
4364
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
4365
** routine returns the number of bytes in that BLOB or string.
4366
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
4367
** the string to UTF-8 and then returns the number of bytes.
4368
** ^If the result is a numeric value then sqlite3_column_bytes() uses
4369
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
4370
** the number of bytes in that string.
4371
** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
4372
**
4373
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
4374
** routine returns the number of bytes in that BLOB or string.
4375
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
4376
** the string to UTF-16 and then returns the number of bytes.
4377
** ^If the result is a numeric value then sqlite3_column_bytes16() uses
4378
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
4379
** the number of bytes in that string.
4380
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
4381
**
4382
** ^The values returned by [sqlite3_column_bytes()] and 
4383
** [sqlite3_column_bytes16()] do not include the zero terminators at the end
4384
** of the string.  ^For clarity: the values returned by
4385
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
4386
** bytes in the string, not the number of characters.
4387
**
4388
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
4389
** even empty strings, are always zero-terminated.  ^The return
4390
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
4391
**
4392
** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
4393
** [unprotected sqlite3_value] object.  In a multithreaded environment,
4394
** an unprotected sqlite3_value object may only be used safely with
4395
** [sqlite3_bind_value()] and [sqlite3_result_value()].
4396
** If the [unprotected sqlite3_value] object returned by
4397
** [sqlite3_column_value()] is used in any other way, including calls
4398
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
4399
** or [sqlite3_value_bytes()], the behavior is not threadsafe.
4400
** Hence, the sqlite3_column_value() interface
4401
** is normally only useful within the implementation of 
4402
** [application-defined SQL functions] or [virtual tables], not within
4403
** top-level application code.
4404
**
4405
** The these routines may attempt to convert the datatype of the result.
4406
** ^For example, if the internal representation is FLOAT and a text result
4407
** is requested, [sqlite3_snprintf()] is used internally to perform the
4408
** conversion automatically.  ^(The following table details the conversions
4409
** that are applied:
4410
**
4411
** <blockquote>
4412
** <table border="1">
4413
** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
4414
**
4415
** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
4416
** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
4417
** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
4418
** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
4419
** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
4420
** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
4421
** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
4422
** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
4423
** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
4424
** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
4425
** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
4426
** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
4427
** <tr><td>  TEXT    <td>   BLOB    <td> No change
4428
** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
4429
** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
4430
** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
4431
** </table>
4432
** </blockquote>)^
4433
**
4434
** Note that when type conversions occur, pointers returned by prior
4435
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
4436
** sqlite3_column_text16() may be invalidated.
4437
** Type conversions and pointer invalidations might occur
4438
** in the following cases:
4439
**
4440
** <ul>
4441
** <li> The initial content is a BLOB and sqlite3_column_text() or
4442
**      sqlite3_column_text16() is called.  A zero-terminator might
4443
**      need to be added to the string.</li>
4444
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
4445
**      sqlite3_column_text16() is called.  The content must be converted
4446
**      to UTF-16.</li>
4447
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
4448
**      sqlite3_column_text() is called.  The content must be converted
4449
**      to UTF-8.</li>
4450
** </ul>
4451
**
4452
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
4453
** not invalidate a prior pointer, though of course the content of the buffer
4454
** that the prior pointer references will have been modified.  Other kinds
4455
** of conversion are done in place when it is possible, but sometimes they
4456
** are not possible and in those cases prior pointers are invalidated.
4457
**
4458
** The safest policy is to invoke these routines
4459
** in one of the following ways:
4460
**
4461
** <ul>
4462
**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
4463
**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
4464
**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
4465
** </ul>
4466
**
4467
** In other words, you should call sqlite3_column_text(),
4468
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
4469
** into the desired format, then invoke sqlite3_column_bytes() or
4470
** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
4471
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
4472
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
4473
** with calls to sqlite3_column_bytes().
4474
**
4475
** ^The pointers returned are valid until a type conversion occurs as
4476
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
4477
** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
4478
** and BLOBs is freed automatically.  Do not pass the pointers returned
4479
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
4480
** [sqlite3_free()].
4481
**
4482
** ^(If a memory allocation error occurs during the evaluation of any
4483
** of these routines, a default value is returned.  The default value
4484
** is either the integer 0, the floating point number 0.0, or a NULL
4485
** pointer.  Subsequent calls to [sqlite3_errcode()] will return
4486
** [SQLITE_NOMEM].)^
4487
*/
4488
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
4489
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
4490
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
4491
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
4492
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
4493
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
4494
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
4495
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
4496
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
4497
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
4498
4499
/*
4500
** CAPI3REF: Destroy A Prepared Statement Object
4501
** DESTRUCTOR: sqlite3_stmt
4502
**
4503
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
4504
** ^If the most recent evaluation of the statement encountered no errors
4505
** or if the statement is never been evaluated, then sqlite3_finalize() returns
4506
** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
4507
** sqlite3_finalize(S) returns the appropriate [error code] or
4508
** [extended error code].
4509
**
4510
** ^The sqlite3_finalize(S) routine can be called at any point during
4511
** the life cycle of [prepared statement] S:
4512
** before statement S is ever evaluated, after
4513
** one or more calls to [sqlite3_reset()], or after any call
4514
** to [sqlite3_step()] regardless of whether or not the statement has
4515
** completed execution.
4516
**
4517
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
4518
**
4519
** The application must finalize every [prepared statement] in order to avoid
4520
** resource leaks.  It is a grievous error for the application to try to use
4521
** a prepared statement after it has been finalized.  Any use of a prepared
4522
** statement after it has been finalized can result in undefined and
4523
** undesirable behavior such as segfaults and heap corruption.
4524
*/
4525
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
4526
4527
/*
4528
** CAPI3REF: Reset A Prepared Statement Object
4529
** METHOD: sqlite3_stmt
4530
**
4531
** The sqlite3_reset() function is called to reset a [prepared statement]
4532
** object back to its initial state, ready to be re-executed.
4533
** ^Any SQL statement variables that had values bound to them using
4534
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
4535
** Use [sqlite3_clear_bindings()] to reset the bindings.
4536
**
4537
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
4538
** back to the beginning of its program.
4539
**
4540
** ^If the most recent call to [sqlite3_step(S)] for the
4541
** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
4542
** or if [sqlite3_step(S)] has never before been called on S,
4543
** then [sqlite3_reset(S)] returns [SQLITE_OK].
4544
**
4545
** ^If the most recent call to [sqlite3_step(S)] for the
4546
** [prepared statement] S indicated an error, then
4547
** [sqlite3_reset(S)] returns an appropriate [error code].
4548
**
4549
** ^The [sqlite3_reset(S)] interface does not change the values
4550
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
4551
*/
4552
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
4553
4554
/*
4555
** CAPI3REF: Create Or Redefine SQL Functions
4556
** KEYWORDS: {function creation routines}
4557
** KEYWORDS: {application-defined SQL function}
4558
** KEYWORDS: {application-defined SQL functions}
4559
** METHOD: sqlite3
4560
**
4561
** ^These functions (collectively known as "function creation routines")
4562
** are used to add SQL functions or aggregates or to redefine the behavior
4563
** of existing SQL functions or aggregates.  The only differences between
4564
** these routines are the text encoding expected for
4565
** the second parameter (the name of the function being created)
4566
** and the presence or absence of a destructor callback for
4567
** the application data pointer.
4568
**
4569
** ^The first parameter is the [database connection] to which the SQL
4570
** function is to be added.  ^If an application uses more than one database
4571
** connection then application-defined SQL functions must be added
4572
** to each database connection separately.
4573
**
4574
** ^The second parameter is the name of the SQL function to be created or
4575
** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
4576
** representation, exclusive of the zero-terminator.  ^Note that the name
4577
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.  
