Coverage Report

Created: 2024-08-18 16:21

/home/liu/actions-runner/_work/ccv/ccv/lib/3rdparty/sqlite3/sqlite3.h
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/*
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** 2001-09-15
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**
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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
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** 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
16
** notice, and should not be referenced by programs that use SQLite.
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**
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** Some of the definitions that are in this file are marked as
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** "experimental".  Experimental interfaces are normally new
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** 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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**
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** 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
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** the version number) and changes its name to "sqlite3.h" as
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** part of the build process.
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*/
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#ifndef SQLITE3_H
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#define SQLITE3_H
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#include <stdarg.h>     /* Needed for the definition of va_list */
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37
/*
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** Make sure we can call this stuff from C++.
39
*/
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#ifdef __cplusplus
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extern "C" {
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#endif
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44
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/*
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** Facilitate override of interface linkage and calling conventions.
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** Be aware that these macros may not be used within this particular
48
** translation of the amalgamation and its associated header file.
49
**
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** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the
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** compiler that the target identifier should have external linkage.
52
**
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** The SQLITE_CDECL macro is used to set the calling convention for
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** public functions that accept a variable number of arguments.
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**
56
** The SQLITE_APICALL macro is used to set the calling convention for
57
** public functions that accept a fixed number of arguments.
58
**
59
** The SQLITE_STDCALL macro is no longer used and is now deprecated.
60
**
61
** The SQLITE_CALLBACK macro is used to set the calling convention for
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** function pointers.
63
**
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** The SQLITE_SYSAPI macro is used to set the calling convention for
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** functions provided by the operating system.
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**
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** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and
68
** SQLITE_SYSAPI macros are used only when building for environments
69
** that require non-default calling conventions.
70
*/
71
#ifndef SQLITE_EXTERN
72
# define SQLITE_EXTERN extern
73
#endif
74
#ifndef SQLITE_API
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# define SQLITE_API
76
#endif
77
#ifndef SQLITE_CDECL
78
# define SQLITE_CDECL
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#endif
80
#ifndef SQLITE_APICALL
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# define SQLITE_APICALL
82
#endif
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#ifndef SQLITE_STDCALL
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# define SQLITE_STDCALL SQLITE_APICALL
85
#endif
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#ifndef SQLITE_CALLBACK
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# define SQLITE_CALLBACK
88
#endif
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#ifndef SQLITE_SYSAPI
90
# define SQLITE_SYSAPI
91
#endif
92
93
/*
94
** These no-op macros are used in front of interfaces to mark those
95
** interfaces as either deprecated or experimental.  New applications
96
** should not use deprecated interfaces - they are supported for backwards
97
** compatibility only.  Application writers should be aware that
98
** experimental interfaces are subject to change in point releases.
99
**
100
** These macros used to resolve to various kinds of compiler magic that
101
** would generate warning messages when they were used.  But that
102
** compiler magic ended up generating such a flurry of bug reports
103
** that we have taken it all out and gone back to using simple
104
** noop macros.
105
*/
106
#define SQLITE_DEPRECATED
107
#define SQLITE_EXPERIMENTAL
108
109
/*
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** Ensure these symbols were not defined by some previous header file.
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*/
112
#ifdef SQLITE_VERSION
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# undef SQLITE_VERSION
114
#endif
115
#ifdef SQLITE_VERSION_NUMBER
116
# undef SQLITE_VERSION_NUMBER
117
#endif
118
119
/*
120
** CAPI3REF: Compile-Time Library Version Numbers
121
**
122
** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
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** evaluates to a string literal that is the SQLite version in the
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** format "X.Y.Z" where X is the major version number (always 3 for
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** SQLite3) and Y is the minor version number and Z is the release number.)^
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** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
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** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
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** numbers used in [SQLITE_VERSION].)^
129
** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
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** be larger than the release from which it is derived.  Either Y will
131
** be held constant and Z will be incremented or else Y will be incremented
132
** and Z will be reset to zero.
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**
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** Since [version 3.6.18] ([dateof:3.6.18]),
135
** SQLite source code has been stored in the
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** <a href="http://www.fossil-scm.org/">Fossil configuration management
137
** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
138
** a string which identifies a particular check-in of SQLite
139
** within its configuration management system.  ^The SQLITE_SOURCE_ID
140
** string contains the date and time of the check-in (UTC) and a SHA1
141
** or SHA3-256 hash of the entire source tree.  If the source code has
142
** been edited in any way since it was last checked in, then the last
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** four hexadecimal digits of the hash may be modified.
144
**
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** See also: [sqlite3_libversion()],
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** [sqlite3_libversion_number()], [sqlite3_sourceid()],
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** [sqlite_version()] and [sqlite_source_id()].
148
*/
149
#define SQLITE_VERSION        "3.39.2"
150
#define SQLITE_VERSION_NUMBER 3039002
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#define SQLITE_SOURCE_ID      "2022-07-21 15:24:47 698edb77537b67c41adc68f9b892db56bcf9a55e00371a61420f3ddd668e6603"
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/*
154
** CAPI3REF: Run-Time Library Version Numbers
155
** KEYWORDS: sqlite3_version sqlite3_sourceid
156
**
157
** These interfaces provide the same information as the [SQLITE_VERSION],
158
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
159
** but are associated with the library instead of the header file.  ^(Cautious
160
** programmers might include assert() statements in their application to
161
** verify that values returned by these interfaces match the macros in
162
** the header, and thus ensure that the application is
163
** compiled with matching library and header files.
164
**
165
** <blockquote><pre>
166
** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
167
** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
168
** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
169
** </pre></blockquote>)^
170
**
171
** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
172
** macro.  ^The sqlite3_libversion() function returns a pointer to the
173
** to the sqlite3_version[] string constant.  The sqlite3_libversion()
174
** function is provided for use in DLLs since DLL users usually do not have
175
** direct access to string constants within the DLL.  ^The
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** sqlite3_libversion_number() function returns an integer equal to
177
** [SQLITE_VERSION_NUMBER].  ^(The sqlite3_sourceid() function returns
178
** a pointer to a string constant whose value is the same as the
179
** [SQLITE_SOURCE_ID] C preprocessor macro.  Except if SQLite is built
180
** using an edited copy of [the amalgamation], then the last four characters
181
** of the hash might be different from [SQLITE_SOURCE_ID].)^
182
**
183
** See also: [sqlite_version()] and [sqlite_source_id()].
184
*/
185
SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
186
SQLITE_API const char *sqlite3_libversion(void);
187
SQLITE_API const char *sqlite3_sourceid(void);
188
SQLITE_API int sqlite3_libversion_number(void);
189
190
/*
191
** CAPI3REF: Run-Time Library Compilation Options Diagnostics
192
**
193
** ^The sqlite3_compileoption_used() function returns 0 or 1
194
** indicating whether the specified option was defined at
195
** compile time.  ^The SQLITE_ prefix may be omitted from the
196
** option name passed to sqlite3_compileoption_used().
197
**
198
** ^The sqlite3_compileoption_get() function allows iterating
199
** over the list of options that were defined at compile time by
200
** returning the N-th compile time option string.  ^If N is out of range,
201
** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_
202
** prefix is omitted from any strings returned by
203
** sqlite3_compileoption_get().
204
**
205
** ^Support for the diagnostic functions sqlite3_compileoption_used()
206
** and sqlite3_compileoption_get() may be omitted by specifying the
207
** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
208
**
209
** See also: SQL functions [sqlite_compileoption_used()] and
210
** [sqlite_compileoption_get()] and the [compile_options pragma].
211
*/
212
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
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SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
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SQLITE_API const char *sqlite3_compileoption_get(int N);
215
#else
216
# define sqlite3_compileoption_used(X) 0
217
# define sqlite3_compileoption_get(X)  ((void*)0)
218
#endif
219
220
/*
221
** CAPI3REF: Test To See If The Library Is Threadsafe
222
**
223
** ^The sqlite3_threadsafe() function returns zero if and only if
224
** SQLite was compiled with mutexing code omitted due to the
225
** [SQLITE_THREADSAFE] compile-time option being set to 0.
226
**
227
** SQLite can be compiled with or without mutexes.  When
228
** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
229
** are enabled and SQLite is threadsafe.  When the
230
** [SQLITE_THREADSAFE] macro is 0,
231
** the mutexes are omitted.  Without the mutexes, it is not safe
232
** to use SQLite concurrently from more than one thread.
233
**
234
** Enabling mutexes incurs a measurable performance penalty.
235
** So if speed is of utmost importance, it makes sense to disable
236
** the mutexes.  But for maximum safety, mutexes should be enabled.
237
** ^The default behavior is for mutexes to be enabled.
238
**
239
** This interface can be used by an application to make sure that the
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** version of SQLite that it is linking against was compiled with
241
** the desired setting of the [SQLITE_THREADSAFE] macro.
242
**
243
** This interface only reports on the compile-time mutex setting
244
** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
245
** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
246
** can be fully or partially disabled using a call to [sqlite3_config()]
247
** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
248
** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
249
** sqlite3_threadsafe() function shows only the compile-time setting of
250
** thread safety, not any run-time changes to that setting made by
251
** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
252
** is unchanged by calls to sqlite3_config().)^
253
**
254
** See the [threading mode] documentation for additional information.
255
*/
256
SQLITE_API int sqlite3_threadsafe(void);
257
258
/*
259
** CAPI3REF: Database Connection Handle
260
** KEYWORDS: {database connection} {database connections}
261
**
262
** Each open SQLite database is represented by a pointer to an instance of
263
** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
264
** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
265
** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
266
** and [sqlite3_close_v2()] are its destructors.  There are many other
267
** interfaces (such as
268
** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
269
** [sqlite3_busy_timeout()] to name but three) that are methods on an
270
** sqlite3 object.
271
*/
272
typedef struct sqlite3 sqlite3;
273
274
/*
275
** CAPI3REF: 64-Bit Integer Types
276
** KEYWORDS: sqlite_int64 sqlite_uint64
277
**
278
** Because there is no cross-platform way to specify 64-bit integer types
279
** SQLite includes typedefs for 64-bit signed and unsigned integers.
280
**
281
** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
282
** The sqlite_int64 and sqlite_uint64 types are supported for backwards
283
** compatibility only.
284
**
285
** ^The sqlite3_int64 and sqlite_int64 types can store integer values
286
** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
287
** sqlite3_uint64 and sqlite_uint64 types can store integer values
288
** between 0 and +18446744073709551615 inclusive.
289
*/
290
#ifdef SQLITE_INT64_TYPE
291
  typedef SQLITE_INT64_TYPE sqlite_int64;
292
# ifdef SQLITE_UINT64_TYPE
293
    typedef SQLITE_UINT64_TYPE sqlite_uint64;
294
# else
295
    typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
296
# endif
297
#elif defined(_MSC_VER) || defined(__BORLANDC__)
298
  typedef __int64 sqlite_int64;
299
  typedef unsigned __int64 sqlite_uint64;
300
#else
301
  typedef long long int sqlite_int64;
302
  typedef unsigned long long int sqlite_uint64;
303
#endif
304
typedef sqlite_int64 sqlite3_int64;
305
typedef sqlite_uint64 sqlite3_uint64;
306
307
/*
308
** If compiling for a processor that lacks floating point support,
309
** substitute integer for floating-point.
310
*/
311
#ifdef SQLITE_OMIT_FLOATING_POINT
312
# define double sqlite3_int64
313
#endif
314
315
/*
316
** CAPI3REF: Closing A Database Connection
317
** DESTRUCTOR: sqlite3
318
**
319
** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
320
** for the [sqlite3] object.
321
** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
322
** the [sqlite3] object is successfully destroyed and all associated
323
** resources are deallocated.
324
**
325
** Ideally, applications should [sqlite3_finalize | finalize] all
326
** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and
327
** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
328
** with the [sqlite3] object prior to attempting to close the object.
329
** ^If the database connection is associated with unfinalized prepared
330
** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
331
** sqlite3_close() will leave the database connection open and return
332
** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
333
** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
334
** it returns [SQLITE_OK] regardless, but instead of deallocating the database
335
** connection immediately, it marks the database connection as an unusable
336
** "zombie" and makes arrangements to automatically deallocate the database
337
** connection after all prepared statements are finalized, all BLOB handles
338
** are closed, and all backups have finished. The sqlite3_close_v2() interface
339
** is intended for use with host languages that are garbage collected, and
340
** where the order in which destructors are called is arbitrary.
341
**
342
** ^If an [sqlite3] object is destroyed while a transaction is open,
343
** the transaction is automatically rolled back.
344
**
345
** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
346
** must be either a NULL
347
** pointer or an [sqlite3] object pointer obtained
348
** from [sqlite3_open()], [sqlite3_open16()], or
349
** [sqlite3_open_v2()], and not previously closed.
350
** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
351
** argument is a harmless no-op.
352
*/
353
SQLITE_API int sqlite3_close(sqlite3*);
354
SQLITE_API int sqlite3_close_v2(sqlite3*);
355
356
/*
357
** The type for a callback function.
358
** This is legacy and deprecated.  It is included for historical
359
** compatibility and is not documented.
360
*/
361
typedef int (*sqlite3_callback)(void*,int,char**, char**);
362
363
/*
364
** CAPI3REF: One-Step Query Execution Interface
365
** METHOD: sqlite3
366
**
367
** The sqlite3_exec() interface is a convenience wrapper around
368
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
369
** that allows an application to run multiple statements of SQL
370
** without having to use a lot of C code.
371
**
372
** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
373
** semicolon-separate SQL statements passed into its 2nd argument,
374
** in the context of the [database connection] passed in as its 1st
375
** argument.  ^If the callback function of the 3rd argument to
376
** sqlite3_exec() is not NULL, then it is invoked for each result row
377
** coming out of the evaluated SQL statements.  ^The 4th argument to
378
** sqlite3_exec() is relayed through to the 1st argument of each
379
** callback invocation.  ^If the callback pointer to sqlite3_exec()
380
** is NULL, then no callback is ever invoked and result rows are
381
** ignored.
382
**
383
** ^If an error occurs while evaluating the SQL statements passed into
384
** sqlite3_exec(), then execution of the current statement stops and
385
** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
386
** is not NULL then any error message is written into memory obtained
387
** from [sqlite3_malloc()] and passed back through the 5th parameter.
388
** To avoid memory leaks, the application should invoke [sqlite3_free()]
389
** on error message strings returned through the 5th parameter of
390
** sqlite3_exec() after the error message string is no longer needed.
391
** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
392
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
393
** NULL before returning.
394
**
395
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
396
** routine returns SQLITE_ABORT without invoking the callback again and
397
** without running any subsequent SQL statements.
398
**
399
** ^The 2nd argument to the sqlite3_exec() callback function is the
400
** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
401
** callback is an array of pointers to strings obtained as if from
402
** [sqlite3_column_text()], one for each column.  ^If an element of a
403
** result row is NULL then the corresponding string pointer for the
404
** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
405
** sqlite3_exec() callback is an array of pointers to strings where each
406
** entry represents the name of corresponding result column as obtained
407
** from [sqlite3_column_name()].
408
**
409
** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
410
** to an empty string, or a pointer that contains only whitespace and/or
411
** SQL comments, then no SQL statements are evaluated and the database
412
** is not changed.
413
**
414
** Restrictions:
415
**
416
** <ul>
417
** <li> The application must ensure that the 1st parameter to sqlite3_exec()
418
**      is a valid and open [database connection].
419
** <li> The application must not close the [database connection] specified by
420
**      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
421
** <li> The application must not modify the SQL statement text passed into
422
**      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
423
** </ul>
424
*/
425
SQLITE_API int sqlite3_exec(
426
  sqlite3*,                                  /* An open database */
427
  const char *sql,                           /* SQL to be evaluated */
428
  int (*callback)(void*,int,char**,char**),  /* Callback function */
429
  void *,                                    /* 1st argument to callback */
430
  char **errmsg                              /* Error msg written here */
431
);
432
433
/*
434
** CAPI3REF: Result Codes
435
** KEYWORDS: {result code definitions}
436
**
437
** Many SQLite functions return an integer result code from the set shown
438
** here in order to indicate success or failure.
439
**
440
** New error codes may be added in future versions of SQLite.
441
**
442
** See also: [extended result code definitions]
443
*/
444
50
#define SQLITE_OK           0   /* Successful result */
445
/* beginning-of-error-codes */
446
#define SQLITE_ERROR        1   /* Generic error */
447
#define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
448
#define SQLITE_PERM         3   /* Access permission denied */
449
#define SQLITE_ABORT        4   /* Callback routine requested an abort */
450
#define SQLITE_BUSY         5   /* The database file is locked */
451
#define SQLITE_LOCKED       6   /* A table in the database is locked */
452
#define SQLITE_NOMEM        7   /* A malloc() failed */
453
#define SQLITE_READONLY     8   /* Attempt to write a readonly database */
454
#define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
455
#define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
456
#define SQLITE_CORRUPT     11   /* The database disk image is malformed */
457
#define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
458
#define SQLITE_FULL        13   /* Insertion failed because database is full */
459
#define SQLITE_CANTOPEN    14   /* Unable to open the database file */
460
#define SQLITE_PROTOCOL    15   /* Database lock protocol error */
461
#define SQLITE_EMPTY       16   /* Internal use only */
462
#define SQLITE_SCHEMA      17   /* The database schema changed */
463
#define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
464
#define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
465
#define SQLITE_MISMATCH    20   /* Data type mismatch */
466
#define SQLITE_MISUSE      21   /* Library used incorrectly */
467
#define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
468
#define SQLITE_AUTH        23   /* Authorization denied */
469
#define SQLITE_FORMAT      24   /* Not used */
470
#define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
471
#define SQLITE_NOTADB      26   /* File opened that is not a database file */
472
#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
473
#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
474
134
#define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
475
#define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
476
/* end-of-error-codes */
477
478
/*
479
** CAPI3REF: Extended Result Codes
480
** KEYWORDS: {extended result code definitions}
481
**
482
** In its default configuration, SQLite API routines return one of 30 integer
483
** [result codes].  However, experience has shown that many of
484
** these result codes are too coarse-grained.  They do not provide as
485
** much information about problems as programmers might like.  In an effort to
486
** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
487
** and later) include
488
** support for additional result codes that provide more detailed information
489
** about errors. These [extended result codes] are enabled or disabled
490
** on a per database connection basis using the
491
** [sqlite3_extended_result_codes()] API.  Or, the extended code for
492
** the most recent error can be obtained using
493
** [sqlite3_extended_errcode()].
494
*/
495
#define SQLITE_ERROR_MISSING_COLLSEQ   (SQLITE_ERROR | (1<<8))
496
#define SQLITE_ERROR_RETRY             (SQLITE_ERROR | (2<<8))
497
#define SQLITE_ERROR_SNAPSHOT          (SQLITE_ERROR | (3<<8))
498
#define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
499
#define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
500
#define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
501
#define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
502
#define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
503
#define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
504
#define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
505
#define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
506
#define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
507
#define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
508
#define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
509
#define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
510
#define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
511
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
512
#define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
513
#define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
514
#define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
515
#define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
516
#define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
517
#define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
518
#define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
519
#define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
520
#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
521
#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
522
#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
523
#define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
524
#define SQLITE_IOERR_VNODE             (SQLITE_IOERR | (27<<8))
525
#define SQLITE_IOERR_AUTH              (SQLITE_IOERR | (28<<8))
526
#define SQLITE_IOERR_BEGIN_ATOMIC      (SQLITE_IOERR | (29<<8))
527
#define SQLITE_IOERR_COMMIT_ATOMIC     (SQLITE_IOERR | (30<<8))
528
#define SQLITE_IOERR_ROLLBACK_ATOMIC   (SQLITE_IOERR | (31<<8))
529
#define SQLITE_IOERR_DATA              (SQLITE_IOERR | (32<<8))
530
#define SQLITE_IOERR_CORRUPTFS         (SQLITE_IOERR | (33<<8))
531
#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
532
#define SQLITE_LOCKED_VTAB             (SQLITE_LOCKED |  (2<<8))
533
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
534
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
535
#define SQLITE_BUSY_TIMEOUT            (SQLITE_BUSY   |  (3<<8))
536
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
537
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
538
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
539
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
540
#define SQLITE_CANTOPEN_DIRTYWAL       (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
541
#define SQLITE_CANTOPEN_SYMLINK        (SQLITE_CANTOPEN | (6<<8))
542
#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
543
#define SQLITE_CORRUPT_SEQUENCE        (SQLITE_CORRUPT | (2<<8))
544
#define SQLITE_CORRUPT_INDEX           (SQLITE_CORRUPT | (3<<8))
545
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
546
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
547
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
548
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
549
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
550
#define SQLITE_READONLY_DIRECTORY      (SQLITE_READONLY | (6<<8))
551
#define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
552
#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
553
#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
554
#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
555
#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
556
#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
557
#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
558
#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
559
#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
560
#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
561
#define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
562
#define SQLITE_CONSTRAINT_PINNED       (SQLITE_CONSTRAINT |(11<<8))
563
#define SQLITE_CONSTRAINT_DATATYPE     (SQLITE_CONSTRAINT |(12<<8))
564
#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
565
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
566
#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
567
#define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
568
#define SQLITE_OK_LOAD_PERMANENTLY     (SQLITE_OK | (1<<8))
569
#define SQLITE_OK_SYMLINK              (SQLITE_OK | (2<<8)) /* internal use only */