4578
** ^Any attempt to create a function with a longer name
4579
** will result in [SQLITE_MISUSE] being returned.
4580
**
4581
** ^The third parameter (nArg)
4582
** is the number of arguments that the SQL function or
4583
** aggregate takes. ^If this parameter is -1, then the SQL function or
4584
** aggregate may take any number of arguments between 0 and the limit
4585
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
4586
** parameter is less than -1 or greater than 127 then the behavior is
4587
** undefined.
4588
**
4589
** ^The fourth parameter, eTextRep, specifies what
4590
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
4591
** its parameters.  The application should set this parameter to
4592
** [SQLITE_UTF16LE] if the function implementation invokes 
4593
** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
4594
** implementation invokes [sqlite3_value_text16be()] on an input, or
4595
** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
4596
** otherwise.  ^The same SQL function may be registered multiple times using
4597
** different preferred text encodings, with different implementations for
4598
** each encoding.
4599
** ^When multiple implementations of the same function are available, SQLite
4600
** will pick the one that involves the least amount of data conversion.
4601
**
4602
** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
4603
** to signal that the function will always return the same result given
4604
** the same inputs within a single SQL statement.  Most SQL functions are
4605
** deterministic.  The built-in [random()] SQL function is an example of a
4606
** function that is not deterministic.  The SQLite query planner is able to
4607
** perform additional optimizations on deterministic functions, so use
4608
** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
4609
**
4610
** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
4611
** function can gain access to this pointer using [sqlite3_user_data()].)^
4612
**
4613
** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
4614
** pointers to C-language functions that implement the SQL function or
4615
** aggregate. ^A scalar SQL function requires an implementation of the xFunc
4616
** callback only; NULL pointers must be passed as the xStep and xFinal
4617
** parameters. ^An aggregate SQL function requires an implementation of xStep
4618
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
4619
** SQL function or aggregate, pass NULL pointers for all three function
4620
** callbacks.
4621
**
4622
** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
4623
** then it is destructor for the application data pointer. 
4624
** The destructor is invoked when the function is deleted, either by being
4625
** overloaded or when the database connection closes.)^
4626
** ^The destructor is also invoked if the call to
4627
** sqlite3_create_function_v2() fails.
4628
** ^When the destructor callback of the tenth parameter is invoked, it
4629
** is passed a single argument which is a copy of the application data 
4630
** pointer which was the fifth parameter to sqlite3_create_function_v2().
4631
**
4632
** ^It is permitted to register multiple implementations of the same
4633
** functions with the same name but with either differing numbers of
4634
** arguments or differing preferred text encodings.  ^SQLite will use
4635
** the implementation that most closely matches the way in which the
4636
** SQL function is used.  ^A function implementation with a non-negative
4637
** nArg parameter is a better match than a function implementation with
4638
** a negative nArg.  ^A function where the preferred text encoding
4639
** matches the database encoding is a better
4640
** match than a function where the encoding is different.  
4641
** ^A function where the encoding difference is between UTF16le and UTF16be
4642
** is a closer match than a function where the encoding difference is
4643
** between UTF8 and UTF16.
4644
**
4645
** ^Built-in functions may be overloaded by new application-defined functions.
4646
**
4647
** ^An application-defined function is permitted to call other
4648
** SQLite interfaces.  However, such calls must not
4649
** close the database connection nor finalize or reset the prepared
4650
** statement in which the function is running.
4651
*/
4652
SQLITE_API int sqlite3_create_function(
4653
  sqlite3 *db,
4654
  const char *zFunctionName,
4655
  int nArg,
4656
  int eTextRep,
4657
  void *pApp,
4658
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4659
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4660
  void (*xFinal)(sqlite3_context*)
4661
);
4662
SQLITE_API int sqlite3_create_function16(
4663
  sqlite3 *db,
4664
  const void *zFunctionName,
4665
  int nArg,
4666
  int eTextRep,
4667
  void *pApp,
4668
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4669
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4670
  void (*xFinal)(sqlite3_context*)
4671
);
4672
SQLITE_API int sqlite3_create_function_v2(
4673
  sqlite3 *db,
4674
  const char *zFunctionName,
4675
  int nArg,
4676
  int eTextRep,
4677
  void *pApp,
4678
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
4679
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
4680
  void (*xFinal)(sqlite3_context*),
4681
  void(*xDestroy)(void*)
4682
);
4683
4684
/*
4685
** CAPI3REF: Text Encodings
4686
**
4687
** These constant define integer codes that represent the various
4688
** text encodings supported by SQLite.
4689
*/
4690
#define SQLITE_UTF8           1    /* IMP: R-37514-35566 */
4691
#define SQLITE_UTF16LE        2    /* IMP: R-03371-37637 */
4692
#define SQLITE_UTF16BE        3    /* IMP: R-51971-34154 */
4693
#define SQLITE_UTF16          4    /* Use native byte order */
4694
#define SQLITE_ANY            5    /* Deprecated */
4695
#define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
4696
4697
/*
4698
** CAPI3REF: Function Flags
4699
**
4700
** These constants may be ORed together with the 
4701
** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
4702
** to [sqlite3_create_function()], [sqlite3_create_function16()], or
4703
** [sqlite3_create_function_v2()].
4704
*/
4705
#define SQLITE_DETERMINISTIC    0x800
4706
4707
/*
4708
** CAPI3REF: Deprecated Functions
4709
** DEPRECATED
4710
**
4711
** These functions are [deprecated].  In order to maintain
4712
** backwards compatibility with older code, these functions continue 
4713
** to be supported.  However, new applications should avoid
4714
** the use of these functions.  To encourage programmers to avoid
4715
** these functions, we will not explain what they do.
4716
*/
4717
#ifndef SQLITE_OMIT_DEPRECATED
4718
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
4719
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
4720
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
4721
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
4722
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
4723
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
4724
                      void*,sqlite3_int64);