570
571
/*
572
** CAPI3REF: Flags For File Open Operations
573
**
574
** These bit values are intended for use in the
575
** 3rd parameter to the [sqlite3_open_v2()] interface and
576
** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
577
**
578
** Only those flags marked as "Ok for sqlite3_open_v2()" may be
579
** used as the third argument to the [sqlite3_open_v2()] interface.
580
** The other flags have historically been ignored by sqlite3_open_v2(),
581
** though future versions of SQLite might change so that an error is
582
** raised if any of the disallowed bits are passed into sqlite3_open_v2().
583
** Applications should not depend on the historical behavior.
584
**
585
** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into
586
** [sqlite3_open_v2()] does *not* cause the underlying database file
587
** to be opened using O_EXCL.  Passing SQLITE_OPEN_EXCLUSIVE into
588
** [sqlite3_open_v2()] has historically be a no-op and might become an
589
** error in future versions of SQLite.
590
*/
591
#define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
592
#define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
593
#define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
594
#define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
595
#define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
596
#define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
597
#define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
598
#define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
599
#define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
600
#define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
601
#define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
602
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
603
#define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
604
#define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
605
#define SQLITE_OPEN_SUPER_JOURNAL    0x00004000  /* VFS only */
606
#define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
607
#define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
608
#define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
609
#define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
610
#define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
611
#define SQLITE_OPEN_NOFOLLOW         0x01000000  /* Ok for sqlite3_open_v2() */
612
#define SQLITE_OPEN_EXRESCODE        0x02000000  /* Extended result codes */
613
614
/* Reserved:                         0x00F00000 */
615
/* Legacy compatibility: */
616
#define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
617
618
619
/*
620
** CAPI3REF: Device Characteristics
621
**
622
** The xDeviceCharacteristics method of the [sqlite3_io_methods]
623
** object returns an integer which is a vector of these
624
** bit values expressing I/O characteristics of the mass storage
625
** device that holds the file that the [sqlite3_io_methods]
626
** refers to.
627
**
628
** The SQLITE_IOCAP_ATOMIC property means that all writes of
629
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
630
** mean that writes of blocks that are nnn bytes in size and
631
** are aligned to an address which is an integer multiple of
632
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
633
** that when data is appended to a file, the data is appended
634
** first then the size of the file is extended, never the other
635
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
636
** information is written to disk in the same order as calls
637
** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
638
** after reboot following a crash or power loss, the only bytes in a
639
** file that were written at the application level might have changed
640
** and that adjacent bytes, even bytes within the same sector are
641
** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
642
** flag indicates that a file cannot be deleted when open.  The
643
** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
644
** read-only media and cannot be changed even by processes with
645
** elevated privileges.
646
**
647
** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
648
** filesystem supports doing multiple write operations atomically when those
649
** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
650
** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
651
*/
652
#define SQLITE_IOCAP_ATOMIC                 0x00000001
653
#define SQLITE_IOCAP_ATOMIC512              0x00000002
654
#define SQLITE_IOCAP_ATOMIC1K               0x00000004
655
#define SQLITE_IOCAP_ATOMIC2K               0x00000008
656
#define SQLITE_IOCAP_ATOMIC4K               0x00000010
657
#define SQLITE_IOCAP_ATOMIC8K               0x00000020
658
#define SQLITE_IOCAP_ATOMIC16K              0x00000040
659
#define SQLITE_IOCAP_ATOMIC32K              0x00000080
660
#define SQLITE_IOCAP_ATOMIC64K              0x00000100
661
#define SQLITE_IOCAP_SAFE_APPEND            0x00000200
662
#define SQLITE_IOCAP_SEQUENTIAL             0x00000400
663
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
664
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
665
#define SQLITE_IOCAP_IMMUTABLE              0x00002000
666
#define SQLITE_IOCAP_BATCH_ATOMIC           0x00004000
667
668
/*
669
** CAPI3REF: File Locking Levels
670
**
671
** SQLite uses one of these integer values as the second
672
** argument to calls it makes to the xLock() and xUnlock() methods
673
** of an [sqlite3_io_methods] object.
674
*/
675
#define SQLITE_LOCK_NONE          0
676
#define SQLITE_LOCK_SHARED        1
677
#define SQLITE_LOCK_RESERVED      2
678
#define SQLITE_LOCK_PENDING       3
679
#define SQLITE_LOCK_EXCLUSIVE     4
680
681
/*
682
** CAPI3REF: Synchronization Type Flags
683
**
684
** When SQLite invokes the xSync() method of an
685
** [sqlite3_io_methods] object it uses a combination of
686
** these integer values as the second argument.
687
**
688
** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
689
** sync operation only needs to flush data to mass storage.  Inode
690
** information need not be flushed. If the lower four bits of the flag
691
** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
692
** If the lower four bits equal SQLITE_SYNC_FULL, that means
693
** to use Mac OS X style fullsync instead of fsync().
694
**
695
** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
696
** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
697
** settings.  The [synchronous pragma] determines when calls to the
698
** xSync VFS method occur and applies uniformly across all platforms.
699
** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
700
** energetic or rigorous or forceful the sync operations are and
701
** only make a difference on Mac OSX for the default SQLite code.
702
** (Third-party VFS implementations might also make the distinction
703
** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
704
** operating systems natively supported by SQLite, only Mac OSX
705
** cares about the difference.)
706
*/
707
#define SQLITE_SYNC_NORMAL        0x00002
708
#define SQLITE_SYNC_FULL          0x00003
709
#define SQLITE_SYNC_DATAONLY      0x00010
710
711
/*
712
** CAPI3REF: OS Interface Open File Handle
713
**
714
** An [sqlite3_file] object represents an open file in the
715
** [sqlite3_vfs | OS interface layer].  Individual OS interface
716
** implementations will
717
** want to subclass this object by appending additional fields
718
** for their own use.  The pMethods entry is a pointer to an
719
** [sqlite3_io_methods] object that defines methods for performing
720
** I/O operations on the open file.
721
*/
722
typedef struct sqlite3_file sqlite3_file;
723
struct sqlite3_file {
724
  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
725
};
726
727
/*
728
** CAPI3REF: OS Interface File Virtual Methods Object
729
**
730
** Every file opened by the [sqlite3_vfs.xOpen] method populates an
731
** [sqlite3_file] object (or, more commonly, a subclass of the
732
** [sqlite3_file] object) with a pointer to an instance of this object.
733
** This object defines the methods used to perform various operations
734
** against the open file represented by the [sqlite3_file] object.
735
**
736
** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
737
** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
738
** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
739
** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
740
** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
741
** to NULL.
742
**
743
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
744
** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
745
** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
746
** flag may be ORed in to indicate that only the data of the file
747
** and not its inode needs to be synced.
748
**
749
** The integer values to xLock() and xUnlock() are one of
750
** <ul>
751
** <li> [SQLITE_LOCK_NONE],
752
** <li> [SQLITE_LOCK_SHARED],
753
** <li> [SQLITE_LOCK_RESERVED],
754
** <li> [SQLITE_LOCK_PENDING], or
755
** <li> [SQLITE_LOCK_EXCLUSIVE].
756
** </ul>
757
** xLock() increases the lock. xUnlock() decreases the lock.
758
** The xCheckReservedLock() method checks whether any database connection,
759
** either in this process or in some other process, is holding a RESERVED,
760
** PENDING, or EXCLUSIVE lock on the file.  It returns true
761
** if such a lock exists and false otherwise.
762
**
763
** The xFileControl() method is a generic interface that allows custom
764
** VFS implementations to directly control an open file using the
765
** [sqlite3_file_control()] interface.  The second "op" argument is an
766
** integer opcode.  The third argument is a generic pointer intended to
767
** point to a structure that may contain arguments or space in which to
768
** write return values.  Potential uses for xFileControl() might be
769
** functions to enable blocking locks with timeouts, to change the
770
** locking strategy (for example to use dot-file locks), to inquire
771
** about the status of a lock, or to break stale locks.  The SQLite
772
** core reserves all opcodes less than 100 for its own use.
773
** A [file control opcodes | list of opcodes] less than 100 is available.
774
** Applications that define a custom xFileControl method should use opcodes
775
** greater than 100 to avoid conflicts.  VFS implementations should
776
** return [SQLITE_NOTFOUND] for file control opcodes that they do not
777
** recognize.
778
**
779
** The xSectorSize() method returns the sector size of the
780
** device that underlies the file.  The sector size is the
781
** minimum write that can be performed without disturbing
782
** other bytes in the file.  The xDeviceCharacteristics()
783
** method returns a bit vector describing behaviors of the
784
** underlying device:
785
**
786
** <ul>
787
** <li> [SQLITE_IOCAP_ATOMIC]
788
** <li> [SQLITE_IOCAP_ATOMIC512]
789
** <li> [SQLITE_IOCAP_ATOMIC1K]
790
** <li> [SQLITE_IOCAP_ATOMIC2K]
791
** <li> [SQLITE_IOCAP_ATOMIC4K]
792
** <li> [SQLITE_IOCAP_ATOMIC8K]
793
** <li> [SQLITE_IOCAP_ATOMIC16K]
794
** <li> [SQLITE_IOCAP_ATOMIC32K]
795
** <li> [SQLITE_IOCAP_ATOMIC64K]
796
** <li> [SQLITE_IOCAP_SAFE_APPEND]
797
** <li> [SQLITE_IOCAP_SEQUENTIAL]
798
** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
799
** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
800
** <li> [SQLITE_IOCAP_IMMUTABLE]
801
** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
802
** </ul>
803
**
804
** The SQLITE_IOCAP_ATOMIC property means that all writes of
805
** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
806
** mean that writes of blocks that are nnn bytes in size and
807
** are aligned to an address which is an integer multiple of
808
** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
809
** that when data is appended to a file, the data is appended
810
** first then the size of the file is extended, never the other
811
** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
812
** information is written to disk in the same order as calls
813
** to xWrite().
814
**
815
** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
816
** in the unread portions of the buffer with zeros.  A VFS that
817
** fails to zero-fill short reads might seem to work.  However,
818
** failure to zero-fill short reads will eventually lead to
819
** database corruption.
820
*/
821
typedef struct sqlite3_io_methods sqlite3_io_methods;
822
struct sqlite3_io_methods {
823
  int iVersion;
824
  int (*xClose)(sqlite3_file*);
825
  int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
826
  int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
827
  int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
828
  int (*xSync)(sqlite3_file*, int flags);
829
  int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
830
  int (*xLock)(sqlite3_file*, int);
831
  int (*xUnlock)(sqlite3_file*, int);
832
  int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
833
  int (*xFileControl)(sqlite3_file*, int op, void *pArg);
834
  int (*xSectorSize)(sqlite3_file*);
835
  int (*xDeviceCharacteristics)(sqlite3_file*);
836
  /* Methods above are valid for version 1 */
837
  int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
838
  int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
839
  void (*xShmBarrier)(sqlite3_file*);
840
  int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
841
  /* Methods above are valid for version 2 */
842
  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
843
  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
844
  /* Methods above are valid for version 3 */
845
  /* Additional methods may be added in future releases */
846
};