4725
#endif
4726
4727
/*
4728
** CAPI3REF: Obtaining SQL Values
4729
** METHOD: sqlite3_value
4730
**
4731
** <b>Summary:</b>
4732
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
4733
** <tr><td><b>sqlite3_value_blob</b><td>&rarr;<td>BLOB value
4734
** <tr><td><b>sqlite3_value_double</b><td>&rarr;<td>REAL value
4735
** <tr><td><b>sqlite3_value_int</b><td>&rarr;<td>32-bit INTEGER value
4736
** <tr><td><b>sqlite3_value_int64</b><td>&rarr;<td>64-bit INTEGER value
4737
** <tr><td><b>sqlite3_value_pointer</b><td>&rarr;<td>Pointer value
4738
** <tr><td><b>sqlite3_value_text</b><td>&rarr;<td>UTF-8 TEXT value
4739
** <tr><td><b>sqlite3_value_text16</b><td>&rarr;<td>UTF-16 TEXT value in
4740
** the native byteorder
4741
** <tr><td><b>sqlite3_value_text16be</b><td>&rarr;<td>UTF-16be TEXT value
4742
** <tr><td><b>sqlite3_value_text16le</b><td>&rarr;<td>UTF-16le TEXT value
4743
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
4744
** <tr><td><b>sqlite3_value_bytes</b><td>&rarr;<td>Size of a BLOB
4745
** or a UTF-8 TEXT in bytes
4746
** <tr><td><b>sqlite3_value_bytes16&nbsp;&nbsp;</b>
4747
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
4748
** TEXT in bytes
4749
** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
4750
** datatype of the value
4751
** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
4752
** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
4753
** <tr><td><b>sqlite3_value_nochange&nbsp;&nbsp;</b>
4754
** <td>&rarr;&nbsp;&nbsp;<td>True if the column is unchanged in an UPDATE
4755
** against a virtual table.
4756
** </table></blockquote>
4757
**
4758
** <b>Details:</b>
4759
**
4760
** These routines extract type, size, and content information from
4761
** [protected sqlite3_value] objects.  Protected sqlite3_value objects
4762
** are used to pass parameter information into implementation of
4763
** [application-defined SQL functions] and [virtual tables].
4764
**
4765
** These routines work only with [protected sqlite3_value] objects.
4766
** Any attempt to use these routines on an [unprotected sqlite3_value]
4767
** is not threadsafe.
4768
**
4769
** ^These routines work just like the corresponding [column access functions]
4770
** except that these routines take a single [protected sqlite3_value] object
4771
** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
4772
**
4773
** ^The sqlite3_value_text16() interface extracts a UTF-16 string
4774
** in the native byte-order of the host machine.  ^The
4775
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
4776
** extract UTF-16 strings as big-endian and little-endian respectively.
4777
**
4778
** ^If [sqlite3_value] object V was initialized 
4779
** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
4780
** and if X and Y are strings that compare equal according to strcmp(X,Y),
4781
** then sqlite3_value_pointer(V,Y) will return the pointer P.  ^Otherwise,
4782
** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() 
4783
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
4784
**
4785
** ^(The sqlite3_value_type(V) interface returns the
4786
** [SQLITE_INTEGER | datatype code] for the initial datatype of the
4787
** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
4788
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
4789
** Other interfaces might change the datatype for an sqlite3_value object.
4790
** For example, if the datatype is initially SQLITE_INTEGER and
4791
** sqlite3_value_text(V) is called to extract a text value for that
4792
** integer, then subsequent calls to sqlite3_value_type(V) might return
4793
** SQLITE_TEXT.  Whether or not a persistent internal datatype conversion
4794
** occurs is undefined and may change from one release of SQLite to the next.
4795
**
4796
** ^(The sqlite3_value_numeric_type() interface attempts to apply
4797
** numeric affinity to the value.  This means that an attempt is
4798
** made to convert the value to an integer or floating point.  If
4799
** such a conversion is possible without loss of information (in other
4800
** words, if the value is a string that looks like a number)
4801
** then the conversion is performed.  Otherwise no conversion occurs.
4802
** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
4803
**
4804
** ^Within the [xUpdate] method of a [virtual table], the
4805
** sqlite3_value_nochange(X) interface returns true if and only if
4806
** the column corresponding to X is unchanged by the UPDATE operation
4807
** that the xUpdate method call was invoked to implement and if
4808
** and the prior [xColumn] method call that was invoked to extracted
4809
** the value for that column returned without setting a result (probably
4810
** because it queried [sqlite3_vtab_nochange()] and found that the column
4811
** was unchanging).  ^Within an [xUpdate] method, any value for which
4812
** sqlite3_value_nochange(X) is true will in all other respects appear
4813
** to be a NULL value.  If sqlite3_value_nochange(X) is invoked anywhere other
4814
** than within an [xUpdate] method call for an UPDATE statement, then
4815
** the return value is arbitrary and meaningless.
4816
**
4817
** Please pay particular attention to the fact that the pointer returned
4818
** from [sqlite3_value_blob()], [sqlite3_value_text()], or
4819
** [sqlite3_value_text16()] can be invalidated by a subsequent call to
4820
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
4821
** or [sqlite3_value_text16()].
4822
**
4823
** These routines must be called from the same thread as
4824
** the SQL function that supplied the [sqlite3_value*] parameters.
4825
*/
4826
SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
4827
SQLITE_API double sqlite3_value_double(sqlite3_value*);
4828
SQLITE_API int sqlite3_value_int(sqlite3_value*);
4829
SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
4830
SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
4831
SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
4832
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
4833
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
4834
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
4835
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
4836
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
4837
SQLITE_API int sqlite3_value_type(sqlite3_value*);
4838
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
4839
SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
4840
4841
/*
4842
** CAPI3REF: Finding The Subtype Of SQL Values
4843
** METHOD: sqlite3_value
4844
**
4845
** The sqlite3_value_subtype(V) function returns the subtype for
4846
** an [application-defined SQL function] argument V.  The subtype
4847
** information can be used to pass a limited amount of context from
4848
** one SQL function to another.  Use the [sqlite3_result_subtype()]
4849
** routine to set the subtype for the return value of an SQL function.
4850
*/
4851
SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
4852
4853
/*
4854
** CAPI3REF: Copy And Free SQL Values
4855
** METHOD: sqlite3_value
4856
**
4857
** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
4858
** object D and returns a pointer to that copy.  ^The [sqlite3_value] returned
4859
** is a [protected sqlite3_value] object even if the input is not.
4860
** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
4861
** memory allocation fails.
4862
**
4863
** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
4864
** previously obtained from [sqlite3_value_dup()].  ^If V is a NULL pointer
4865
** then sqlite3_value_free(V) is a harmless no-op.
4866
*/
4867
SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
4868
SQLITE_API void sqlite3_value_free(sqlite3_value*);
4869
4870
/*
4871
** CAPI3REF: Obtain Aggregate Function Context
4872
** METHOD: sqlite3_context
4873
**
4874
** Implementations of aggregate SQL functions use this
4875
** routine to allocate memory for storing their state.
4876
**
4877
** ^The first time the sqlite3_aggregate_context(C,N) routine is called 
4878
** for a particular aggregate function, SQLite
4879
** allocates N of memory, zeroes out that memory, and returns a pointer
4880
** to the new memory. ^On second and subsequent calls to
4881
** sqlite3_aggregate_context() for the same aggregate function instance,
4882
** the same buffer is returned.  Sqlite3_aggregate_context() is normally
4883
** called once for each invocation of the xStep callback and then one
4884
** last time when the xFinal callback is invoked.  ^(When no rows match
4885
** an aggregate query, the xStep() callback of the aggregate function
4886
** implementation is never called and xFinal() is called exactly once.
4887
** In those cases, sqlite3_aggregate_context() might be called for the
4888
** first time from within xFinal().)^
4889
**
4890
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 
4891
** when first called if N is less than or equal to zero or if a memory
4892
** allocate error occurs.
4893
**
4894
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
4895
** determined by the N parameter on first successful call.  Changing the
4896
** value of N in subsequent call to sqlite3_aggregate_context() within
4897
** the same aggregate function instance will not resize the memory
4898
** allocation.)^  Within the xFinal callback, it is customary to set
4899
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 
4900
** pointless memory allocations occur.
4901
**
4902
** ^SQLite automatically frees the memory allocated by 
4903
** sqlite3_aggregate_context() when the aggregate query concludes.
4904
**
4905
** The first parameter must be a copy of the
4906
** [sqlite3_context | SQL function context] that is the first parameter
4907
** to the xStep or xFinal callback routine that implements the aggregate
4908
** function.
4909
**
4910
** This routine must be called from the same thread in which
4911
** the aggregate SQL function is running.
4912
*/
4913
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
4914
4915
/*
4916
** CAPI3REF: User Data For Functions
4917
** METHOD: sqlite3_context
4918
**
4919
** ^The sqlite3_user_data() interface returns a copy of
4920
** the pointer that was the pUserData parameter (the 5th parameter)
4921
** of the [sqlite3_create_function()]
4922
** and [sqlite3_create_function16()] routines that originally
4923
** registered the application defined function.
4924
**
4925
** This routine must be called from the same thread in which
4926
** the application-defined function is running.
4927
*/
4928
SQLITE_API void *sqlite3_user_data(sqlite3_context*);