847
848
/*
849
** CAPI3REF: Standard File Control Opcodes
850
** KEYWORDS: {file control opcodes} {file control opcode}
851
**
852
** These integer constants are opcodes for the xFileControl method
853
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
854
** interface.
855
**
856
** <ul>
857
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
858
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
859
** opcode causes the xFileControl method to write the current state of
860
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
861
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
862
** into an integer that the pArg argument points to. This capability
863
** is used during testing and is only available when the SQLITE_TEST
864
** compile-time option is used.
865
**
866
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
867
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
868
** layer a hint of how large the database file will grow to be during the
869
** current transaction.  This hint is not guaranteed to be accurate but it
870
** is often close.  The underlying VFS might choose to preallocate database
871
** file space based on this hint in order to help writes to the database
872
** file run faster.
873
**
874
** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
875
** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
876
** implements [sqlite3_deserialize()] to set an upper bound on the size
877
** of the in-memory database.  The argument is a pointer to a [sqlite3_int64].
878
** If the integer pointed to is negative, then it is filled in with the
879
** current limit.  Otherwise the limit is set to the larger of the value
880
** of the integer pointed to and the current database size.  The integer
881
** pointed to is set to the new limit.
882
**
883
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
884
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
885
** extends and truncates the database file in chunks of a size specified
886
** by the user. The fourth argument to [sqlite3_file_control()] should
887
** point to an integer (type int) containing the new chunk-size to use
888
** for the nominated database. Allocating database file space in large
889
** chunks (say 1MB at a time), may reduce file-system fragmentation and
890
** improve performance on some systems.
891
**
892
** <li>[[SQLITE_FCNTL_FILE_POINTER]]
893
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
894
** to the [sqlite3_file] object associated with a particular database
895
** connection.  See also [SQLITE_FCNTL_JOURNAL_POINTER].
896
**
897
** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
898
** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
899
** to the [sqlite3_file] object associated with the journal file (either
900
** the [rollback journal] or the [write-ahead log]) for a particular database
901
** connection.  See also [SQLITE_FCNTL_FILE_POINTER].
902
**
903
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
904
** No longer in use.
905
**
906
** <li>[[SQLITE_FCNTL_SYNC]]
907
** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
908
** sent to the VFS immediately before the xSync method is invoked on a
909
** database file descriptor. Or, if the xSync method is not invoked
910
** because the user has configured SQLite with
911
** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
912
** of the xSync method. In most cases, the pointer argument passed with
913
** this file-control is NULL. However, if the database file is being synced
914
** as part of a multi-database commit, the argument points to a nul-terminated
915
** string containing the transactions super-journal file name. VFSes that
916
** do not need this signal should silently ignore this opcode. Applications
917
** should not call [sqlite3_file_control()] with this opcode as doing so may
918
** disrupt the operation of the specialized VFSes that do require it.
919
**
920
** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
921
** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
922
** and sent to the VFS after a transaction has been committed immediately
923
** but before the database is unlocked. VFSes that do not need this signal
924
** should silently ignore this opcode. Applications should not call
925
** [sqlite3_file_control()] with this opcode as doing so may disrupt the
926
** operation of the specialized VFSes that do require it.
927
**
928
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
929
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
930
** retry counts and intervals for certain disk I/O operations for the
931
** windows [VFS] in order to provide robustness in the presence of
932
** anti-virus programs.  By default, the windows VFS will retry file read,
933
** file write, and file delete operations up to 10 times, with a delay
934
** of 25 milliseconds before the first retry and with the delay increasing
935
** by an additional 25 milliseconds with each subsequent retry.  This
936
** opcode allows these two values (10 retries and 25 milliseconds of delay)
937
** to be adjusted.  The values are changed for all database connections
938
** within the same process.  The argument is a pointer to an array of two
939
** integers where the first integer is the new retry count and the second
940
** integer is the delay.  If either integer is negative, then the setting
941
** is not changed but instead the prior value of that setting is written
942
** into the array entry, allowing the current retry settings to be
943
** interrogated.  The zDbName parameter is ignored.
944
**
945
** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
946
** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
947
** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
948
** write ahead log ([WAL file]) and shared memory
949
** files used for transaction control
950
** are automatically deleted when the latest connection to the database
951
** closes.  Setting persistent WAL mode causes those files to persist after
952
** close.  Persisting the files is useful when other processes that do not
953
** have write permission on the directory containing the database file want
954
** to read the database file, as the WAL and shared memory files must exist
955
** in order for the database to be readable.  The fourth parameter to
956
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
957
** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
958
** WAL mode.  If the integer is -1, then it is overwritten with the current
959
** WAL persistence setting.
960
**
961
** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
962
** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
963
** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
964
** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
965
** xDeviceCharacteristics methods. The fourth parameter to
966
** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
967
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
968
** mode.  If the integer is -1, then it is overwritten with the current
969
** zero-damage mode setting.
970
**
971
** <li>[[SQLITE_FCNTL_OVERWRITE]]
972
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
973
** a write transaction to indicate that, unless it is rolled back for some
974
** reason, the entire database file will be overwritten by the current
975
** transaction. This is used by VACUUM operations.
976
**
977
** <li>[[SQLITE_FCNTL_VFSNAME]]
978
** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
979
** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
980
** final bottom-level VFS are written into memory obtained from
981
** [sqlite3_malloc()] and the result is stored in the char* variable
982
** that the fourth parameter of [sqlite3_file_control()] points to.
983
** The caller is responsible for freeing the memory when done.  As with
984
** all file-control actions, there is no guarantee that this will actually
985
** do anything.  Callers should initialize the char* variable to a NULL
986
** pointer in case this file-control is not implemented.  This file-control
987
** is intended for diagnostic use only.
988
**
989
** <li>[[SQLITE_FCNTL_VFS_POINTER]]
990
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
991
** [VFSes] currently in use.  ^(The argument X in
992
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
993
** of type "[sqlite3_vfs] **".  This opcodes will set *X
994
** to a pointer to the top-level VFS.)^
995
** ^When there are multiple VFS shims in the stack, this opcode finds the
996
** upper-most shim only.
997
**
998
** <li>[[SQLITE_FCNTL_PRAGMA]]
999
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1000
** file control is sent to the open [sqlite3_file] object corresponding
1001
** to the database file to which the pragma statement refers. ^The argument
1002
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
1003
** pointers to strings (char**) in which the second element of the array
1004
** is the name of the pragma and the third element is the argument to the
1005
** pragma or NULL if the pragma has no argument.  ^The handler for an
1006
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
1007
** of the char** argument point to a string obtained from [sqlite3_mprintf()]
1008
** or the equivalent and that string will become the result of the pragma or
1009
** the error message if the pragma fails. ^If the
1010
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1011
** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
1012
** file control returns [SQLITE_OK], then the parser assumes that the
1013
** VFS has handled the PRAGMA itself and the parser generates a no-op
1014
** prepared statement if result string is NULL, or that returns a copy
1015
** of the result string if the string is non-NULL.
1016
** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1017
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
1018
** that the VFS encountered an error while handling the [PRAGMA] and the
1019
** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
1020
** file control occurs at the beginning of pragma statement analysis and so
1021
** it is able to override built-in [PRAGMA] statements.
1022
**
1023
** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1024
** ^The [SQLITE_FCNTL_BUSYHANDLER]
1025
** file-control may be invoked by SQLite on the database file handle
1026
** shortly after it is opened in order to provide a custom VFS with access
1027
** to the connection's busy-handler callback. The argument is of type (void**)
1028
** - an array of two (void *) values. The first (void *) actually points
1029
** to a function of type (int (*)(void *)). In order to invoke the connection's
1030
** busy-handler, this function should be invoked with the second (void *) in
1031
** the array as the only argument. If it returns non-zero, then the operation
1032
** should be retried. If it returns zero, the custom VFS should abandon the
1033
** current operation.
1034
**
1035
** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1036
** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1037
** to have SQLite generate a
1038
** temporary filename using the same algorithm that is followed to generate
1039
** temporary filenames for TEMP tables and other internal uses.  The
1040
** argument should be a char** which will be filled with the filename
1041
** written into memory obtained from [sqlite3_malloc()].  The caller should
1042
** invoke [sqlite3_free()] on the result to avoid a memory leak.
1043
**
1044
** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
1045
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
1046
** maximum number of bytes that will be used for memory-mapped I/O.
1047
** The argument is a pointer to a value of type sqlite3_int64 that
1048
** is an advisory maximum number of bytes in the file to memory map.  The
1049
** pointer is overwritten with the old value.  The limit is not changed if
1050
** the value originally pointed to is negative, and so the current limit
1051
** can be queried by passing in a pointer to a negative number.  This
1052
** file-control is used internally to implement [PRAGMA mmap_size].
1053
**
1054
** <li>[[SQLITE_FCNTL_TRACE]]
1055
** The [SQLITE_FCNTL_TRACE] file control provides advisory information
1056
** to the VFS about what the higher layers of the SQLite stack are doing.
1057
** This file control is used by some VFS activity tracing [shims].
1058
** The argument is a zero-terminated string.  Higher layers in the
1059
** SQLite stack may generate instances of this file control if
1060
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
1061
**
1062
** <li>[[SQLITE_FCNTL_HAS_MOVED]]
1063
** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
1064
** pointer to an integer and it writes a boolean into that integer depending
1065
** on whether or not the file has been renamed, moved, or deleted since it
1066
** was first opened.
1067
**
1068
** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
1069
** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
1070
** underlying native file handle associated with a file handle.  This file
1071
** control interprets its argument as a pointer to a native file handle and
1072
** writes the resulting value there.
1073
**
1074
** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
1075
** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
1076
** opcode causes the xFileControl method to swap the file handle with the one
1077
** pointed to by the pArg argument.  This capability is used during testing
1078
** and only needs to be supported when SQLITE_TEST is defined.
1079
**
1080
** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
1081
** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
1082
** be advantageous to block on the next WAL lock if the lock is not immediately
1083
** available.  The WAL subsystem issues this signal during rare
1084
** circumstances in order to fix a problem with priority inversion.
1085
** Applications should <em>not</em> use this file-control.
1086
**
1087
** <li>[[SQLITE_FCNTL_ZIPVFS]]
1088
** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
1089
** VFS should return SQLITE_NOTFOUND for this opcode.
1090
**
1091
** <li>[[SQLITE_FCNTL_RBU]]
1092
** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
1093
** the RBU extension only.  All other VFS should return SQLITE_NOTFOUND for
1094
** this opcode.
1095
**
1096
** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
1097
** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
1098
** the file descriptor is placed in "batch write mode", which
1099
** means all subsequent write operations will be deferred and done
1100
** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].  Systems
1101
** that do not support batch atomic writes will return SQLITE_NOTFOUND.
1102
** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
1103
** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
1104
** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
1105
** no VFS interface calls on the same [sqlite3_file] file descriptor
1106
** except for calls to the xWrite method and the xFileControl method
1107
** with [SQLITE_FCNTL_SIZE_HINT].
1108
**
1109
** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
1110
** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
1111
** operations since the previous successful call to
1112
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
1113
** This file control returns [SQLITE_OK] if and only if the writes were
1114
** all performed successfully and have been committed to persistent storage.
1115
** ^Regardless of whether or not it is successful, this file control takes
1116
** the file descriptor out of batch write mode so that all subsequent
1117
** write operations are independent.
1118
** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
1119
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1120
**
1121
** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
1122
** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
1123
** operations since the previous successful call to
1124
** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
1125
** ^This file control takes the file descriptor out of batch write mode
1126
** so that all subsequent write operations are independent.
1127
** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
1128
** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
1129
**
1130
** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
1131
** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS
1132
** to block for up to M milliseconds before failing when attempting to
1133
** obtain a file lock using the xLock or xShmLock methods of the VFS.
1134
** The parameter is a pointer to a 32-bit signed integer that contains
1135
** the value that M is to be set to. Before returning, the 32-bit signed
1136
** integer is overwritten with the previous value of M.
1137
**
1138
** <li>[[SQLITE_FCNTL_DATA_VERSION]]
1139
** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
1140
** a database file.  The argument is a pointer to a 32-bit unsigned integer.
1141
** The "data version" for the pager is written into the pointer.  The
1142
** "data version" changes whenever any change occurs to the corresponding
1143
** database file, either through SQL statements on the same database
1144
** connection or through transactions committed by separate database
1145
** connections possibly in other processes. The [sqlite3_total_changes()]
1146
** interface can be used to find if any database on the connection has changed,
1147
** but that interface responds to changes on TEMP as well as MAIN and does
1148
** not provide a mechanism to detect changes to MAIN only.  Also, the
1149
** [sqlite3_total_changes()] interface responds to internal changes only and
1150
** omits changes made by other database connections.  The
1151
** [PRAGMA data_version] command provides a mechanism to detect changes to
1152
** a single attached database that occur due to other database connections,
1153
** but omits changes implemented by the database connection on which it is
1154
** called.  This file control is the only mechanism to detect changes that
1155
** happen either internally or externally and that are associated with
1156
** a particular attached database.
1157
**
1158
** <li>[[SQLITE_FCNTL_CKPT_START]]
1159
** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint
1160
** in wal mode before the client starts to copy pages from the wal
1161
** file to the database file.
1162
**
1163
** <li>[[SQLITE_FCNTL_CKPT_DONE]]
1164
** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint
1165
** in wal mode after the client has finished copying pages from the wal
1166
** file to the database file, but before the *-shm file is updated to
1167
** record the fact that the pages have been checkpointed.
1168
** </ul>
1169
**
1170
** <li>[[SQLITE_FCNTL_EXTERNAL_READER]]
1171
** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect
1172
** whether or not there is a database client in another process with a wal-mode
1173
** transaction open on the database or not. It is only available on unix.The
1174
** (void*) argument passed with this file-control should be a pointer to a
1175
** value of type (int). The integer value is set to 1 if the database is a wal
1176
** mode database and there exists at least one client in another process that
1177
** currently has an SQL transaction open on the database. It is set to 0 if
1178
** the database is not a wal-mode db, or if there is no such connection in any
1179
** other process. This opcode cannot be used to detect transactions opened
1180
** by clients within the current process, only within other processes.
1181
** </ul>
1182
**
1183
** <li>[[SQLITE_FCNTL_CKSM_FILE]]
1184
** Used by the cksmvfs VFS module only.
1185
** </ul>
1186
*/
1187
#define SQLITE_FCNTL_LOCKSTATE               1
1188
#define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
1189
#define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
1190
#define SQLITE_FCNTL_LAST_ERRNO              4
1191
#define SQLITE_FCNTL_SIZE_HINT               5
1192
#define SQLITE_FCNTL_CHUNK_SIZE              6
1193
#define SQLITE_FCNTL_FILE_POINTER            7
1194
#define SQLITE_FCNTL_SYNC_OMITTED            8
1195
#define SQLITE_FCNTL_WIN32_AV_RETRY          9
1196
#define SQLITE_FCNTL_PERSIST_WAL            10
1197
#define SQLITE_FCNTL_OVERWRITE              11
1198
#define SQLITE_FCNTL_VFSNAME                12
1199
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
1200
#define SQLITE_FCNTL_PRAGMA                 14
1201
#define SQLITE_FCNTL_BUSYHANDLER            15
1202
#define SQLITE_FCNTL_TEMPFILENAME           16
1203
#define SQLITE_FCNTL_MMAP_SIZE              18
1204
#define SQLITE_FCNTL_TRACE                  19
1205
#define SQLITE_FCNTL_HAS_MOVED              20
1206
#define SQLITE_FCNTL_SYNC                   21
1207
#define SQLITE_FCNTL_COMMIT_PHASETWO        22
1208
#define SQLITE_FCNTL_WIN32_SET_HANDLE       23
1209
#define SQLITE_FCNTL_WAL_BLOCK              24
1210
#define SQLITE_FCNTL_ZIPVFS                 25
1211
#define SQLITE_FCNTL_RBU                    26
1212
#define SQLITE_FCNTL_VFS_POINTER            27
1213
#define SQLITE_FCNTL_JOURNAL_POINTER        28
1214
#define SQLITE_FCNTL_WIN32_GET_HANDLE       29
1215
#define SQLITE_FCNTL_PDB                    30
1216
#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE     31
1217
#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE    32
1218
#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE  33
1219
#define SQLITE_FCNTL_LOCK_TIMEOUT           34
1220
#define SQLITE_FCNTL_DATA_VERSION           35
1221
#define SQLITE_FCNTL_SIZE_LIMIT             36
1222
#define SQLITE_FCNTL_CKPT_DONE              37
1223
#define SQLITE_FCNTL_RESERVE_BYTES          38
1224
#define SQLITE_FCNTL_CKPT_START             39
1225
#define SQLITE_FCNTL_EXTERNAL_READER        40
1226
#define SQLITE_FCNTL_CKSM_FILE              41
1227
1228
/* deprecated names */
1229
#define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
1230
#define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
1231
#define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO
1232
1233
1234
/*
1235
** CAPI3REF: Mutex Handle
1236
**
1237
** The mutex module within SQLite defines [sqlite3_mutex] to be an
1238
** abstract type for a mutex object.  The SQLite core never looks
1239
** at the internal representation of an [sqlite3_mutex].  It only
1240
** deals with pointers to the [sqlite3_mutex] object.
1241
**
1242
** Mutexes are created using [sqlite3_mutex_alloc()].
1243
*/
1244
typedef struct sqlite3_mutex sqlite3_mutex;
1245
1246
/*
1247
** CAPI3REF: Loadable Extension Thunk
1248
**
1249
** A pointer to the opaque sqlite3_api_routines structure is passed as
1250
** the third parameter to entry points of [loadable extensions].  This
1251
** structure must be typedefed in order to work around compiler warnings
1252
** on some platforms.
1253
*/
1254
typedef struct sqlite3_api_routines sqlite3_api_routines;
1255
1256
/*
1257
** CAPI3REF: OS Interface Object
1258
**
1259
** An instance of the sqlite3_vfs object defines the interface between
1260
** the SQLite core and the underlying operating system.  The "vfs"
1261
** in the name of the object stands for "virtual file system".  See
1262
** the [VFS | VFS documentation] for further information.
1263
**
1264
** The VFS interface is sometimes extended by adding new methods onto
1265
** the end.  Each time such an extension occurs, the iVersion field
1266
** is incremented.  The iVersion value started out as 1 in
1267
** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
1268
** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
1269
** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6].  Additional fields
1270
** may be appended to the sqlite3_vfs object and the iVersion value
1271
** may increase again in future versions of SQLite.
1272
** Note that due to an oversight, the structure
1273
** of the sqlite3_vfs object changed in the transition from
1274
** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
1275
** and yet the iVersion field was not increased.
1276
**
1277
** The szOsFile field is the size of the subclassed [sqlite3_file]
1278
** structure used by this VFS.  mxPathname is the maximum length of
1279
** a pathname in this VFS.
1280
**
1281
** Registered sqlite3_vfs objects are kept on a linked list formed by
1282
** the pNext pointer.  The [sqlite3_vfs_register()]
1283
** and [sqlite3_vfs_unregister()] interfaces manage this list
1284
** in a thread-safe way.  The [sqlite3_vfs_find()] interface
1285
** searches the list.  Neither the application code nor the VFS
1286
** implementation should use the pNext pointer.
1287
**
1288
** The pNext field is the only field in the sqlite3_vfs
1289
** structure that SQLite will ever modify.  SQLite will only access
1290
** or modify this field while holding a particular static mutex.
1291
** The application should never modify anything within the sqlite3_vfs
1292
** object once the object has been registered.
1293
**
1294
** The zName field holds the name of the VFS module.  The name must
1295
** be unique across all VFS modules.
1296
**
1297
** [[sqlite3_vfs.xOpen]]
1298
** ^SQLite guarantees that the zFilename parameter to xOpen
1299
** is either a NULL pointer or string obtained
1300
** from xFullPathname() with an optional suffix added.
1301
** ^If a suffix is added to the zFilename parameter, it will
1302
** consist of a single "-" character followed by no more than
1303
** 11 alphanumeric and/or "-" characters.
1304
** ^SQLite further guarantees that
1305
** the string will be valid and unchanged until xClose() is
1306
** called. Because of the previous sentence,
1307
** the [sqlite3_file] can safely store a pointer to the
1308
** filename if it needs to remember the filename for some reason.
1309
** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1310
** must invent its own temporary name for the file.  ^Whenever the
1311
** xFilename parameter is NULL it will also be the case that the
1312
** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
1313
**
1314
** The flags argument to xOpen() includes all bits set in
1315
** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
1316
** or [sqlite3_open16()] is used, then flags includes at least
1317
** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1318
** If xOpen() opens a file read-only then it sets *pOutFlags to
1319
** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
1320
**
1321
** ^(SQLite will also add one of the following flags to the xOpen()
1322
** call, depending on the object being opened:
1323
**
1324
** <ul>
1325
** <li>  [SQLITE_OPEN_MAIN_DB]
1326
** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
1327
** <li>  [SQLITE_OPEN_TEMP_DB]
1328
** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
1329
** <li>  [SQLITE_OPEN_TRANSIENT_DB]
1330
** <li>  [SQLITE_OPEN_SUBJOURNAL]
1331
** <li>  [SQLITE_OPEN_SUPER_JOURNAL]
1332
** <li>  [SQLITE_OPEN_WAL]
1333
** </ul>)^
1334
**
1335
** The file I/O implementation can use the object type flags to
1336
** change the way it deals with files.  For example, an application
1337
** that does not care about crash recovery or rollback might make
1338
** the open of a journal file a no-op.  Writes to this journal would
1339
** also be no-ops, and any attempt to read the journal would return
1340
** SQLITE_IOERR.  Or the implementation might recognize that a database
1341
** file will be doing page-aligned sector reads and writes in a random
1342
** order and set up its I/O subsystem accordingly.
1343
**
1344
** SQLite might also add one of the following flags to the xOpen method:
1345
**
1346
** <ul>
1347
** <li> [SQLITE_OPEN_DELETEONCLOSE]
1348
** <li> [SQLITE_OPEN_EXCLUSIVE]
1349
** </ul>
1350
**
1351
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
1352
** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
1353
** will be set for TEMP databases and their journals, transient
1354
** databases, and subjournals.
1355
**
1356
** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
1357
** with the [SQLITE_OPEN_CREATE] flag, which are both directly
1358
** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1359
** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1360
** SQLITE_OPEN_CREATE, is used to indicate that file should always
1361
** be created, and that it is an error if it already exists.
1362
** It is <i>not</i> used to indicate the file should be opened
1363
** for exclusive access.
1364
**
1365
** ^At least szOsFile bytes of memory are allocated by SQLite
1366
** to hold the [sqlite3_file] structure passed as the third
1367
** argument to xOpen.  The xOpen method does not have to
1368
** allocate the structure; it should just fill it in.  Note that
1369
** the xOpen method must set the sqlite3_file.pMethods to either
1370
** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
1371
** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
1372
** element will be valid after xOpen returns regardless of the success
1373
** or failure of the xOpen call.
1374
**
1375
** [[sqlite3_vfs.xAccess]]
1376
** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
1377
** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
1378
** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1379
** to test whether a file is at least readable.  The SQLITE_ACCESS_READ
1380
** flag is never actually used and is not implemented in the built-in
1381
** VFSes of SQLite.  The file is named by the second argument and can be a
1382
** directory. The xAccess method returns [SQLITE_OK] on success or some
1383
** non-zero error code if there is an I/O error or if the name of
1384
** the file given in the second argument is illegal.  If SQLITE_OK
1385
** is returned, then non-zero or zero is written into *pResOut to indicate
1386
** whether or not the file is accessible.
1387
**
1388
** ^SQLite will always allocate at least mxPathname+1 bytes for the
1389
** output buffer xFullPathname.  The exact size of the output buffer
1390
** is also passed as a parameter to both  methods. If the output buffer
1391
** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
1392
** handled as a fatal error by SQLite, vfs implementations should endeavor
1393
** to prevent this by setting mxPathname to a sufficiently large value.
1394
**
1395
** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
1396
** interfaces are not strictly a part of the filesystem, but they are
1397
** included in the VFS structure for completeness.
1398
** The xRandomness() function attempts to return nBytes bytes
1399
** of good-quality randomness into zOut.  The return value is
1400
** the actual number of bytes of randomness obtained.
1401
** The xSleep() method causes the calling thread to sleep for at
1402
** least the number of microseconds given.  ^The xCurrentTime()
1403
** method returns a Julian Day Number for the current date and time as
1404
** a floating point value.
1405
** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1406
** Day Number multiplied by 86400000 (the number of milliseconds in
1407
** a 24-hour day).
1408
** ^SQLite will use the xCurrentTimeInt64() method to get the current
1409
** date and time if that method is available (if iVersion is 2 or
1410
** greater and the function pointer is not NULL) and will fall back
1411
** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
1412
**
1413
** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
1414
** are not used by the SQLite core.  These optional interfaces are provided
1415
** by some VFSes to facilitate testing of the VFS code. By overriding
1416
** system calls with functions under its control, a test program can
1417
** simulate faults and error conditions that would otherwise be difficult
1418
** or impossible to induce.  The set of system calls that can be overridden
1419
** varies from one VFS to another, and from one version of the same VFS to the
1420
** next.  Applications that use these interfaces must be prepared for any
1421
** or all of these interfaces to be NULL or for their behavior to change
1422
** from one release to the next.  Applications must not attempt to access
1423
** any of these methods if the iVersion of the VFS is less than 3.
1424
*/
1425
typedef struct sqlite3_vfs sqlite3_vfs;
1426
typedef void (*sqlite3_syscall_ptr)(void);
1427
struct sqlite3_vfs {
1428
  int iVersion;            /* Structure version number (currently 3) */
1429
  int szOsFile;            /* Size of subclassed sqlite3_file */
1430
  int mxPathname;          /* Maximum file pathname length */
1431
  sqlite3_vfs *pNext;      /* Next registered VFS */
1432
  const char *zName;       /* Name of this virtual file system */
1433
  void *pAppData;          /* Pointer to application-specific data */
1434
  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
1435
               int flags, int *pOutFlags);
1436
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
1437
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
1438
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
1439
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
1440
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
1441
  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
1442
  void (*xDlClose)(sqlite3_vfs*, void*);
1443
  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
1444
  int (*xSleep)(sqlite3_vfs*, int microseconds);
1445
  int (*xCurrentTime)(sqlite3_vfs*, double*);
1446
  int (*xGetLastError)(sqlite3_vfs*, int, char *);
1447
  /*
1448
  ** The methods above are in version 1 of the sqlite_vfs object
1449
  ** definition.  Those that follow are added in version 2 or later
1450
  */
1451
  int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
1452
  /*
1453
  ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
1454
  ** Those below are for version 3 and greater.
1455
  */
1456
  int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
1457
  sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
1458
  const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
1459
  /*
1460
  ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1461
  ** New fields may be appended in future versions.  The iVersion
1462
  ** value will increment whenever this happens.
1463
  */
1464
};