4929
4930
/*
4931
** CAPI3REF: Database Connection For Functions
4932
** METHOD: sqlite3_context
4933
**
4934
** ^The sqlite3_context_db_handle() interface returns a copy of
4935
** the pointer to the [database connection] (the 1st parameter)
4936
** of the [sqlite3_create_function()]
4937
** and [sqlite3_create_function16()] routines that originally
4938
** registered the application defined function.
4939
*/
4940
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
4941
4942
/*
4943
** CAPI3REF: Function Auxiliary Data
4944
** METHOD: sqlite3_context
4945
**
4946
** These functions may be used by (non-aggregate) SQL functions to
4947
** associate metadata with argument values. If the same value is passed to
4948
** multiple invocations of the same SQL function during query execution, under
4949
** some circumstances the associated metadata may be preserved.  An example
4950
** of where this might be useful is in a regular-expression matching
4951
** function. The compiled version of the regular expression can be stored as
4952
** metadata associated with the pattern string.  
4953
** Then as long as the pattern string remains the same,
4954
** the compiled regular expression can be reused on multiple
4955
** invocations of the same function.
4956
**
4957
** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata
4958
** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
4959
** value to the application-defined function.  ^N is zero for the left-most
4960
** function argument.  ^If there is no metadata
4961
** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
4962
** returns a NULL pointer.
4963
**
4964
** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
4965
** argument of the application-defined function.  ^Subsequent
4966
** calls to sqlite3_get_auxdata(C,N) return P from the most recent
4967
** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
4968
** NULL if the metadata has been discarded.
4969
** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
4970
** SQLite will invoke the destructor function X with parameter P exactly
4971
** once, when the metadata is discarded.
4972
** SQLite is free to discard the metadata at any time, including: <ul>
4973
** <li> ^(when the corresponding function parameter changes)^, or
4974
** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
4975
**      SQL statement)^, or
4976
** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
4977
**       parameter)^, or
4978
** <li> ^(during the original sqlite3_set_auxdata() call when a memory 
4979
**      allocation error occurs.)^ </ul>
4980
**
4981
** Note the last bullet in particular.  The destructor X in 
4982
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
4983
** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
4984
** should be called near the end of the function implementation and the
4985
** function implementation should not make any use of P after
4986
** sqlite3_set_auxdata() has been called.
4987
**
4988
** ^(In practice, metadata is preserved between function calls for
4989
** function parameters that are compile-time constants, including literal
4990
** values and [parameters] and expressions composed from the same.)^
4991
**
4992
** The value of the N parameter to these interfaces should be non-negative.
4993
** Future enhancements may make use of negative N values to define new
4994
** kinds of function caching behavior.
4995
**
4996
** These routines must be called from the same thread in which
4997
** the SQL function is running.
4998
*/
4999
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
5000
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
5001
5002
5003
/*
5004
** CAPI3REF: Constants Defining Special Destructor Behavior
5005
**
5006
** These are special values for the destructor that is passed in as the
5007
** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
5008
** argument is SQLITE_STATIC, it means that the content pointer is constant
5009
** and will never change.  It does not need to be destroyed.  ^The
5010
** SQLITE_TRANSIENT value means that the content will likely change in
5011
** the near future and that SQLite should make its own private copy of
5012
** the content before returning.
5013
**
5014
** The typedef is necessary to work around problems in certain
5015
** C++ compilers.
5016
*/
5017
typedef void (*sqlite3_destructor_type)(void*);
5018
0
#define SQLITE_STATIC      ((sqlite3_destructor_type)0)