1465
1466
/*
1467
** CAPI3REF: Flags for the xAccess VFS method
1468
**
1469
** These integer constants can be used as the third parameter to
1470
** the xAccess method of an [sqlite3_vfs] object.  They determine
1471
** what kind of permissions the xAccess method is looking for.
1472
** With SQLITE_ACCESS_EXISTS, the xAccess method
1473
** simply checks whether the file exists.
1474
** With SQLITE_ACCESS_READWRITE, the xAccess method
1475
** checks whether the named directory is both readable and writable
1476
** (in other words, if files can be added, removed, and renamed within
1477
** the directory).
1478
** The SQLITE_ACCESS_READWRITE constant is currently used only by the
1479
** [temp_store_directory pragma], though this could change in a future
1480
** release of SQLite.
1481
** With SQLITE_ACCESS_READ, the xAccess method
1482
** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
1483
** currently unused, though it might be used in a future release of
1484
** SQLite.
1485
*/
1486
#define SQLITE_ACCESS_EXISTS    0
1487
#define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
1488
#define SQLITE_ACCESS_READ      2   /* Unused */
1489
1490
/*
1491
** CAPI3REF: Flags for the xShmLock VFS method
1492
**
1493
** These integer constants define the various locking operations
1494
** allowed by the xShmLock method of [sqlite3_io_methods].  The
1495
** following are the only legal combinations of flags to the
1496
** xShmLock method:
1497
**
1498
** <ul>
1499
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
1500
** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
1501
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
1502
** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
1503
** </ul>
1504
**
1505
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1506
** was given on the corresponding lock.
1507
**
1508
** The xShmLock method can transition between unlocked and SHARED or
1509
** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
1510
** and EXCLUSIVE.
1511
*/
1512
#define SQLITE_SHM_UNLOCK       1
1513
#define SQLITE_SHM_LOCK         2
1514
#define SQLITE_SHM_SHARED       4
1515
#define SQLITE_SHM_EXCLUSIVE    8
1516
1517
/*
1518
** CAPI3REF: Maximum xShmLock index
1519
**
1520
** The xShmLock method on [sqlite3_io_methods] may use values
1521
** between 0 and this upper bound as its "offset" argument.
1522
** The SQLite core will never attempt to acquire or release a
1523
** lock outside of this range
1524
*/
1525
#define SQLITE_SHM_NLOCK        8
1526
1527
1528
/*
1529
** CAPI3REF: Initialize The SQLite Library
1530
**
1531
** ^The sqlite3_initialize() routine initializes the
1532
** SQLite library.  ^The sqlite3_shutdown() routine
1533
** deallocates any resources that were allocated by sqlite3_initialize().
1534
** These routines are designed to aid in process initialization and
1535
** shutdown on embedded systems.  Workstation applications using
1536
** SQLite normally do not need to invoke either of these routines.
1537
**
1538
** A call to sqlite3_initialize() is an "effective" call if it is
1539
** the first time sqlite3_initialize() is invoked during the lifetime of
1540
** the process, or if it is the first time sqlite3_initialize() is invoked
1541
** following a call to sqlite3_shutdown().  ^(Only an effective call
1542
** of sqlite3_initialize() does any initialization.  All other calls
1543
** are harmless no-ops.)^
1544
**
1545
** A call to sqlite3_shutdown() is an "effective" call if it is the first
1546
** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
1547
** an effective call to sqlite3_shutdown() does any deinitialization.
1548
** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
1549
**
1550
** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
1551
** is not.  The sqlite3_shutdown() interface must only be called from a
1552
** single thread.  All open [database connections] must be closed and all
1553
** other SQLite resources must be deallocated prior to invoking
1554
** sqlite3_shutdown().
1555
**
1556
** Among other things, ^sqlite3_initialize() will invoke
1557
** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
1558
** will invoke sqlite3_os_end().
1559
**
1560
** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
1561
** ^If for some reason, sqlite3_initialize() is unable to initialize
1562
** the library (perhaps it is unable to allocate a needed resource such
1563
** as a mutex) it returns an [error code] other than [SQLITE_OK].
1564
**
1565
** ^The sqlite3_initialize() routine is called internally by many other
1566
** SQLite interfaces so that an application usually does not need to
1567
** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
1568
** calls sqlite3_initialize() so the SQLite library will be automatically
1569
** initialized when [sqlite3_open()] is called if it has not be initialized
1570
** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
1571
** compile-time option, then the automatic calls to sqlite3_initialize()
1572
** are omitted and the application must call sqlite3_initialize() directly
1573
** prior to using any other SQLite interface.  For maximum portability,
1574
** it is recommended that applications always invoke sqlite3_initialize()
1575
** directly prior to using any other SQLite interface.  Future releases
1576
** of SQLite may require this.  In other words, the behavior exhibited
1577
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
1578
** default behavior in some future release of SQLite.
1579
**
1580
** The sqlite3_os_init() routine does operating-system specific
1581
** initialization of the SQLite library.  The sqlite3_os_end()
1582
** routine undoes the effect of sqlite3_os_init().  Typical tasks
1583
** performed by these routines include allocation or deallocation
1584
** of static resources, initialization of global variables,
1585
** setting up a default [sqlite3_vfs] module, or setting up
1586
** a default configuration using [sqlite3_config()].
1587
**
1588
** The application should never invoke either sqlite3_os_init()
1589
** or sqlite3_os_end() directly.  The application should only invoke
1590
** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
1591
** interface is called automatically by sqlite3_initialize() and
1592
** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
1593
** implementations for sqlite3_os_init() and sqlite3_os_end()
1594
** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
1595
** When [custom builds | built for other platforms]
1596
** (using the [SQLITE_OS_OTHER=1] compile-time
1597
** option) the application must supply a suitable implementation for
1598
** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
1599
** implementation of sqlite3_os_init() or sqlite3_os_end()
1600
** must return [SQLITE_OK] on success and some other [error code] upon
1601
** failure.
1602
*/
1603
SQLITE_API int sqlite3_initialize(void);
1604
SQLITE_API int sqlite3_shutdown(void);
1605
SQLITE_API int sqlite3_os_init(void);
1606
SQLITE_API int sqlite3_os_end(void);
1607
1608
/*
1609
** CAPI3REF: Configuring The SQLite Library
1610
**
1611
** The sqlite3_config() interface is used to make global configuration
1612
** changes to SQLite in order to tune SQLite to the specific needs of
1613
** the application.  The default configuration is recommended for most
1614
** applications and so this routine is usually not necessary.  It is
1615
** provided to support rare applications with unusual needs.
1616
**
1617
** <b>The sqlite3_config() interface is not threadsafe. The application
1618
** must ensure that no other SQLite interfaces are invoked by other
1619
** threads while sqlite3_config() is running.</b>
1620
**
1621
** The sqlite3_config() interface
1622
** may only be invoked prior to library initialization using
1623
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
1624
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1625
** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1626
** Note, however, that ^sqlite3_config() can be called as part of the
1627
** implementation of an application-defined [sqlite3_os_init()].
1628
**
1629
** The first argument to sqlite3_config() is an integer
1630
** [configuration option] that determines
1631
** what property of SQLite is to be configured.  Subsequent arguments
1632
** vary depending on the [configuration option]
1633
** in the first argument.
1634
**
1635
** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1636
** ^If the option is unknown or SQLite is unable to set the option
1637
** then this routine returns a non-zero [error code].
1638
*/
1639
SQLITE_API int sqlite3_config(int, ...);
1640
1641
/*
1642
** CAPI3REF: Configure database connections
1643
** METHOD: sqlite3
1644
**
1645
** The sqlite3_db_config() interface is used to make configuration
1646
** changes to a [database connection].  The interface is similar to
1647
** [sqlite3_config()] except that the changes apply to a single
1648
** [database connection] (specified in the first argument).
1649
**
1650
** The second argument to sqlite3_db_config(D,V,...)  is the
1651
** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1652
** that indicates what aspect of the [database connection] is being configured.
1653
** Subsequent arguments vary depending on the configuration verb.
1654
**
1655
** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1656
** the call is considered successful.
1657
*/
1658
SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
1659
1660
/*
1661
** CAPI3REF: Memory Allocation Routines
1662
**
1663
** An instance of this object defines the interface between SQLite
1664
** and low-level memory allocation routines.
1665
**
1666
** This object is used in only one place in the SQLite interface.
1667
** A pointer to an instance of this object is the argument to
1668
** [sqlite3_config()] when the configuration option is
1669
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1670
** By creating an instance of this object
1671
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1672
** during configuration, an application can specify an alternative
1673
** memory allocation subsystem for SQLite to use for all of its
1674
** dynamic memory needs.
1675
**
1676
** Note that SQLite comes with several [built-in memory allocators]
1677
** that are perfectly adequate for the overwhelming majority of applications
1678
** and that this object is only useful to a tiny minority of applications
1679
** with specialized memory allocation requirements.  This object is
1680
** also used during testing of SQLite in order to specify an alternative
1681
** memory allocator that simulates memory out-of-memory conditions in
1682
** order to verify that SQLite recovers gracefully from such
1683
** conditions.
1684
**
1685
** The xMalloc, xRealloc, and xFree methods must work like the
1686
** malloc(), realloc() and free() functions from the standard C library.
1687
** ^SQLite guarantees that the second argument to
1688
** xRealloc is always a value returned by a prior call to xRoundup.
1689
**
1690
** xSize should return the allocated size of a memory allocation
1691
** previously obtained from xMalloc or xRealloc.  The allocated size
1692
** is always at least as big as the requested size but may be larger.
1693
**
1694
** The xRoundup method returns what would be the allocated size of
1695
** a memory allocation given a particular requested size.  Most memory
1696
** allocators round up memory allocations at least to the next multiple
1697
** of 8.  Some allocators round up to a larger multiple or to a power of 2.
1698
** Every memory allocation request coming in through [sqlite3_malloc()]
1699
** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0,
1700
** that causes the corresponding memory allocation to fail.
1701
**
1702
** The xInit method initializes the memory allocator.  For example,
1703
** it might allocate any required mutexes or initialize internal data
1704
** structures.  The xShutdown method is invoked (indirectly) by
1705
** [sqlite3_shutdown()] and should deallocate any resources acquired
1706
** by xInit.  The pAppData pointer is used as the only parameter to
1707
** xInit and xShutdown.
1708
**
1709
** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes
1710
** the xInit method, so the xInit method need not be threadsafe.  The
1711
** xShutdown method is only called from [sqlite3_shutdown()] so it does
1712
** not need to be threadsafe either.  For all other methods, SQLite
1713
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1714
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1715
** it is by default) and so the methods are automatically serialized.
1716
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1717
** methods must be threadsafe or else make their own arrangements for
1718
** serialization.
1719
**
1720
** SQLite will never invoke xInit() more than once without an intervening
1721
** call to xShutdown().
1722
*/
1723
typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1724
struct sqlite3_mem_methods {
1725
  void *(*xMalloc)(int);         /* Memory allocation function */
1726
  void (*xFree)(void*);          /* Free a prior allocation */
1727
  void *(*xRealloc)(void*,int);  /* Resize an allocation */
1728
  int (*xSize)(void*);           /* Return the size of an allocation */
1729
  int (*xRoundup)(int);          /* Round up request size to allocation size */
1730
  int (*xInit)(void*);           /* Initialize the memory allocator */
1731
  void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
1732
  void *pAppData;                /* Argument to xInit() and xShutdown() */
1733
};