5019
#define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
5020
5021
/*
5022
** CAPI3REF: Setting The Result Of An SQL Function
5023
** METHOD: sqlite3_context
5024
**
5025
** These routines are used by the xFunc or xFinal callbacks that
5026
** implement SQL functions and aggregates.  See
5027
** [sqlite3_create_function()] and [sqlite3_create_function16()]
5028
** for additional information.
5029
**
5030
** These functions work very much like the [parameter binding] family of
5031
** functions used to bind values to host parameters in prepared statements.
5032
** Refer to the [SQL parameter] documentation for additional information.
5033
**
5034
** ^The sqlite3_result_blob() interface sets the result from
5035
** an application-defined function to be the BLOB whose content is pointed
5036
** to by the second parameter and which is N bytes long where N is the
5037
** third parameter.
5038
**
5039
** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
5040
** interfaces set the result of the application-defined function to be
5041
** a BLOB containing all zero bytes and N bytes in size.
5042
**
5043
** ^The sqlite3_result_double() interface sets the result from
5044
** an application-defined function to be a floating point value specified
5045
** by its 2nd argument.
5046
**
5047
** ^The sqlite3_result_error() and sqlite3_result_error16() functions
5048
** cause the implemented SQL function to throw an exception.
5049
** ^SQLite uses the string pointed to by the
5050
** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
5051
** as the text of an error message.  ^SQLite interprets the error
5052
** message string from sqlite3_result_error() as UTF-8. ^SQLite
5053
** interprets the string from sqlite3_result_error16() as UTF-16 in native
5054
** byte order.  ^If the third parameter to sqlite3_result_error()
5055
** or sqlite3_result_error16() is negative then SQLite takes as the error
5056
** message all text up through the first zero character.
5057
** ^If the third parameter to sqlite3_result_error() or
5058
** sqlite3_result_error16() is non-negative then SQLite takes that many
5059
** bytes (not characters) from the 2nd parameter as the error message.
5060
** ^The sqlite3_result_error() and sqlite3_result_error16()
5061
** routines make a private copy of the error message text before
5062
** they return.  Hence, the calling function can deallocate or
5063
** modify the text after they return without harm.
5064
** ^The sqlite3_result_error_code() function changes the error code
5065
** returned by SQLite as a result of an error in a function.  ^By default,
5066
** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
5067
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
5068
**
5069
** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
5070
** error indicating that a string or BLOB is too long to represent.
5071
**
5072
** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
5073
** error indicating that a memory allocation failed.
5074
**
5075
** ^The sqlite3_result_int() interface sets the return value
5076
** of the application-defined function to be the 32-bit signed integer
5077
** value given in the 2nd argument.
5078
** ^The sqlite3_result_int64() interface sets the return value
5079
** of the application-defined function to be the 64-bit signed integer
5080
** value given in the 2nd argument.
5081
**
5082
** ^The sqlite3_result_null() interface sets the return value
5083
** of the application-defined function to be NULL.
5084
**
5085
** ^The sqlite3_result_text(), sqlite3_result_text16(),
5086
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
5087
** set the return value of the application-defined function to be
5088
** a text string which is represented as UTF-8, UTF-16 native byte order,
5089
** UTF-16 little endian, or UTF-16 big endian, respectively.
5090
** ^The sqlite3_result_text64() interface sets the return value of an
5091
** application-defined function to be a text string in an encoding
5092
** specified by the fifth (and last) parameter, which must be one
5093
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
5094
** ^SQLite takes the text result from the application from
5095
** the 2nd parameter of the sqlite3_result_text* interfaces.
5096
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
5097
** is negative, then SQLite takes result text from the 2nd parameter
5098
** through the first zero character.
5099
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
5100
** is non-negative, then as many bytes (not characters) of the text
5101
** pointed to by the 2nd parameter are taken as the application-defined
5102
** function result.  If the 3rd parameter is non-negative, then it
5103
** must be the byte offset into the string where the NUL terminator would
5104
** appear if the string where NUL terminated.  If any NUL characters occur
5105
** in the string at a byte offset that is less than the value of the 3rd
5106
** parameter, then the resulting string will contain embedded NULs and the
5107
** result of expressions operating on strings with embedded NULs is undefined.
5108
** ^If the 4th parameter to the sqlite3_result_text* interfaces
5109
** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
5110