1734
1735
/*
1736
** CAPI3REF: Configuration Options
1737
** KEYWORDS: {configuration option}
1738
**
1739
** These constants are the available integer configuration options that
1740
** can be passed as the first argument to the [sqlite3_config()] interface.
1741
**
1742
** New configuration options may be added in future releases of SQLite.
1743
** Existing configuration options might be discontinued.  Applications
1744
** should check the return code from [sqlite3_config()] to make sure that
1745
** the call worked.  The [sqlite3_config()] interface will return a
1746
** non-zero [error code] if a discontinued or unsupported configuration option
1747
** is invoked.
1748
**
1749
** <dl>
1750
** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
1751
** <dd>There are no arguments to this option.  ^This option sets the
1752
** [threading mode] to Single-thread.  In other words, it disables
1753
** all mutexing and puts SQLite into a mode where it can only be used
1754
** by a single thread.   ^If SQLite is compiled with
1755
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1756
** it is not possible to change the [threading mode] from its default
1757
** value of Single-thread and so [sqlite3_config()] will return
1758
** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1759
** configuration option.</dd>
1760
**
1761
** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
1762
** <dd>There are no arguments to this option.  ^This option sets the
1763
** [threading mode] to Multi-thread.  In other words, it disables
1764
** mutexing on [database connection] and [prepared statement] objects.
1765
** The application is responsible for serializing access to
1766
** [database connections] and [prepared statements].  But other mutexes
1767
** are enabled so that SQLite will be safe to use in a multi-threaded
1768
** environment as long as no two threads attempt to use the same
1769
** [database connection] at the same time.  ^If SQLite is compiled with
1770
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1771
** it is not possible to set the Multi-thread [threading mode] and
1772
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1773
** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
1774
**
1775
** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
1776
** <dd>There are no arguments to this option.  ^This option sets the
1777
** [threading mode] to Serialized. In other words, this option enables
1778
** all mutexes including the recursive
1779
** mutexes on [database connection] and [prepared statement] objects.
1780
** In this mode (which is the default when SQLite is compiled with
1781
** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
1782
** to [database connections] and [prepared statements] so that the
1783
** application is free to use the same [database connection] or the
1784
** same [prepared statement] in different threads at the same time.
1785
** ^If SQLite is compiled with
1786
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1787
** it is not possible to set the Serialized [threading mode] and
1788
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1789
** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
1790
**
1791
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1792
** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1793
** a pointer to an instance of the [sqlite3_mem_methods] structure.
1794
** The argument specifies
1795
** alternative low-level memory allocation routines to be used in place of
1796
** the memory allocation routines built into SQLite.)^ ^SQLite makes
1797
** its own private copy of the content of the [sqlite3_mem_methods] structure
1798
** before the [sqlite3_config()] call returns.</dd>
1799
**
1800
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1801
** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
1802
** is a pointer to an instance of the [sqlite3_mem_methods] structure.
1803
** The [sqlite3_mem_methods]
1804
** structure is filled with the currently defined memory allocation routines.)^
1805
** This option can be used to overload the default memory allocation
1806
** routines with a wrapper that simulations memory allocation failure or
1807
** tracks memory usage, for example. </dd>
1808
**
1809
** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
1810
** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
1811
** type int, interpreted as a boolean, which if true provides a hint to
1812
** SQLite that it should avoid large memory allocations if possible.
1813
** SQLite will run faster if it is free to make large memory allocations,
1814
** but some application might prefer to run slower in exchange for
1815
** guarantees about memory fragmentation that are possible if large
1816
** allocations are avoided.  This hint is normally off.
1817
** </dd>
1818
**
1819
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1820
** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
1821
** interpreted as a boolean, which enables or disables the collection of
1822
** memory allocation statistics. ^(When memory allocation statistics are
1823
** disabled, the following SQLite interfaces become non-operational:
1824
**   <ul>
1825
**   <li> [sqlite3_hard_heap_limit64()]
1826
**   <li> [sqlite3_memory_used()]
1827
**   <li> [sqlite3_memory_highwater()]
1828
**   <li> [sqlite3_soft_heap_limit64()]
1829
**   <li> [sqlite3_status64()]
1830
**   </ul>)^
1831
** ^Memory allocation statistics are enabled by default unless SQLite is
1832
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1833
** allocation statistics are disabled by default.
1834
** </dd>
1835
**
1836
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1837
** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1838
** </dd>
1839
**
1840
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1841
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
1842
** that SQLite can use for the database page cache with the default page
1843
** cache implementation.
1844
** This configuration option is a no-op if an application-defined page
1845
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
1846
** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
1847
** 8-byte aligned memory (pMem), the size of each page cache line (sz),
1848
** and the number of cache lines (N).
1849
** The sz argument should be the size of the largest database page
1850
** (a power of two between 512 and 65536) plus some extra bytes for each
1851
** page header.  ^The number of extra bytes needed by the page header
1852
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
1853
** ^It is harmless, apart from the wasted memory,
1854
** for the sz parameter to be larger than necessary.  The pMem
1855
** argument must be either a NULL pointer or a pointer to an 8-byte
1856
** aligned block of memory of at least sz*N bytes, otherwise
1857
** subsequent behavior is undefined.
1858
** ^When pMem is not NULL, SQLite will strive to use the memory provided
1859
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
1860
** a page cache line is larger than sz bytes or if all of the pMem buffer
1861
** is exhausted.
1862
** ^If pMem is NULL and N is non-zero, then each database connection
1863
** does an initial bulk allocation for page cache memory
1864
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
1865
** of -1024*N bytes if N is negative, . ^If additional
1866
** page cache memory is needed beyond what is provided by the initial
1867
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
1868
** additional cache line. </dd>
1869
**
1870
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1871
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1872
** that SQLite will use for all of its dynamic memory allocation needs
1873
** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1874
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
1875
** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
1876
** [SQLITE_ERROR] if invoked otherwise.
1877
** ^There are three arguments to SQLITE_CONFIG_HEAP:
1878
** An 8-byte aligned pointer to the memory,
1879
** the number of bytes in the memory buffer, and the minimum allocation size.
1880
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
1881
** to using its default memory allocator (the system malloc() implementation),
1882
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
1883
** memory pointer is not NULL then the alternative memory
1884
** allocator is engaged to handle all of SQLites memory allocation needs.
1885
** The first pointer (the memory pointer) must be aligned to an 8-byte
1886
** boundary or subsequent behavior of SQLite will be undefined.
1887
** The minimum allocation size is capped at 2**12. Reasonable values
1888
** for the minimum allocation size are 2**5 through 2**8.</dd>
1889
**
1890
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1891
** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
1892
** pointer to an instance of the [sqlite3_mutex_methods] structure.
1893
** The argument specifies alternative low-level mutex routines to be used
1894
** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
1895
** the content of the [sqlite3_mutex_methods] structure before the call to
1896
** [sqlite3_config()] returns. ^If SQLite is compiled with
1897
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1898
** the entire mutexing subsystem is omitted from the build and hence calls to
1899
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1900
** return [SQLITE_ERROR].</dd>
1901
**
1902
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1903
** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
1904
** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
1905
** [sqlite3_mutex_methods]
1906
** structure is filled with the currently defined mutex routines.)^
1907
** This option can be used to overload the default mutex allocation
1908
** routines with a wrapper used to track mutex usage for performance
1909
** profiling or testing, for example.   ^If SQLite is compiled with
1910
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1911
** the entire mutexing subsystem is omitted from the build and hence calls to
1912
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1913
** return [SQLITE_ERROR].</dd>
1914
**
1915
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1916
** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
1917
** the default size of lookaside memory on each [database connection].
1918
** The first argument is the
1919
** size of each lookaside buffer slot and the second is the number of
1920
** slots allocated to each database connection.)^  ^(SQLITE_CONFIG_LOOKASIDE
1921
** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
1922
** option to [sqlite3_db_config()] can be used to change the lookaside
1923
** configuration on individual connections.)^ </dd>
1924
**
1925
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1926
** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
1927
** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
1928
** the interface to a custom page cache implementation.)^
1929
** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1930
**
1931
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1932
** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
1933
** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
1934
** the current page cache implementation into that object.)^ </dd>
1935
**
1936
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1937
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
1938
** global [error log].
1939
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1940
** function with a call signature of void(*)(void*,int,const char*),
1941
** and a pointer to void. ^If the function pointer is not NULL, it is
1942
** invoked by [sqlite3_log()] to process each logging event.  ^If the
1943
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1944
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1945
** passed through as the first parameter to the application-defined logger
1946
** function whenever that function is invoked.  ^The second parameter to
1947
** the logger function is a copy of the first parameter to the corresponding
1948
** [sqlite3_log()] call and is intended to be a [result code] or an
1949
** [extended result code].  ^The third parameter passed to the logger is
1950
** log message after formatting via [sqlite3_snprintf()].
1951
** The SQLite logging interface is not reentrant; the logger function
1952
** supplied by the application must not invoke any SQLite interface.
1953
** In a multi-threaded application, the application-defined logger
1954
** function must be threadsafe. </dd>
1955
**
1956
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1957
** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
1958
** If non-zero, then URI handling is globally enabled. If the parameter is zero,
1959
** then URI handling is globally disabled.)^ ^If URI handling is globally
1960
** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
1961
** [sqlite3_open16()] or
1962
** specified as part of [ATTACH] commands are interpreted as URIs, regardless
1963
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1964
** connection is opened. ^If it is globally disabled, filenames are
1965
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1966
** database connection is opened. ^(By default, URI handling is globally
1967
** disabled. The default value may be changed by compiling with the
1968
** [SQLITE_USE_URI] symbol defined.)^
1969
**
1970
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1971
** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
1972
** argument which is interpreted as a boolean in order to enable or disable
1973
** the use of covering indices for full table scans in the query optimizer.
1974
** ^The default setting is determined
1975
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
1976
** if that compile-time option is omitted.
1977
** The ability to disable the use of covering indices for full table scans
1978
** is because some incorrectly coded legacy applications might malfunction
1979
** when the optimization is enabled.  Providing the ability to
1980
** disable the optimization allows the older, buggy application code to work
1981
** without change even with newer versions of SQLite.
1982
**
1983
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1984
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1985
** <dd> These options are obsolete and should not be used by new code.
1986
** They are retained for backwards compatibility but are now no-ops.
1987
** </dd>
1988
**
1989
** [[SQLITE_CONFIG_SQLLOG]]
1990
** <dt>SQLITE_CONFIG_SQLLOG
1991
** <dd>This option is only available if sqlite is compiled with the
1992
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1993
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
1994
** The second should be of type (void*). The callback is invoked by the library
1995
** in three separate circumstances, identified by the value passed as the
1996
** fourth parameter. If the fourth parameter is 0, then the database connection
1997
** passed as the second argument has just been opened. The third argument
1998
** points to a buffer containing the name of the main database file. If the
1999
** fourth parameter is 1, then the SQL statement that the third parameter
2000
** points to has just been executed. Or, if the fourth parameter is 2, then
2001
** the connection being passed as the second parameter is being closed. The
2002
** third parameter is passed NULL In this case.  An example of using this
2003
** configuration option can be seen in the "test_sqllog.c" source file in
2004
** the canonical SQLite source tree.</dd>
2005
**
2006
** [[SQLITE_CONFIG_MMAP_SIZE]]
2007
** <dt>SQLITE_CONFIG_MMAP_SIZE
2008
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
2009
** that are the default mmap size limit (the default setting for
2010
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
2011
** ^The default setting can be overridden by each database connection using
2012
** either the [PRAGMA mmap_size] command, or by using the
2013
** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
2014
** will be silently truncated if necessary so that it does not exceed the
2015
** compile-time maximum mmap size set by the
2016
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
2017
** ^If either argument to this option is negative, then that argument is
2018
** changed to its compile-time default.
2019
**
2020
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
2021
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
2022
** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
2023
** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
2024
** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
2025
** that specifies the maximum size of the created heap.
2026
**
2027
** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
2028
** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
2029
** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
2030
** is a pointer to an integer and writes into that integer the number of extra
2031
** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
2032
** The amount of extra space required can change depending on the compiler,
2033
** target platform, and SQLite version.
2034
**
2035
** [[SQLITE_CONFIG_PMASZ]]
2036
** <dt>SQLITE_CONFIG_PMASZ
2037
** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
2038
** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
2039
** sorter to that integer.  The default minimum PMA Size is set by the
2040
** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
2041
** to help with sort operations when multithreaded sorting
2042
** is enabled (using the [PRAGMA threads] command) and the amount of content
2043
** to be sorted exceeds the page size times the minimum of the
2044
** [PRAGMA cache_size] setting and this value.
2045
**
2046
** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
2047
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
2048
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
2049
** becomes the [statement journal] spill-to-disk threshold.
2050
** [Statement journals] are held in memory until their size (in bytes)
2051
** exceeds this threshold, at which point they are written to disk.
2052
** Or if the threshold is -1, statement journals are always held
2053
** exclusively in memory.
2054
** Since many statement journals never become large, setting the spill
2055
** threshold to a value such as 64KiB can greatly reduce the amount of
2056
** I/O required to support statement rollback.
2057
** The default value for this setting is controlled by the
2058
** [SQLITE_STMTJRNL_SPILL] compile-time option.
2059
**
2060
** [[SQLITE_CONFIG_SORTERREF_SIZE]]
2061
** <dt>SQLITE_CONFIG_SORTERREF_SIZE
2062
** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
2063
** of type (int) - the new value of the sorter-reference size threshold.
2064
** Usually, when SQLite uses an external sort to order records according
2065
** to an ORDER BY clause, all fields required by the caller are present in the
2066
** sorted records. However, if SQLite determines based on the declared type
2067
** of a table column that its values are likely to be very large - larger
2068
** than the configured sorter-reference size threshold - then a reference
2069
** is stored in each sorted record and the required column values loaded
2070
** from the database as records are returned in sorted order. The default
2071
** value for this option is to never use this optimization. Specifying a
2072
** negative value for this option restores the default behaviour.
2073
** This option is only available if SQLite is compiled with the
2074
** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
2075
**
2076
** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
2077
** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
2078
** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
2079
** [sqlite3_int64] parameter which is the default maximum size for an in-memory
2080
** database created using [sqlite3_deserialize()].  This default maximum
2081
** size can be adjusted up or down for individual databases using the
2082
** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control].  If this
2083
** configuration setting is never used, then the default maximum is determined
2084
** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option.  If that
2085
** compile-time option is not set, then the default maximum is 1073741824.
2086
** </dl>
2087
*/
2088
#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
2089
#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
2090
#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
2091
#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
2092
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
2093
#define SQLITE_CONFIG_SCRATCH       6  /* No longer used */
2094
#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
2095
#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
2096
#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
2097
#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
2098
#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
2099
/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
2100
#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
2101
#define SQLITE_CONFIG_PCACHE       14  /* no-op */
2102
#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
2103
#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
2104
#define SQLITE_CONFIG_URI          17  /* int */
2105
#define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
2106
#define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
2107
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
2108
#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
2109
#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
2110
#define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
2111
#define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
2112
#define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
2113
#define SQLITE_CONFIG_STMTJRNL_SPILL      26  /* int nByte */
2114
#define SQLITE_CONFIG_SMALL_MALLOC        27  /* boolean */
2115
#define SQLITE_CONFIG_SORTERREF_SIZE      28  /* int nByte */
2116
#define SQLITE_CONFIG_MEMDB_MAXSIZE       29  /* sqlite3_int64 */
2117
2118
/*
2119
** CAPI3REF: Database Connection Configuration Options
2120
**
2121
** These constants are the available integer configuration options that
2122
** can be passed as the second argument to the [sqlite3_db_config()] interface.
2123
**
2124
** New configuration options may be added in future releases of SQLite.
2125
** Existing configuration options might be discontinued.  Applications
2126
** should check the return code from [sqlite3_db_config()] to make sure that
2127
** the call worked.  ^The [sqlite3_db_config()] interface will return a
2128
** non-zero [error code] if a discontinued or unsupported configuration option
2129
** is invoked.
2130
**
2131
** <dl>
2132
** [[SQLITE_DBCONFIG_LOOKASIDE]]
2133
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
2134
** <dd> ^This option takes three additional arguments that determine the
2135
** [lookaside memory allocator] configuration for the [database connection].
2136
** ^The first argument (the third parameter to [sqlite3_db_config()] is a
2137
** pointer to a memory buffer to use for lookaside memory.
2138
** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
2139
** may be NULL in which case SQLite will allocate the
2140
** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
2141
** size of each lookaside buffer slot.  ^The third argument is the number of
2142
** slots.  The size of the buffer in the first argument must be greater than
2143
** or equal to the product of the second and third arguments.  The buffer
2144
** must be aligned to an 8-byte boundary.  ^If the second argument to
2145
** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
2146
** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
2147
** configuration for a database connection can only be changed when that
2148
** connection is not currently using lookaside memory, or in other words
2149
** when the "current value" returned by
2150
** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
2151
** Any attempt to change the lookaside memory configuration when lookaside
2152
** memory is in use leaves the configuration unchanged and returns
2153
** [SQLITE_BUSY].)^</dd>
2154
**
2155
** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
2156
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
2157
** <dd> ^This option is used to enable or disable the enforcement of
2158
** [foreign key constraints].  There should be two additional arguments.
2159
** The first argument is an integer which is 0 to disable FK enforcement,
2160
** positive to enable FK enforcement or negative to leave FK enforcement
2161
** unchanged.  The second parameter is a pointer to an integer into which
2162
** is written 0 or 1 to indicate whether FK enforcement is off or on
2163
** following this call.  The second parameter may be a NULL pointer, in
2164
** which case the FK enforcement setting is not reported back. </dd>
2165
**
2166
** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]]
2167
** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
2168
** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
2169
** There should be two additional arguments.
2170
** The first argument is an integer which is 0 to disable triggers,
2171
** positive to enable triggers or negative to leave the setting unchanged.
2172
** The second parameter is a pointer to an integer into which
2173
** is written 0 or 1 to indicate whether triggers are disabled or enabled
2174
** following this call.  The second parameter may be a NULL pointer, in
2175
** which case the trigger setting is not reported back.
2176
**
2177
** <p>Originally this option disabled all triggers.  ^(However, since
2178
** SQLite version 3.35.0, TEMP triggers are still allowed even if
2179
** this option is off.  So, in other words, this option now only disables
2180
** triggers in the main database schema or in the schemas of ATTACH-ed
2181
** databases.)^ </dd>
2182
**
2183
** [[SQLITE_DBCONFIG_ENABLE_VIEW]]
2184
** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt>
2185
** <dd> ^This option is used to enable or disable [CREATE VIEW | views].
2186
** There should be two additional arguments.
2187
** The first argument is an integer which is 0 to disable views,
2188
** positive to enable views or negative to leave the setting unchanged.
2189
** The second parameter is a pointer to an integer into which
2190
** is written 0 or 1 to indicate whether views are disabled or enabled
2191
** following this call.  The second parameter may be a NULL pointer, in
2192
** which case the view setting is not reported back.
2193
**
2194
** <p>Originally this option disabled all views.  ^(However, since
2195
** SQLite version 3.35.0, TEMP views are still allowed even if
2196
** this option is off.  So, in other words, this option now only disables
2197
** views in the main database schema or in the schemas of ATTACH-ed
2198
** databases.)^ </dd>
2199
**
2200
** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
2201
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
2202
** <dd> ^This option is used to enable or disable the
2203
** [fts3_tokenizer()] function which is part of the
2204
** [FTS3] full-text search engine extension.
2205
** There should be two additional arguments.
2206
** The first argument is an integer which is 0 to disable fts3_tokenizer() or
2207
** positive to enable fts3_tokenizer() or negative to leave the setting
2208
** unchanged.
2209
** The second parameter is a pointer to an integer into which
2210
** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
2211
** following this call.  The second parameter may be a NULL pointer, in
2212
** which case the new setting is not reported back. </dd>
2213
**
2214
** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]]
2215
** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
2216
** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
2217
** interface independently of the [load_extension()] SQL function.
2218
** The [sqlite3_enable_load_extension()] API enables or disables both the
2219
** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
2220
** There should be two additional arguments.
2221
** When the first argument to this interface is 1, then only the C-API is
2222
** enabled and the SQL function remains disabled.  If the first argument to
2223
** this interface is 0, then both the C-API and the SQL function are disabled.
2224
** If the first argument is -1, then no changes are made to state of either the
2225
** C-API or the SQL function.
2226
** The second parameter is a pointer to an integer into which
2227
** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
2228
** is disabled or enabled following this call.  The second parameter may
2229
** be a NULL pointer, in which case the new setting is not reported back.
2230
** </dd>
2231
**
2232
** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
2233
** <dd> ^This option is used to change the name of the "main" database
2234
** schema.  ^The sole argument is a pointer to a constant UTF8 string
2235
** which will become the new schema name in place of "main".  ^SQLite
2236
** does not make a copy of the new main schema name string, so the application
2237
** must ensure that the argument passed into this DBCONFIG option is unchanged
2238
** until after the database connection closes.
2239
** </dd>
2240
**
2241
** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
2242
** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
2243
** <dd> Usually, when a database in wal mode is closed or detached from a
2244
** database handle, SQLite checks if this will mean that there are now no
2245
** connections at all to the database. If so, it performs a checkpoint
2246
** operation before closing the connection. This option may be used to
2247
** override this behaviour. The first parameter passed to this operation
2248
** is an integer - positive to disable checkpoints-on-close, or zero (the
2249
** default) to enable them, and negative to leave the setting unchanged.
2250
** The second parameter is a pointer to an integer
2251
** into which is written 0 or 1 to indicate whether checkpoints-on-close
2252
** have been disabled - 0 if they are not disabled, 1 if they are.
2253
** </dd>
2254
**
2255
** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
2256
** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
2257
** the [query planner stability guarantee] (QPSG).  When the QPSG is active,
2258
** a single SQL query statement will always use the same algorithm regardless
2259
** of values of [bound parameters].)^ The QPSG disables some query optimizations
2260
** that look at the values of bound parameters, which can make some queries
2261
** slower.  But the QPSG has the advantage of more predictable behavior.  With
2262
** the QPSG active, SQLite will always use the same query plan in the field as
2263
** was used during testing in the lab.
2264
** The first argument to this setting is an integer which is 0 to disable
2265
** the QPSG, positive to enable QPSG, or negative to leave the setting
2266
** unchanged. The second parameter is a pointer to an integer into which
2267
** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
2268
** following this call.
2269
** </dd>
2270
**
2271
** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
2272
** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not
2273
** include output for any operations performed by trigger programs. This
2274
** option is used to set or clear (the default) a flag that governs this
2275
** behavior. The first parameter passed to this operation is an integer -
2276
** positive to enable output for trigger programs, or zero to disable it,
2277
** or negative to leave the setting unchanged.
2278
** The second parameter is a pointer to an integer into which is written
2279
** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
2280
** it is not disabled, 1 if it is.
2281
** </dd>
2282
**
2283
** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt>
2284
** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
2285
** [VACUUM] in order to reset a database back to an empty database
2286
** with no schema and no content. The following process works even for
2287
** a badly corrupted database file:
2288
** <ol>
2289
** <li> If the database connection is newly opened, make sure it has read the
2290
**      database schema by preparing then discarding some query against the
2291
**      database, or calling sqlite3_table_column_metadata(), ignoring any
2292
**      errors.  This step is only necessary if the application desires to keep
2293
**      the database in WAL mode after the reset if it was in WAL mode before
2294
**      the reset.
2295
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
2296
** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
2297
** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
2298
** </ol>
2299
** Because resetting a database is destructive and irreversible, the
2300
** process requires the use of this obscure API and multiple steps to help
2301
** ensure that it does not happen by accident.
2302
**
2303
** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
2304
** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
2305
** "defensive" flag for a database connection.  When the defensive
2306
** flag is enabled, language features that allow ordinary SQL to
2307
** deliberately corrupt the database file are disabled.  The disabled
2308
** features include but are not limited to the following:
2309
** <ul>
2310
** <li> The [PRAGMA writable_schema=ON] statement.
2311
** <li> The [PRAGMA journal_mode=OFF] statement.
2312
** <li> Writes to the [sqlite_dbpage] virtual table.
2313
** <li> Direct writes to [shadow tables].
2314
** </ul>
2315
** </dd>
2316
**
2317
** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
2318
** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
2319
** "writable_schema" flag. This has the same effect and is logically equivalent
2320
** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
2321
** The first argument to this setting is an integer which is 0 to disable
2322
** the writable_schema, positive to enable writable_schema, or negative to
2323
** leave the setting unchanged. The second parameter is a pointer to an
2324
** integer into which is written 0 or 1 to indicate whether the writable_schema
2325
** is enabled or disabled following this call.
2326
** </dd>
2327
**
2328
** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]]
2329
** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt>
2330
** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates
2331
** the legacy behavior of the [ALTER TABLE RENAME] command such it
2332
** behaves as it did prior to [version 3.24.0] (2018-06-04).  See the
2333
** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for
2334
** additional information. This feature can also be turned on and off
2335
** using the [PRAGMA legacy_alter_table] statement.
2336
** </dd>
2337
**
2338
** [[SQLITE_DBCONFIG_DQS_DML]]
2339
** <dt>SQLITE_DBCONFIG_DQS_DML</td>
2340
** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
2341
** the legacy [double-quoted string literal] misfeature for DML statements
2342
** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
2343
** default value of this setting is determined by the [-DSQLITE_DQS]
2344
** compile-time option.
2345
** </dd>
2346
**
2347
** [[SQLITE_DBCONFIG_DQS_DDL]]
2348
** <dt>SQLITE_DBCONFIG_DQS_DDL</td>
2349
** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
2350
** the legacy [double-quoted string literal] misfeature for DDL statements,
2351
** such as CREATE TABLE and CREATE INDEX. The
2352
** default value of this setting is determined by the [-DSQLITE_DQS]
2353
** compile-time option.
2354
** </dd>
2355
**
2356
** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
2357
** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td>
2358
** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
2359
** assume that database schemas are untainted by malicious content.
2360
** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
2361
** takes additional defensive steps to protect the application from harm
2362
** including:
2363
** <ul>
2364
** <li> Prohibit the use of SQL functions inside triggers, views,
2365
** CHECK constraints, DEFAULT clauses, expression indexes,
2366
** partial indexes, or generated columns
2367
** unless those functions are tagged with [SQLITE_INNOCUOUS].
2368
** <li> Prohibit the use of virtual tables inside of triggers or views
2369
** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS].
2370
** </ul>
2371
** This setting defaults to "on" for legacy compatibility, however
2372
** all applications are advised to turn it off if possible. This setting
2373
** can also be controlled using the [PRAGMA trusted_schema] statement.
2374
** </dd>
2375
**
2376
** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
2377
** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td>
2378
** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
2379
** the legacy file format flag.  When activated, this flag causes all newly
2380
** created database file to have a schema format version number (the 4-byte
2381
** integer found at offset 44 into the database header) of 1.  This in turn
2382
** means that the resulting database file will be readable and writable by
2383
** any SQLite version back to 3.0.0 ([dateof:3.0.0]).  Without this setting,
2384
** newly created databases are generally not understandable by SQLite versions
2385
** prior to 3.3.0 ([dateof:3.3.0]).  As these words are written, there
2386
** is now scarcely any need to generated database files that are compatible
2387
** all the way back to version 3.0.0, and so this setting is of little
2388
** practical use, but is provided so that SQLite can continue to claim the
2389
** ability to generate new database files that are compatible with  version
2390
** 3.0.0.
2391
** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on,
2392
** the [VACUUM] command will fail with an obscure error when attempting to
2393
** process a table with generated columns and a descending index.  This is
2394
** not considered a bug since SQLite versions 3.3.0 and earlier do not support
2395
** either generated columns or decending indexes.
2396
** </dd>
2397
** </dl>
2398
*/
2399
#define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
2400
#define SQLITE_DBCONFIG_LOOKASIDE             1001 /* void* int int */
2401
#define SQLITE_DBCONFIG_ENABLE_FKEY           1002 /* int int* */
2402
#define SQLITE_DBCONFIG_ENABLE_TRIGGER        1003 /* int int* */
2403
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
2404
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
2405
#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE      1006 /* int int* */
2406
#define SQLITE_DBCONFIG_ENABLE_QPSG           1007 /* int int* */
2407
#define SQLITE_DBCONFIG_TRIGGER_EQP           1008 /* int int* */
2408
#define SQLITE_DBCONFIG_RESET_DATABASE        1009 /* int int* */
2409
#define SQLITE_DBCONFIG_DEFENSIVE             1010 /* int int* */
2410
#define SQLITE_DBCONFIG_WRITABLE_SCHEMA       1011 /* int int* */
2411
#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE    1012 /* int int* */
2412
#define SQLITE_DBCONFIG_DQS_DML               1013 /* int int* */
2413
#define SQLITE_DBCONFIG_DQS_DDL               1014 /* int int* */
2414
#define SQLITE_DBCONFIG_ENABLE_VIEW           1015 /* int int* */
2415
#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT    1016 /* int int* */
2416
#define SQLITE_DBCONFIG_TRUSTED_SCHEMA        1017 /* int int* */
2417
#define SQLITE_DBCONFIG_MAX                   1017 /* Largest DBCONFIG */
2418
2419
/*
2420
** CAPI3REF: Enable Or Disable Extended Result Codes
2421
** METHOD: sqlite3
2422
**
2423
** ^The sqlite3_extended_result_codes() routine enables or disables the
2424
** [extended result codes] feature of SQLite. ^The extended result
2425
** codes are disabled by default for historical compatibility.
2426
*/
2427
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
2428
2429
/*
2430
** CAPI3REF: Last Insert Rowid
2431
** METHOD: sqlite3
2432
**
2433
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
2434
** has a unique 64-bit signed
2435
** integer key called the [ROWID | "rowid"]. ^The rowid is always available
2436
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
2437
** names are not also used by explicitly declared columns. ^If
2438
** the table has a column of type [INTEGER PRIMARY KEY] then that column
2439
** is another alias for the rowid.
2440
**
2441
** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
2442
** the most recent successful [INSERT] into a rowid table or [virtual table]
2443
** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
2444
** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
2445
** on the database connection D, then sqlite3_last_insert_rowid(D) returns
2446
** zero.
2447
**
2448
** As well as being set automatically as rows are inserted into database
2449
** tables, the value returned by this function may be set explicitly by
2450
** [sqlite3_set_last_insert_rowid()]
2451
**
2452
** Some virtual table implementations may INSERT rows into rowid tables as
2453
** part of committing a transaction (e.g. to flush data accumulated in memory
2454
** to disk). In this case subsequent calls to this function return the rowid
2455
** associated with these internal INSERT operations, which leads to
2456
** unintuitive results. Virtual table implementations that do write to rowid
2457
** tables in this way can avoid this problem by restoring the original
2458
** rowid value using [sqlite3_set_last_insert_rowid()] before returning
2459
** control to the user.
2460
**
2461
** ^(If an [INSERT] occurs within a trigger then this routine will
2462
** return the [rowid] of the inserted row as long as the trigger is
2463
** running. Once the trigger program ends, the value returned
2464
** by this routine reverts to what it was before the trigger was fired.)^
2465
**
2466
** ^An [INSERT] that fails due to a constraint violation is not a
2467
** successful [INSERT] and does not change the value returned by this
2468
** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
2469
** and INSERT OR ABORT make no changes to the return value of this
2470
** routine when their insertion fails.  ^(When INSERT OR REPLACE
2471
** encounters a constraint violation, it does not fail.  The
2472
** INSERT continues to completion after deleting rows that caused
2473
** the constraint problem so INSERT OR REPLACE will always change
2474
** the return value of this interface.)^
2475
**
2476
** ^For the purposes of this routine, an [INSERT] is considered to
2477
** be successful even if it is subsequently rolled back.
2478
**
2479
** This function is accessible to SQL statements via the
2480
** [last_insert_rowid() SQL function].
2481
**
2482
** If a separate thread performs a new [INSERT] on the same
2483
** database connection while the [sqlite3_last_insert_rowid()]
2484
** function is running and thus changes the last insert [rowid],
2485
** then the value returned by [sqlite3_last_insert_rowid()] is
2486
** unpredictable and might not equal either the old or the new
2487
** last insert [rowid].
2488
*/
2489
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
2490
2491
/*
2492
** CAPI3REF: Set the Last Insert Rowid value.
2493
** METHOD: sqlite3
2494
**
2495
** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
2496
** set the value returned by calling sqlite3_last_insert_rowid(D) to R
2497
** without inserting a row into the database.
2498
*/
2499
SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
2500
2501
/*
2502
** CAPI3REF: Count The Number Of Rows Modified
2503
** METHOD: sqlite3
2504
**
2505
** ^These functions return the number of rows modified, inserted or
2506
** deleted by the most recently completed INSERT, UPDATE or DELETE
2507
** statement on the database connection specified by the only parameter.
2508
** The two functions are identical except for the type of the return value
2509
** and that if the number of rows modified by the most recent INSERT, UPDATE
2510
** or DELETE is greater than the maximum value supported by type "int", then
2511
** the return value of sqlite3_changes() is undefined. ^Executing any other
2512
** type of SQL statement does not modify the value returned by these functions.
2513
**
2514
** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
2515
** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
2516
** [foreign key actions] or [REPLACE] constraint resolution are not counted.
2517
**
2518
** Changes to a view that are intercepted by
2519
** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
2520
** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
2521
** DELETE statement run on a view is always zero. Only changes made to real
2522
** tables are counted.
2523
**
2524
** Things are more complicated if the sqlite3_changes() function is
2525
** executed while a trigger program is running. This may happen if the
2526
** program uses the [changes() SQL function], or if some other callback
2527
** function invokes sqlite3_changes() directly. Essentially:
2528
**
2529
** <ul>
2530
**   <li> ^(Before entering a trigger program the value returned by
2531
**        sqlite3_changes() function is saved. After the trigger program
2532
**        has finished, the original value is restored.)^
2533
**
2534
**   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
2535
**        statement sets the value returned by sqlite3_changes()
2536
**        upon completion as normal. Of course, this value will not include
2537
**        any changes performed by sub-triggers, as the sqlite3_changes()
2538
**        value will be saved and restored after each sub-trigger has run.)^
2539
** </ul>
2540
**
2541
** ^This means that if the changes() SQL function (or similar) is used
2542
** by the first INSERT, UPDATE or DELETE statement within a trigger, it
2543
** returns the value as set when the calling statement began executing.
2544
** ^If it is used by the second or subsequent such statement within a trigger
2545
** program, the value returned reflects the number of rows modified by the
2546
** previous INSERT, UPDATE or DELETE statement within the same trigger.
2547
**
2548
** If a separate thread makes changes on the same database connection
2549
** while [sqlite3_changes()] is running then the value returned
2550
** is unpredictable and not meaningful.
2551
**
2552
** See also:
2553
** <ul>
2554
** <li> the [sqlite3_total_changes()] interface
2555
** <li> the [count_changes pragma]
2556
** <li> the [changes() SQL function]
2557
** <li> the [data_version pragma]
2558
** </ul>
2559
*/
2560
SQLITE_API int sqlite3_changes(sqlite3*);
2561
SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*);
2562
2563
/*
2564
** CAPI3REF: Total Number Of Rows Modified
2565
** METHOD: sqlite3
2566
**
2567
** ^These functions return the total number of rows inserted, modified or
2568
** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
2569
** since the database connection was opened, including those executed as
2570
** part of trigger programs. The two functions are identical except for the
2571
** type of the return value and that if the number of rows modified by the
2572
** connection exceeds the maximum value supported by type "int", then
2573
** the return value of sqlite3_total_changes() is undefined. ^Executing
2574
** any other type of SQL statement does not affect the value returned by
2575
** sqlite3_total_changes().
2576
**
2577
** ^Changes made as part of [foreign key actions] are included in the
2578
** count, but those made as part of REPLACE constraint resolution are
2579
** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
2580
** are not counted.
2581
**
2582
** The [sqlite3_total_changes(D)] interface only reports the number
2583
** of rows that changed due to SQL statement run against database
2584
** connection D.  Any changes by other database connections are ignored.
2585
** To detect changes against a database file from other database
2586
** connections use the [PRAGMA data_version] command or the
2587
** [SQLITE_FCNTL_DATA_VERSION] [file control].
2588
**
2589
** If a separate thread makes changes on the same database connection
2590
** while [sqlite3_total_changes()] is running then the value
2591
** returned is unpredictable and not meaningful.
2592
**
2593
** See also:
2594
** <ul>
2595
** <li> the [sqlite3_changes()] interface
2596
** <li> the [count_changes pragma]
2597
** <li> the [changes() SQL function]
2598
** <li> the [data_version pragma]
2599
** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control]
2600
** </ul>
2601
*/
2602
SQLITE_API int sqlite3_total_changes(sqlite3*);
2603
SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*);
2604
2605
/*
2606
** CAPI3REF: Interrupt A Long-Running Query
2607
** METHOD: sqlite3
2608
**
2609
** ^This function causes any pending database operation to abort and
2610
** return at its earliest opportunity. This routine is typically
2611
** called in response to a user action such as pressing "Cancel"
2612
** or Ctrl-C where the user wants a long query operation to halt
2613
** immediately.
2614
**
2615
** ^It is safe to call this routine from a thread different from the
2616
** thread that is currently running the database operation.  But it
2617
** is not safe to call this routine with a [database connection] that
2618
** is closed or might close before sqlite3_interrupt() returns.
2619
**
2620
** ^If an SQL operation is very nearly finished at the time when
2621
** sqlite3_interrupt() is called, then it might not have an opportunity
2622
** to be interrupted and might continue to completion.
2623
**
2624
** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
2625
** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
2626
** that is inside an explicit transaction, then the entire transaction
2627
** will be rolled back automatically.
2628
**
2629
** ^The sqlite3_interrupt(D) call is in effect until all currently running
2630
** SQL statements on [database connection] D complete.  ^Any new SQL statements
2631
** that are started after the sqlite3_interrupt() call and before the
2632
** running statement count reaches zero are interrupted as if they had been
2633
** running prior to the sqlite3_interrupt() call.  ^New SQL statements
2634
** that are started after the running statement count reaches zero are
2635
** not effected by the sqlite3_interrupt().
2636
** ^A call to sqlite3_interrupt(D) that occurs when there are no running
2637
** SQL statements is a no-op and has no effect on SQL statements
2638
** that are started after the sqlite3_interrupt() call returns.
2639
*/
2640
SQLITE_API void sqlite3_interrupt(sqlite3*);
2641
2642
/*
2643
** CAPI3REF: Determine If An SQL Statement Is Complete
2644
**
2645
** These routines are useful during command-line input to determine if the
2646
** currently entered text seems to form a complete SQL statement or
2647
** if additional input is needed before sending the text into
2648
** SQLite for parsing.  ^These routines return 1 if the input string
2649
** appears to be a complete SQL statement.  ^A statement is judged to be
2650
** complete if it ends with a semicolon token and is not a prefix of a
2651
** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
2652
** string literals or quoted identifier names or comments are not
2653
** independent tokens (they are part of the token in which they are
2654
** embedded) and thus do not count as a statement terminator.  ^Whitespace
2655
** and comments that follow the final semicolon are ignored.
2656
**
2657
** ^These routines return 0 if the statement is incomplete.  ^If a
2658
** memory allocation fails, then SQLITE_NOMEM is returned.
2659
**
2660
** ^These routines do not parse the SQL statements thus
2661
** will not detect syntactically incorrect SQL.
2662
**
2663
** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
2664
** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
2665
** automatically by sqlite3_complete16().  If that initialization fails,
2666
** then the return value from sqlite3_complete16() will be non-zero
2667
** regardless of whether or not the input SQL is complete.)^
2668
**
2669
** The input to [sqlite3_complete()] must be a zero-terminated
2670
** UTF-8 string.
2671
**
2672
** The input to [sqlite3_complete16()] must be a zero-terminated
2673
** UTF-16 string in native byte order.
2674
*/
2675
SQLITE_API int sqlite3_complete(const char *sql);
2676
SQLITE_API int sqlite3_complete16(const void *sql);
2677
2678
/*
2679
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
2680
** KEYWORDS: {busy-handler callback} {busy handler}
2681
** METHOD: sqlite3
2682
**
2683
** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
2684
** that might be invoked with argument P whenever
2685
** an attempt is made to access a database table associated with
2686
** [database connection] D when another thread
2687
** or process has the table locked.
2688
** The sqlite3_busy_handler() interface is used to implement
2689
** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
2690
**
2691
** ^If the busy callback is NULL, then [SQLITE_BUSY]
2692
** is returned immediately upon encountering the lock.  ^If the busy callback
2693
** is not NULL, then the callback might be invoked with two arguments.
2694
**
2695
** ^The first argument to the busy handler is a copy of the void* pointer which
2696
** is the third argument to sqlite3_busy_handler().  ^The second argument to
2697
** the busy handler callback is the number of times that the busy handler has
2698
** been invoked previously for the same locking event.  ^If the
2699
** busy callback returns 0, then no additional attempts are made to
2700
** access the database and [SQLITE_BUSY] is returned
2701
** to the application.
2702
** ^If the callback returns non-zero, then another attempt
2703
** is made to access the database and the cycle repeats.
2704
**
2705
** The presence of a busy handler does not guarantee that it will be invoked
2706
** when there is lock contention. ^If SQLite determines that invoking the busy
2707
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
2708
** to the application instead of invoking the
2709
** busy handler.
2710
** Consider a scenario where one process is holding a read lock that
2711
** it is trying to promote to a reserved lock and
2712
** a second process is holding a reserved lock that it is trying
2713
** to promote to an exclusive lock.  The first process cannot proceed
2714
** because it is blocked by the second and the second process cannot
2715
** proceed because it is blocked by the first.  If both processes
2716
** invoke the busy handlers, neither will make any progress.  Therefore,
2717
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
2718
** will induce the first process to release its read lock and allow
2719
** the second process to proceed.
2720
**
2721
** ^The default busy callback is NULL.
2722
**
2723
** ^(There can only be a single busy handler defined for each
2724
** [database connection].  Setting a new busy handler clears any
2725
** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
2726
** or evaluating [PRAGMA busy_timeout=N] will change the
2727
** busy handler and thus clear any previously set busy handler.
2728
**
2729
** The busy callback should not take any actions which modify the
2730
** database connection that invoked the busy handler.  In other words,
2731
** the busy handler is not reentrant.  Any such actions
2732
** result in undefined behavior.
2733
**
2734
** A busy handler must not close the database connection
2735
** or [prepared statement] that invoked the busy handler.
2736
*/
2737
SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
2738
2739
/*
2740
** CAPI3REF: Set A Busy Timeout
2741
** METHOD: sqlite3
2742
**
2743
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
2744
** for a specified amount of time when a table is locked.  ^The handler
2745
** will sleep multiple times until at least "ms" milliseconds of sleeping
2746
** have accumulated.  ^After at least "ms" milliseconds of sleeping,
2747
** the handler returns 0 which causes [sqlite3_step()] to return
2748
** [SQLITE_BUSY].
2749
**
2750
** ^Calling this routine with an argument less than or equal to zero
2751
** turns off all busy handlers.
2752
**
2753
** ^(There can only be a single busy handler for a particular
2754
** [database connection] at any given moment.  If another busy handler
2755
** was defined  (using [sqlite3_busy_handler()]) prior to calling
2756
** this routine, that other busy handler is cleared.)^
2757
**
2758
** See also:  [PRAGMA busy_timeout]
2759
*/
2760
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
2761
2762
/*
2763
** CAPI3REF: Convenience Routines For Running Queries
2764
** METHOD: sqlite3
2765
**
2766
** This is a legacy interface that is preserved for backwards compatibility.
2767
** Use of this interface is not recommended.
2768
**
2769
** Definition: A <b>result table</b> is memory data structure created by the
2770
** [sqlite3_get_table()] interface.  A result table records the
2771
** complete query results from one or more queries.
2772
**
2773
** The table conceptually has a number of rows and columns.  But
2774
** these numbers are not part of the result table itself.  These
2775
** numbers are obtained separately.  Let N be the number of rows
2776
** and M be the number of columns.
2777
**
2778
** A result table is an array of pointers to zero-terminated UTF-8 strings.
2779
** There are (N+1)*M elements in the array.  The first M pointers point
2780
** to zero-terminated strings that  contain the names of the columns.
2781
** The remaining entries all point to query results.  NULL values result
2782
** in NULL pointers.  All other values are in their UTF-8 zero-terminated
2783
** string representation as returned by [sqlite3_column_text()].
2784
**
2785
** A result table might consist of one or more memory allocations.
2786
** It is not safe to pass a result table directly to [sqlite3_free()].
2787
** A result table should be deallocated using [sqlite3_free_table()].
2788
**
2789
** ^(As an example of the result table format, suppose a query result
2790
** is as follows:
2791
**
2792
** <blockquote><pre>
2793
**        Name        | Age
2794
**        -----------------------
2795
**        Alice       | 43
2796
**        Bob         | 28
2797
**        Cindy       | 21
2798
** </pre></blockquote>
2799
**
2800
** There are two columns (M==2) and three rows (N==3).  Thus the
2801
** result table has 8 entries.  Suppose the result table is stored
2802
** in an array named azResult.  Then azResult holds this content:
2803
**
2804
** <blockquote><pre>
2805
**        azResult&#91;0] = "Name";
2806
**        azResult&#91;1] = "Age";
2807
**        azResult&#91;2] = "Alice";
2808
**        azResult&#91;3] = "43";
2809
**        azResult&#91;4] = "Bob";
2810
**        azResult&#91;5] = "28";
2811
**        azResult&#91;6] = "Cindy";
2812
**        azResult&#91;7] = "21";
2813
** </pre></blockquote>)^
2814
**
2815
** ^The sqlite3_get_table() function evaluates one or more
2816
** semicolon-separated SQL statements in the zero-terminated UTF-8
2817
** string of its 2nd parameter and returns a result table to the
2818
** pointer given in its 3rd parameter.
2819
**
2820
** After the application has finished with the result from sqlite3_get_table(),
2821
** it must pass the result table pointer to sqlite3_free_table() in order to
2822
** release the memory that was malloced.  Because of the way the
2823
** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
2824
** function must not try to call [sqlite3_free()] directly.  Only
2825
** [sqlite3_free_table()] is able to release the memory properly and safely.
2826
**
2827
** The sqlite3_get_table() interface is implemented as a wrapper around
2828
** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
2829
** to any internal data structures of SQLite.  It uses only the public
2830
** interface defined here.  As a consequence, errors that occur in the
2831
** wrapper layer outside of the internal [sqlite3_exec()] call are not
2832
** reflected in subsequent calls to [sqlite3_errcode()] or
2833
** [sqlite3_errmsg()].
2834
*/
2835
SQLITE_API int sqlite3_get_table(
2836
  sqlite3 *db,          /* An open database */
2837
  const char *zSql,     /* SQL to be evaluated */
2838
  char ***pazResult,    /* Results of the query */
2839
  int *pnRow,           /* Number of result rows written here */
2840
  int *pnColumn,        /* Number of result columns written here */
2841
  char **pzErrmsg       /* Error msg written here */
2842
);
2843
SQLITE_API void sqlite3_free_table(char **result);
2844
2845
/*
2846
** CAPI3REF: Formatted String Printing Functions
2847
**
2848
** These routines are work-alikes of the "printf()" family of functions
2849
** from the standard C library.
2850
** These routines understand most of the common formatting options from
2851
** the standard library printf()
2852
** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
2853
** See the [built-in printf()] documentation for details.
2854
**
2855
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
2856
** results into memory obtained from [sqlite3_malloc64()].
2857
** The strings returned by these two routines should be
2858
** released by [sqlite3_free()].  ^Both routines return a
2859
** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
2860
** memory to hold the resulting string.
2861
**
2862
** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
2863
** the standard C library.  The result is written into the
2864
** buffer supplied as the second parameter whose size is given by
2865
** the first parameter. Note that the order of the
2866
** first two parameters is reversed from snprintf().)^  This is an
2867
** historical accident that cannot be fixed without breaking
2868
** backwards compatibility.  ^(Note also that sqlite3_snprintf()
2869
** returns a pointer to its buffer instead of the number of
2870
** characters actually written into the buffer.)^  We admit that
2871
** the number of characters written would be a more useful return
2872
** value but we cannot change the implementation of sqlite3_snprintf()
2873
** now without breaking compatibility.
2874
**
2875
** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
2876
** guarantees that the buffer is always zero-terminated.  ^The first
2877
** parameter "n" is the total size of the buffer, including space for
2878
** the zero terminator.  So the longest string that can be completely
2879
** written will be n-1 characters.
2880
**
2881
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
2882
**
2883
** See also:  [built-in printf()], [printf() SQL function]
2884
*/
2885
SQLITE_API char *sqlite3_mprintf(const char*,...);
2886
SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
2887
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
2888
SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
2889
2890
/*
2891
** CAPI3REF: Memory Allocation Subsystem
2892
**
2893
** The SQLite core uses these three routines for all of its own
2894
** internal memory allocation needs. "Core" in the previous sentence
2895
** does not include operating-system specific [VFS] implementation.  The
2896
** Windows VFS uses native malloc() and free() for some operations.
2897
**
2898
** ^The sqlite3_malloc() routine returns a pointer to a block
2899
** of memory at least N bytes in length, where N is the parameter.
2900
** ^If sqlite3_malloc() is unable to obtain sufficient free
2901
** memory, it returns a NULL pointer.  ^If the parameter N to
2902
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
2903
** a NULL pointer.
2904
**
2905
** ^The sqlite3_malloc64(N) routine works just like
2906
** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
2907
** of a signed 32-bit integer.
2908
**
2909
** ^Calling sqlite3_free() with a pointer previously returned
2910
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
2911
** that it might be reused.  ^The sqlite3_free() routine is
2912
** a no-op if is called with a NULL pointer.  Passing a NULL pointer
2913
** to sqlite3_free() is harmless.  After being freed, memory
2914
** should neither be read nor written.  Even reading previously freed
2915
** memory might result in a segmentation fault or other severe error.
2916
** Memory corruption, a segmentation fault, or other severe error
2917
** might result if sqlite3_free() is called with a non-NULL pointer that
2918
** was not obtained from sqlite3_malloc() or sqlite3_realloc().
2919
**
2920
** ^The sqlite3_realloc(X,N) interface attempts to resize a
2921
** prior memory allocation X to be at least N bytes.
2922
** ^If the X parameter to sqlite3_realloc(X,N)
2923
** is a NULL pointer then its behavior is identical to calling
2924
** sqlite3_malloc(N).
2925
** ^If the N parameter to sqlite3_realloc(X,N) is zero or
2926
** negative then the behavior is exactly the same as calling
2927
** sqlite3_free(X).
2928
** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
2929
** of at least N bytes in size or NULL if insufficient memory is available.
2930
** ^If M is the size of the prior allocation, then min(N,M) bytes
2931
** of the prior allocation are copied into the beginning of buffer returned
2932
** by sqlite3_realloc(X,N) and the prior allocation is freed.
2933
** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
2934
** prior allocation is not freed.
2935
**
2936
** ^The sqlite3_realloc64(X,N) interfaces works the same as
2937
** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
2938
** of a 32-bit signed integer.
2939
**
2940
** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
2941
** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
2942
** sqlite3_msize(X) returns the size of that memory allocation in bytes.
2943
** ^The value returned by sqlite3_msize(X) might be larger than the number
2944
** of bytes requested when X was allocated.  ^If X is a NULL pointer then
2945
** sqlite3_msize(X) returns zero.  If X points to something that is not
2946
** the beginning of memory allocation, or if it points to a formerly
2947
** valid memory allocation that has now been freed, then the behavior
2948
** of sqlite3_msize(X) is undefined and possibly harmful.
2949
**
2950
** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
2951
** sqlite3_malloc64(), and sqlite3_realloc64()
2952
** is always aligned to at least an 8 byte boundary, or to a
2953
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
2954
** option is used.
2955
**
2956
** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
2957
** must be either NULL or else pointers obtained from a prior
2958
** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
2959
** not yet been released.
2960
**
2961
** The application must not read or write any part of
2962
** a block of memory after it has been released using
2963
** [sqlite3_free()] or [sqlite3_realloc()].
2964
*/
2965
SQLITE_API void *sqlite3_malloc(int);
2966
SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
2967
SQLITE_API void *sqlite3_realloc(void*, int);
2968
SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
2969
SQLITE_API void sqlite3_free(void*);
2970
SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
2971
2972
/*
2973
** CAPI3REF: Memory Allocator Statistics
2974
**
2975
** SQLite provides these two interfaces for reporting on the status
2976
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
2977
** routines, which form the built-in memory allocation subsystem.
2978
**
2979
** ^The [sqlite3_memory_used()] routine returns the number of bytes
2980
** of memory currently outstanding (malloced but not freed).
2981
** ^The [sqlite3_memory_highwater()] routine returns the maximum
2982
** value of [sqlite3_memory_used()] since the high-water mark
2983
** was last reset.  ^The values returned by [sqlite3_memory_used()] and
2984
** [sqlite3_memory_highwater()] include any overhead
2985
** added by SQLite in its implementation of [sqlite3_malloc()],
2986
** but not overhead added by the any underlying system library
2987
** routines that [sqlite3_malloc()] may call.
2988
**
2989
** ^The memory high-water mark is reset to the current value of
2990
** [sqlite3_memory_used()] if and only if the parameter to
2991
** [sqlite3_memory_highwater()] is true.  ^The value returned
2992
** by [sqlite3_memory_highwater(1)] is the high-water mark
2993
** prior to the reset.
2994
*/
2995
SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
2996
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
2997
2998
/*
2999
** CAPI3REF: Pseudo-Random Number Generator
3000
**
3001
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
3002
** select random [ROWID | ROWIDs] when inserting new records into a table that
3003
** already uses the largest possible [ROWID].  The PRNG is also used for
3004
** the built-in random() and randomblob() SQL functions.  This interface allows
3005
** applications to access the same PRNG for other purposes.
3006
**
3007
** ^A call to this routine stores N bytes of randomness into buffer P.
3008
** ^The P parameter can be a NULL pointer.
3009
**
3010
** ^If this routine has not been previously called or if the previous
3011
** call had N less than one or a NULL pointer for P, then the PRNG is
3012
** seeded using randomness obtained from the xRandomness method of
3013
** the default [sqlite3_vfs] object.
3014
** ^If the previous call to this routine had an N of 1 or more and a
3015
** non-NULL P then the pseudo-randomness is generated
3016
** internally and without recourse to the [sqlite3_vfs] xRandomness
3017
** method.
3018
*/
3019
SQLITE_API void sqlite3_randomness(int N, void *P);
3020
3021
/*
3022
** CAPI3REF: Compile-Time Authorization Callbacks
3023
** METHOD: sqlite3
3024
** KEYWORDS: {authorizer callback}
3025
**
3026
** ^This routine registers an authorizer callback with a particular
3027
** [database connection], supplied in the first argument.
3028
** ^The authorizer callback is invoked as SQL statements are being compiled
3029
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
3030
** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
3031
** and [sqlite3_prepare16_v3()].  ^At various
3032
** points during the compilation process, as logic is being created
3033
** to perform various actions, the authorizer callback is invoked to
3034
** see if those actions are allowed.  ^The authorizer callback should
3035
** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
3036
** specific action but allow the SQL statement to continue to be
3037
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
3038
** rejected with an error.  ^If the authorizer callback returns
3039
** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
3040
** then the [sqlite3_prepare_v2()] or equivalent call that triggered
3041
** the authorizer will fail with an error message.
3042
**
3043
** When the callback returns [SQLITE_OK], that means the operation
3044
** requested is ok.  ^When the callback returns [SQLITE_DENY], the
3045
** [sqlite3_prepare_v2()] or equivalent call that triggered the
3046
** authorizer will fail with an error message explaining that
3047
** access is denied.
3048
**
3049
** ^The first parameter to the authorizer callback is a copy of the third
3050
** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
3051
** to the callback is an integer [SQLITE_COPY | action code] that specifies
3052
** the particular action to be authorized. ^The third through sixth parameters
3053
** to the callback are either NULL pointers or zero-terminated strings
3054
** that contain additional details about the action to be authorized.
3055
** Applications must always be prepared to encounter a NULL pointer in any
3056
** of the third through the sixth parameters of the authorization callback.
3057
**
3058
** ^If the action code is [SQLITE_READ]
3059
** and the callback returns [SQLITE_IGNORE] then the
3060
** [prepared statement] statement is constructed to substitute
3061
** a NULL value in place of the table column that would have
3062
** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
3063
** return can be used to deny an untrusted user access to individual
3064
** columns of a table.
3065
** ^When a table is referenced by a [SELECT] but no column values are
3066
** extracted from that table (for example in a query like
3067
** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
3068
** is invoked once for that table with a column name that is an empty string.
3069
** ^If the action code is [SQLITE_DELETE] and the callback returns
3070
** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
3071
** [truncate optimization] is disabled and all rows are deleted individually.
3072
**
3073
** An authorizer is used when [sqlite3_prepare | preparing]
3074
** SQL statements from an untrusted source, to ensure that the SQL statements
3075
** do not try to access data they are not allowed to see, or that they do not
3076
** try to execute malicious statements that damage the database.  For
3077
** example, an application may allow a user to enter arbitrary
3078
** SQL queries for evaluation by a database.  But the application does
3079
** not want the user to be able to make arbitrary changes to the
3080
** database.  An authorizer could then be put in place while the
3081
** user-entered SQL is being [sqlite3_prepare | prepared] that
3082
** disallows everything except [SELECT] statements.
3083
**
3084
** Applications that need to process SQL from untrusted sources
3085
** might also consider lowering resource limits using [sqlite3_limit()]
3086
** and limiting database size using the [max_page_count] [PRAGMA]
3087
** in addition to using an authorizer.
3088
**
3089
** ^(Only a single authorizer can be in place on a database connection
3090
** at a time.  Each call to sqlite3_set_authorizer overrides the
3091
** previous call.)^  ^Disable the authorizer by installing a NULL callback.
3092
** The authorizer is disabled by default.
3093
**
3094
** The authorizer callback must not do anything that will modify
3095
** the database connection that invoked the authorizer callback.
3096
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3097
** database connections for the meaning of "modify" in this paragraph.
3098
**
3099
** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
3100
** statement might be re-prepared during [sqlite3_step()] due to a
3101
** schema change.  Hence, the application should ensure that the
3102
** correct authorizer callback remains in place during the [sqlite3_step()].
3103
**
3104
** ^Note that the authorizer callback is invoked only during
3105
** [sqlite3_prepare()] or its variants.  Authorization is not
3106
** performed during statement evaluation in [sqlite3_step()], unless
3107
** as stated in the previous paragraph, sqlite3_step() invokes
3108
** sqlite3_prepare_v2() to reprepare a statement after a schema change.
3109
*/
3110
SQLITE_API int sqlite3_set_authorizer(
3111
  sqlite3*,
3112
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
3113
  void *pUserData
3114
);
3115
3116
/*
3117
** CAPI3REF: Authorizer Return Codes
3118
**
3119
** The [sqlite3_set_authorizer | authorizer callback function] must
3120
** return either [SQLITE_OK] or one of these two constants in order
3121
** to signal SQLite whether or not the action is permitted.  See the
3122
** [sqlite3_set_authorizer | authorizer documentation] for additional
3123
** information.
3124
**
3125
** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
3126
** returned from the [sqlite3_vtab_on_conflict()] interface.
3127
*/
3128
#define SQLITE_DENY   1   /* Abort the SQL statement with an error */
3129
#define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
3130
3131
/*
3132
** CAPI3REF: Authorizer Action Codes
3133
**
3134
** The [sqlite3_set_authorizer()] interface registers a callback function
3135
** that is invoked to authorize certain SQL statement actions.  The
3136
** second parameter to the callback is an integer code that specifies
3137
** what action is being authorized.  These are the integer action codes that
3138
** the authorizer callback may be passed.
3139
**
3140
** These action code values signify what kind of operation is to be
3141
** authorized.  The 3rd and 4th parameters to the authorization
3142
** callback function will be parameters or NULL depending on which of these
3143
** codes is used as the second parameter.  ^(The 5th parameter to the
3144
** authorizer callback is the name of the database ("main", "temp",
3145
** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
3146
** is the name of the inner-most trigger or view that is responsible for
3147
** the access attempt or NULL if this access attempt is directly from
3148
** top-level SQL code.
3149
*/
3150
/******************************************* 3rd ************ 4th ***********/
3151
#define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
3152
#define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
3153
#define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
3154
#define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
3155
#define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
3156
#define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
3157
#define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
3158
#define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
3159
#define SQLITE_DELETE                9   /* Table Name      NULL            */
3160
#define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
3161
#define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
3162
#define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
3163
#define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
3164
#define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
3165
#define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
3166
#define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
3167
#define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
3168
#define SQLITE_INSERT               18   /* Table Name      NULL            */
3169
#define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
3170
#define SQLITE_READ                 20   /* Table Name      Column Name     */
3171
#define SQLITE_SELECT               21   /* NULL            NULL            */
3172
#define SQLITE_TRANSACTION          22   /* Operation       NULL            */
3173
#define SQLITE_UPDATE               23   /* Table Name      Column Name     */
3174
#define SQLITE_ATTACH               24   /* Filename        NULL            */
3175
#define SQLITE_DETACH               25   /* Database Name   NULL            */
3176
#define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
3177
#define SQLITE_REINDEX              27   /* Index Name      NULL            */
3178
#define SQLITE_ANALYZE              28   /* Table Name      NULL            */
3179
#define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
3180
#define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
3181
#define SQLITE_FUNCTION             31   /* NULL            Function Name   */
3182
#define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
3183
#define SQLITE_COPY                  0   /* No longer used */
3184
#define SQLITE_RECURSIVE            33   /* NULL            NULL            */
3185
3186
/*
3187
** CAPI3REF: Tracing And Profiling Functions
3188
** METHOD: sqlite3
3189
**
3190
** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
3191
** instead of the routines described here.
3192
**
3193
** These routines register callback functions that can be used for
3194
** tracing and profiling the execution of SQL statements.
3195
**
3196
** ^The callback function registered by sqlite3_trace() is invoked at
3197
** various times when an SQL statement is being run by [sqlite3_step()].
3198
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
3199
** SQL statement text as the statement first begins executing.
3200
** ^(Additional sqlite3_trace() callbacks might occur
3201
** as each triggered subprogram is entered.  The callbacks for triggers
3202
** contain a UTF-8 SQL comment that identifies the trigger.)^
3203
**
3204
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
3205
** the length of [bound parameter] expansion in the output of sqlite3_trace().
3206
**
3207
** ^The callback function registered by sqlite3_profile() is invoked
3208
** as each SQL statement finishes.  ^The profile callback contains
3209
** the original statement text and an estimate of wall-clock time
3210
** of how long that statement took to run.  ^The profile callback
3211
** time is in units of nanoseconds, however the current implementation
3212
** is only capable of millisecond resolution so the six least significant
3213
** digits in the time are meaningless.  Future versions of SQLite
3214
** might provide greater resolution on the profiler callback.  Invoking
3215
** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the
3216
** profile callback.
3217
*/
3218
SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
3219
   void(*xTrace)(void*,const char*), void*);
3220
SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
3221
   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
3222
3223
/*
3224
** CAPI3REF: SQL Trace Event Codes
3225
** KEYWORDS: SQLITE_TRACE
3226
**
3227
** These constants identify classes of events that can be monitored
3228
** using the [sqlite3_trace_v2()] tracing logic.  The M argument
3229
** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
3230
** the following constants.  ^The first argument to the trace callback
3231
** is one of the following constants.
3232
**
3233
** New tracing constants may be added in future releases.
3234
**
3235
** ^A trace callback has four arguments: xCallback(T,C,P,X).
3236
** ^The T argument is one of the integer type codes above.
3237
** ^The C argument is a copy of the context pointer passed in as the
3238
** fourth argument to [sqlite3_trace_v2()].
3239
** The P and X arguments are pointers whose meanings depend on T.
3240
**
3241
** <dl>
3242
** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
3243
** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
3244
** first begins running and possibly at other times during the
3245
** execution of the prepared statement, such as at the start of each
3246
** trigger subprogram. ^The P argument is a pointer to the
3247
** [prepared statement]. ^The X argument is a pointer to a string which
3248
** is the unexpanded SQL text of the prepared statement or an SQL comment
3249
** that indicates the invocation of a trigger.  ^The callback can compute
3250
** the same text that would have been returned by the legacy [sqlite3_trace()]
3251
** interface by using the X argument when X begins with "--" and invoking
3252
** [sqlite3_expanded_sql(P)] otherwise.
3253
**
3254
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
3255
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
3256
** information as is provided by the [sqlite3_profile()] callback.
3257
** ^The P argument is a pointer to the [prepared statement] and the
3258
** X argument points to a 64-bit integer which is the estimated of
3259
** the number of nanosecond that the prepared statement took to run.
3260
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
3261
**
3262
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
3263
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
3264
** statement generates a single row of result.
3265
** ^The P argument is a pointer to the [prepared statement] and the
3266
** X argument is unused.
3267
**
3268
** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
3269
** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
3270
** connection closes.
3271
** ^The P argument is a pointer to the [database connection] object
3272
** and the X argument is unused.
3273
** </dl>
3274
*/
3275
#define SQLITE_TRACE_STMT       0x01
3276
#define SQLITE_TRACE_PROFILE    0x02
3277
#define SQLITE_TRACE_ROW        0x04
3278
#define SQLITE_TRACE_CLOSE      0x08
3279
3280
/*
3281
** CAPI3REF: SQL Trace Hook
3282
** METHOD: sqlite3
3283
**
3284
** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
3285
** function X against [database connection] D, using property mask M
3286
** and context pointer P.  ^If the X callback is
3287
** NULL or if the M mask is zero, then tracing is disabled.  The
3288
** M argument should be the bitwise OR-ed combination of
3289
** zero or more [SQLITE_TRACE] constants.
3290
**
3291
** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides
3292
** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().
3293
**
3294
** ^The X callback is invoked whenever any of the events identified by
3295
** mask M occur.  ^The integer return value from the callback is currently
3296
** ignored, though this may change in future releases.  Callback
3297
** implementations should return zero to ensure future compatibility.
3298
**
3299
** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
3300
** ^The T argument is one of the [SQLITE_TRACE]
3301
** constants to indicate why the callback was invoked.
3302
** ^The C argument is a copy of the context pointer.
3303
** The P and X arguments are pointers whose meanings depend on T.
3304
**
3305
** The sqlite3_trace_v2() interface is intended to replace the legacy
3306
** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
3307
** are deprecated.
3308
*/
3309
SQLITE_API int sqlite3_trace_v2(
3310
  sqlite3*,
3311
  unsigned uMask,
3312
  int(*xCallback)(unsigned,void*,void*,void*),
3313
  void *pCtx
3314
);