** function as the destructor on the text or BLOB result when it has
5111
** finished using that result.
5112
** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
5113
** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
5114
** assumes that the text or BLOB result is in constant space and does not
5115
** copy the content of the parameter nor call a destructor on the content
5116
** when it has finished using that result.
5117
** ^If the 4th parameter to the sqlite3_result_text* interfaces
5118
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
5119
** then SQLite makes a copy of the result into space obtained
5120
** from [sqlite3_malloc()] before it returns.
5121
**
5122
** ^The sqlite3_result_value() interface sets the result of
5123
** the application-defined function to be a copy of the
5124
** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
5125
** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
5126
** so that the [sqlite3_value] specified in the parameter may change or
5127
** be deallocated after sqlite3_result_value() returns without harm.
5128
** ^A [protected sqlite3_value] object may always be used where an
5129
** [unprotected sqlite3_value] object is required, so either
5130
** kind of [sqlite3_value] object can be used with this interface.
5131
**
5132
** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
5133
** SQL NULL value, just like [sqlite3_result_null(C)], except that it
5134
** also associates the host-language pointer P or type T with that 
5135
** NULL value such that the pointer can be retrieved within an
5136
** [application-defined SQL function] using [sqlite3_value_pointer()].
5137
** ^If the D parameter is not NULL, then it is a pointer to a destructor
5138
** for the P parameter.  ^SQLite invokes D with P as its only argument
5139
** when SQLite is finished with P.  The T parameter should be a static
5140
** string and preferably a string literal. The sqlite3_result_pointer()
5141
** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
5142
**
5143
** If these routines are called from within the different thread
5144
** than the one containing the application-defined function that received
5145
** the [sqlite3_context] pointer, the results are undefined.
5146
*/
5147
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
5148
SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
5149
                           sqlite3_uint64,void(*)(void*));
5150
SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
5151
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
5152
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
5153
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
5154
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
5155
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
5156
SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
5157
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
5158
SQLITE_API void sqlite3_result_null(sqlite3_context*);
5159
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
5160
SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
5161
                           void(*)(void*), unsigned char encoding);
5162
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
5163
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
5164
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
5165
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
5166
SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
5167
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
5168
SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
5169
5170
5171
/*
5172
** CAPI3REF: Setting The Subtype Of An SQL Function
5173
** METHOD: sqlite3_context
5174
**
5175
** The sqlite3_result_subtype(C,T) function causes the subtype of
5176
** the result from the [application-defined SQL function] with 
5177
** [sqlite3_context] C to be the value T.  Only the lower 8 bits 
5178
** of the subtype T are preserved in current versions of SQLite;
5179
** higher order bits are discarded.
5180
** The number of subtype bytes preserved by SQLite might increase
5181
** in future releases of SQLite.
5182
*/
5183
SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
5184
5185
/*
5186
** CAPI3REF: Define New Collating Sequences
5187
** METHOD: sqlite3
5188
**
5189
** ^These functions add, remove, or modify a [collation] associated
5190
** with the [database connection] specified as the first argument.
5191
**
5192
** ^The name of the collation is a UTF-8 string
5193
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
5194
** and a UTF-16 string in native byte order for sqlite3_create_collation16().
5195
** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
5196
** considered to be the same name.
5197
**
5198
** ^(The third argument (eTextRep) must be one of the constants:
5199
** <ul>
5200
** <li> [SQLITE_UTF8],
5201
** <li> [SQLITE_UTF16LE],
5202
** <li> [SQLITE_UTF16BE],
5203
** <li> [SQLITE_UTF16], or
5204
** <li> [SQLITE_UTF16_ALIGNED].
5205
** </ul>)^
5206
** ^The eTextRep argument determines the encoding of strings passed
5207
** to the collating function callback, xCallback.
5208
** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
5209
** force strings to be UTF16 with native byte order.