3315
3316
/*
3317
** CAPI3REF: Query Progress Callbacks
3318
** METHOD: sqlite3
3319
**
3320
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
3321
** function X to be invoked periodically during long running calls to
3322
** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
3323
** database connection D.  An example use for this
3324
** interface is to keep a GUI updated during a large query.
3325
**
3326
** ^The parameter P is passed through as the only parameter to the
3327
** callback function X.  ^The parameter N is the approximate number of
3328
** [virtual machine instructions] that are evaluated between successive
3329
** invocations of the callback X.  ^If N is less than one then the progress
3330
** handler is disabled.
3331
**
3332
** ^Only a single progress handler may be defined at one time per
3333
** [database connection]; setting a new progress handler cancels the
3334
** old one.  ^Setting parameter X to NULL disables the progress handler.
3335
** ^The progress handler is also disabled by setting N to a value less
3336
** than 1.
3337
**
3338
** ^If the progress callback returns non-zero, the operation is
3339
** interrupted.  This feature can be used to implement a
3340
** "Cancel" button on a GUI progress dialog box.
3341
**
3342
** The progress handler callback must not do anything that will modify
3343
** the database connection that invoked the progress handler.
3344
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3345
** database connections for the meaning of "modify" in this paragraph.
3346
**
3347
*/
3348
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
3349
3350
/*
3351
** CAPI3REF: Opening A New Database Connection
3352
** CONSTRUCTOR: sqlite3
3353
**
3354
** ^These routines open an SQLite database file as specified by the
3355
** filename argument. ^The filename argument is interpreted as UTF-8 for
3356
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
3357
** order for sqlite3_open16(). ^(A [database connection] handle is usually
3358
** returned in *ppDb, even if an error occurs.  The only exception is that
3359
** if SQLite is unable to allocate memory to hold the [sqlite3] object,
3360
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
3361
** object.)^ ^(If the database is opened (and/or created) successfully, then
3362
** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
3363
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
3364
** an English language description of the error following a failure of any
3365
** of the sqlite3_open() routines.
3366
**
3367
** ^The default encoding will be UTF-8 for databases created using
3368
** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
3369
** created using sqlite3_open16() will be UTF-16 in the native byte order.
3370
**
3371
** Whether or not an error occurs when it is opened, resources
3372
** associated with the [database connection] handle should be released by
3373
** passing it to [sqlite3_close()] when it is no longer required.
3374
**
3375
** The sqlite3_open_v2() interface works like sqlite3_open()
3376
** except that it accepts two additional parameters for additional control
3377
** over the new database connection.  ^(The flags parameter to
3378
** sqlite3_open_v2() must include, at a minimum, one of the following
3379
** three flag combinations:)^
3380
**
3381
** <dl>
3382
** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
3383
** <dd>The database is opened in read-only mode.  If the database does not
3384
** already exist, an error is returned.</dd>)^
3385
**
3386
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
3387
** <dd>The database is opened for reading and writing if possible, or reading
3388
** only if the file is write protected by the operating system.  In either
3389
** case the database must already exist, otherwise an error is returned.</dd>)^
3390
**
3391
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
3392
** <dd>The database is opened for reading and writing, and is created if
3393
** it does not already exist. This is the behavior that is always used for
3394
** sqlite3_open() and sqlite3_open16().</dd>)^
3395
** </dl>
3396
**
3397
** In addition to the required flags, the following optional flags are
3398
** also supported:
3399
**
3400
** <dl>
3401
** ^(<dt>[SQLITE_OPEN_URI]</dt>
3402
** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^
3403
**
3404
** ^(<dt>[SQLITE_OPEN_MEMORY]</dt>
3405
** <dd>The database will be opened as an in-memory database.  The database
3406
** is named by the "filename" argument for the purposes of cache-sharing,
3407
** if shared cache mode is enabled, but the "filename" is otherwise ignored.
3408
** </dd>)^
3409
**
3410
** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt>
3411
** <dd>The new database connection will use the "multi-thread"
3412
** [threading mode].)^  This means that separate threads are allowed
3413
** to use SQLite at the same time, as long as each thread is using
3414
** a different [database connection].
3415
**
3416
** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt>
3417
** <dd>The new database connection will use the "serialized"
3418
** [threading mode].)^  This means the multiple threads can safely
3419
** attempt to use the same database connection at the same time.
3420
** (Mutexes will block any actual concurrency, but in this mode
3421
** there is no harm in trying.)
3422
**
3423
** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
3424
** <dd>The database is opened [shared cache] enabled, overriding
3425
** the default shared cache setting provided by
3426
** [sqlite3_enable_shared_cache()].)^
3427
**
3428
** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
3429
** <dd>The database is opened [shared cache] disabled, overriding
3430
** the default shared cache setting provided by
3431
** [sqlite3_enable_shared_cache()].)^
3432
**
3433
** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt>
3434
** <dd>The database connection comes up in "extended result code mode".
3435
** In other words, the database behaves has if
3436
** [sqlite3_extended_result_codes(db,1)] where called on the database
3437
** connection as soon as the connection is created. In addition to setting
3438
** the extended result code mode, this flag also causes [sqlite3_open_v2()]
3439
** to return an extended result code.</dd>
3440
**
3441
** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
3442
** <dd>The database filename is not allowed to be a symbolic link</dd>
3443
** </dl>)^
3444
**
3445
** If the 3rd parameter to sqlite3_open_v2() is not one of the
3446
** required combinations shown above optionally combined with other
3447
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
3448
** then the behavior is undefined.  Historic versions of SQLite
3449
** have silently ignored surplus bits in the flags parameter to
3450
** sqlite3_open_v2(), however that behavior might not be carried through
3451
** into future versions of SQLite and so applications should not rely
3452
** upon it.  Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op
3453
** for sqlite3_open_v2().  The SQLITE_OPEN_EXCLUSIVE does *not* cause
3454
** the open to fail if the database already exists.  The SQLITE_OPEN_EXCLUSIVE
3455
** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not
3456
** by sqlite3_open_v2().
3457
**
3458
** ^The fourth parameter to sqlite3_open_v2() is the name of the
3459
** [sqlite3_vfs] object that defines the operating system interface that
3460
** the new database connection should use.  ^If the fourth parameter is
3461
** a NULL pointer then the default [sqlite3_vfs] object is used.
3462
**
3463
** ^If the filename is ":memory:", then a private, temporary in-memory database
3464
** is created for the connection.  ^This in-memory database will vanish when
3465
** the database connection is closed.  Future versions of SQLite might
3466
** make use of additional special filenames that begin with the ":" character.
3467
** It is recommended that when a database filename actually does begin with
3468
** a ":" character you should prefix the filename with a pathname such as
3469
** "./" to avoid ambiguity.
3470
**
3471
** ^If the filename is an empty string, then a private, temporary
3472
** on-disk database will be created.  ^This private database will be
3473
** automatically deleted as soon as the database connection is closed.
3474
**
3475
** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
3476
**
3477
** ^If [URI filename] interpretation is enabled, and the filename argument
3478
** begins with "file:", then the filename is interpreted as a URI. ^URI
3479
** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
3480
** set in the third argument to sqlite3_open_v2(), or if it has
3481
** been enabled globally using the [SQLITE_CONFIG_URI] option with the
3482
** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
3483
** URI filename interpretation is turned off
3484
** by default, but future releases of SQLite might enable URI filename
3485
** interpretation by default.  See "[URI filenames]" for additional
3486
** information.
3487
**
3488
** URI filenames are parsed according to RFC 3986. ^If the URI contains an
3489
** authority, then it must be either an empty string or the string
3490
** "localhost". ^If the authority is not an empty string or "localhost", an
3491
** error is returned to the caller. ^The fragment component of a URI, if
3492
** present, is ignored.
3493
**
3494
** ^SQLite uses the path component of the URI as the name of the disk file
3495
** which contains the database. ^If the path begins with a '/' character,
3496
** then it is interpreted as an absolute path. ^If the path does not begin
3497
** with a '/' (meaning that the authority section is omitted from the URI)
3498
** then the path is interpreted as a relative path.
3499
** ^(On windows, the first component of an absolute path
3500
** is a drive specification (e.g. "C:").)^
3501
**
3502
** [[core URI query parameters]]
3503
** The query component of a URI may contain parameters that are interpreted
3504
** either by SQLite itself, or by a [VFS | custom VFS implementation].
3505
** SQLite and its built-in [VFSes] interpret the
3506
** following query parameters:
3507
**
3508
** <ul>
3509
**   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
3510
**     a VFS object that provides the operating system interface that should
3511
**     be used to access the database file on disk. ^If this option is set to
3512
**     an empty string the default VFS object is used. ^Specifying an unknown
3513
**     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
3514
**     present, then the VFS specified by the option takes precedence over
3515
**     the value passed as the fourth parameter to sqlite3_open_v2().
3516
**
3517
**   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
3518
**     "rwc", or "memory". Attempting to set it to any other value is
3519
**     an error)^.
3520
**     ^If "ro" is specified, then the database is opened for read-only
3521
**     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
3522
**     third argument to sqlite3_open_v2(). ^If the mode option is set to
3523
**     "rw", then the database is opened for read-write (but not create)
3524
**     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
3525
**     been set. ^Value "rwc" is equivalent to setting both
3526
**     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
3527
**     set to "memory" then a pure [in-memory database] that never reads
3528
**     or writes from disk is used. ^It is an error to specify a value for
3529
**     the mode parameter that is less restrictive than that specified by
3530
**     the flags passed in the third parameter to sqlite3_open_v2().
3531
**
3532
**   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
3533
**     "private". ^Setting it to "shared" is equivalent to setting the
3534
**     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
3535
**     sqlite3_open_v2(). ^Setting the cache parameter to "private" is
3536
**     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
3537
**     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
3538
**     a URI filename, its value overrides any behavior requested by setting
3539
**     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
3540
**
3541
**  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
3542
**     [powersafe overwrite] property does or does not apply to the
3543
**     storage media on which the database file resides.
3544
**
3545
**  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
3546
**     which if set disables file locking in rollback journal modes.  This
3547
**     is useful for accessing a database on a filesystem that does not
3548
**     support locking.  Caution:  Database corruption might result if two
3549
**     or more processes write to the same database and any one of those
3550
**     processes uses nolock=1.
3551
**
3552
**  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
3553
**     parameter that indicates that the database file is stored on
3554
**     read-only media.  ^When immutable is set, SQLite assumes that the
3555
**     database file cannot be changed, even by a process with higher
3556
**     privilege, and so the database is opened read-only and all locking
3557
**     and change detection is disabled.  Caution: Setting the immutable
3558
**     property on a database file that does in fact change can result
3559
**     in incorrect query results and/or [SQLITE_CORRUPT] errors.
3560
**     See also: [SQLITE_IOCAP_IMMUTABLE].
3561
**
3562
** </ul>
3563
**
3564
** ^Specifying an unknown parameter in the query component of a URI is not an
3565
** error.  Future versions of SQLite might understand additional query
3566
** parameters.  See "[query parameters with special meaning to SQLite]" for
3567
** additional information.
3568
**
3569
** [[URI filename examples]] <h3>URI filename examples</h3>
3570
**
3571
** <table border="1" align=center cellpadding=5>
3572
** <tr><th> URI filenames <th> Results
3573
** <tr><td> file:data.db <td>
3574
**          Open the file "data.db" in the current directory.
3575
** <tr><td> file:/home/fred/data.db<br>
3576
**          file:///home/fred/data.db <br>
3577
**          file://localhost/home/fred/data.db <br> <td>
3578
**          Open the database file "/home/fred/data.db".
3579
** <tr><td> file://darkstar/home/fred/data.db <td>
3580
**          An error. "darkstar" is not a recognized authority.
3581
** <tr><td style="white-space:nowrap">
3582
**          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
3583
**     <td> Windows only: Open the file "data.db" on fred's desktop on drive
3584
**          C:. Note that the %20 escaping in this example is not strictly
3585
**          necessary - space characters can be used literally
3586
**          in URI filenames.
3587
** <tr><td> file:data.db?mode=ro&cache=private <td>
3588
**          Open file "data.db" in the current directory for read-only access.
3589
**          Regardless of whether or not shared-cache mode is enabled by
3590
**          default, use a private cache.
3591
** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
3592
**          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
3593
**          that uses dot-files in place of posix advisory locking.
3594
** <tr><td> file:data.db?mode=readonly <td>
3595
**          An error. "readonly" is not a valid option for the "mode" parameter.
3596
**          Use "ro" instead:  "file:data.db?mode=ro".
3597
** </table>
3598
**
3599
** ^URI hexadecimal escape sequences (%HH) are supported within the path and
3600
** query components of a URI. A hexadecimal escape sequence consists of a
3601
** percent sign - "%" - followed by exactly two hexadecimal digits
3602
** specifying an octet value. ^Before the path or query components of a
3603
** URI filename are interpreted, they are encoded using UTF-8 and all
3604
** hexadecimal escape sequences replaced by a single byte containing the
3605
** corresponding octet. If this process generates an invalid UTF-8 encoding,
3606
** the results are undefined.
3607
**
3608
** <b>Note to Windows users:</b>  The encoding used for the filename argument
3609
** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
3610
** codepage is currently defined.  Filenames containing international
3611
** characters must be converted to UTF-8 prior to passing them into
3612
** sqlite3_open() or sqlite3_open_v2().
3613
**
3614
** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
3615
** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
3616
** features that require the use of temporary files may fail.
3617
**
3618
** See also: [sqlite3_temp_directory]
3619
*/
3620
SQLITE_API int sqlite3_open(
3621
  const char *filename,   /* Database filename (UTF-8) */
3622
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3623
);
3624
SQLITE_API int sqlite3_open16(
3625
  const void *filename,   /* Database filename (UTF-16) */
3626
  sqlite3 **ppDb          /* OUT: SQLite db handle */
3627
);
3628
SQLITE_API int sqlite3_open_v2(
3629
  const char *filename,   /* Database filename (UTF-8) */
3630
  sqlite3 **ppDb,         /* OUT: SQLite db handle */
3631
  int flags,              /* Flags */
3632
  const char *zVfs        /* Name of VFS module to use */
3633
);
3634
3635
/*
3636
** CAPI3REF: Obtain Values For URI Parameters
3637
**
3638
** These are utility routines, useful to [VFS|custom VFS implementations],
3639
** that check if a database file was a URI that contained a specific query
3640
** parameter, and if so obtains the value of that query parameter.
3641
**
3642
** The first parameter to these interfaces (hereafter referred to
3643
** as F) must be one of:
3644
** <ul>
3645
** <li> A database filename pointer created by the SQLite core and
3646
** passed into the xOpen() method of a VFS implemention, or
3647
** <li> A filename obtained from [sqlite3_db_filename()], or
3648
** <li> A new filename constructed using [sqlite3_create_filename()].
3649
** </ul>
3650
** If the F parameter is not one of the above, then the behavior is
3651
** undefined and probably undesirable.  Older versions of SQLite were
3652
** more tolerant of invalid F parameters than newer versions.
3653
**
3654
** If F is a suitable filename (as described in the previous paragraph)
3655
** and if P is the name of the query parameter, then
3656
** sqlite3_uri_parameter(F,P) returns the value of the P
3657
** parameter if it exists or a NULL pointer if P does not appear as a
3658
** query parameter on F.  If P is a query parameter of F and it
3659
** has no explicit value, then sqlite3_uri_parameter(F,P) returns
3660
** a pointer to an empty string.
3661
**
3662
** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
3663
** parameter and returns true (1) or false (0) according to the value
3664
** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
3665
** value of query parameter P is one of "yes", "true", or "on" in any
3666
** case or if the value begins with a non-zero number.  The
3667
** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
3668
** query parameter P is one of "no", "false", or "off" in any case or
3669
** if the value begins with a numeric zero.  If P is not a query
3670
** parameter on F or if the value of P does not match any of the
3671
** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
3672
**
3673
** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
3674
** 64-bit signed integer and returns that integer, or D if P does not
3675
** exist.  If the value of P is something other than an integer, then
3676
** zero is returned.
3677
**
3678
** The sqlite3_uri_key(F,N) returns a pointer to the name (not
3679
** the value) of the N-th query parameter for filename F, or a NULL
3680
** pointer if N is less than zero or greater than the number of query
3681
** parameters minus 1.  The N value is zero-based so N should be 0 to obtain
3682
** the name of the first query parameter, 1 for the second parameter, and
3683
** so forth.
3684
**
3685
** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
3686
** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
3687
** is not a database file pathname pointer that the SQLite core passed
3688
** into the xOpen VFS method, then the behavior of this routine is undefined
3689
** and probably undesirable.
3690
**
3691
** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F
3692
** parameter can also be the name of a rollback journal file or WAL file
3693
** in addition to the main database file.  Prior to version 3.31.0, these
3694
** routines would only work if F was the name of the main database file.
3695
** When the F parameter is the name of the rollback journal or WAL file,
3696
** it has access to all the same query parameters as were found on the
3697
** main database file.
3698
**
3699
** See the [URI filename] documentation for additional information.
3700
*/
3701
SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
3702
SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
3703
SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
3704
SQLITE_API const char *sqlite3_uri_key(const char *zFilename, int N);
3705
3706
/*
3707
** CAPI3REF:  Translate filenames
3708
**
3709
** These routines are available to [VFS|custom VFS implementations] for
3710
** translating filenames between the main database file, the journal file,
3711
** and the WAL file.
3712
**
3713
** If F is the name of an sqlite database file, journal file, or WAL file
3714
** passed by the SQLite core into the VFS, then sqlite3_filename_database(F)
3715
** returns the name of the corresponding database file.
3716
**
3717
** If F is the name of an sqlite database file, journal file, or WAL file
3718
** passed by the SQLite core into the VFS, or if F is a database filename
3719
** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F)
3720
** returns the name of the corresponding rollback journal file.
3721
**
3722
** If F is the name of an sqlite database file, journal file, or WAL file
3723
** that was passed by the SQLite core into the VFS, or if F is a database
3724
** filename obtained from [sqlite3_db_filename()], then
3725
** sqlite3_filename_wal(F) returns the name of the corresponding
3726
** WAL file.
3727
**
3728
** In all of the above, if F is not the name of a database, journal or WAL
3729
** filename passed into the VFS from the SQLite core and F is not the
3730
** return value from [sqlite3_db_filename()], then the result is
3731
** undefined and is likely a memory access violation.
3732
*/
3733
SQLITE_API const char *sqlite3_filename_database(const char*);
3734
SQLITE_API const char *sqlite3_filename_journal(const char*);
3735
SQLITE_API const char *sqlite3_filename_wal(const char*);
3736
3737
/*
3738
** CAPI3REF:  Database File Corresponding To A Journal
3739
**
3740
** ^If X is the name of a rollback or WAL-mode journal file that is
3741
** passed into the xOpen method of [sqlite3_vfs], then
3742
** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]
3743
** object that represents the main database file.
3744
**
3745
** This routine is intended for use in custom [VFS] implementations
3746
** only.  It is not a general-purpose interface.
3747
** The argument sqlite3_file_object(X) must be a filename pointer that
3748
** has been passed into [sqlite3_vfs].xOpen method where the
3749
** flags parameter to xOpen contains one of the bits
3750
** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL].  Any other use
3751
** of this routine results in undefined and probably undesirable
3752
** behavior.
3753
*/
3754
SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*);
3755
3756
/*
3757
** CAPI3REF: Create and Destroy VFS Filenames
3758
**
3759
** These interfces are provided for use by [VFS shim] implementations and
3760
** are not useful outside of that context.
3761
**
3762
** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of
3763
** database filename D with corresponding journal file J and WAL file W and
3764
** with N URI parameters key/values pairs in the array P.  The result from
3765
** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that
3766
** is safe to pass to routines like:
3767
** <ul>
3768
** <li> [sqlite3_uri_parameter()],
3769
** <li> [sqlite3_uri_boolean()],
3770
** <li> [sqlite3_uri_int64()],
3771
** <li> [sqlite3_uri_key()],
3772
** <li> [sqlite3_filename_database()],
3773
** <li> [sqlite3_filename_journal()], or
3774
** <li> [sqlite3_filename_wal()].
3775
** </ul>
3776
** If a memory allocation error occurs, sqlite3_create_filename() might
3777
** return a NULL pointer.  The memory obtained from sqlite3_create_filename(X)
3778
** must be released by a corresponding call to sqlite3_free_filename(Y).
3779
**
3780
** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array
3781
** of 2*N pointers to strings.  Each pair of pointers in this array corresponds
3782
** to a key and value for a query parameter.  The P parameter may be a NULL
3783
** pointer if N is zero.  None of the 2*N pointers in the P array may be
3784
** NULL pointers and key pointers should not be empty strings.
3785
** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may
3786
** be NULL pointers, though they can be empty strings.
3787
**
3788
** The sqlite3_free_filename(Y) routine releases a memory allocation
3789
** previously obtained from sqlite3_create_filename().  Invoking
3790
** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
3791
**
3792
** If the Y parameter to sqlite3_free_filename(Y) is anything other
3793
** than a NULL pointer or a pointer previously acquired from
3794
** sqlite3_create_filename(), then bad things such as heap
3795
** corruption or segfaults may occur. The value Y should not be
3796
** used again after sqlite3_free_filename(Y) has been called.  This means
3797
** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
3798
** then the corresponding [sqlite3_module.xClose() method should also be
3799
** invoked prior to calling sqlite3_free_filename(Y).
3800
*/
3801
SQLITE_API char *sqlite3_create_filename(
3802
  const char *zDatabase,
3803
  const char *zJournal,
3804
  const char *zWal,
3805
  int nParam,
3806
  const char **azParam
3807
);
3808
SQLITE_API void sqlite3_free_filename(char*);
3809
3810
/*
3811
** CAPI3REF: Error Codes And Messages
3812
** METHOD: sqlite3
3813
**
3814
** ^If the most recent sqlite3_* API call associated with
3815
** [database connection] D failed, then the sqlite3_errcode(D) interface
3816
** returns the numeric [result code] or [extended result code] for that
3817
** API call.
3818
** ^The sqlite3_extended_errcode()
3819
** interface is the same except that it always returns the
3820
** [extended result code] even when extended result codes are
3821
** disabled.
3822
**
3823
** The values returned by sqlite3_errcode() and/or
3824
** sqlite3_extended_errcode() might change with each API call.
3825
** Except, there are some interfaces that are guaranteed to never
3826
** change the value of the error code.  The error-code preserving
3827
** interfaces include the following:
3828
**
3829
** <ul>
3830
** <li> sqlite3_errcode()
3831
** <li> sqlite3_extended_errcode()
3832
** <li> sqlite3_errmsg()
3833
** <li> sqlite3_errmsg16()
3834
** <li> sqlite3_error_offset()
3835
** </ul>
3836
**
3837
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
3838
** text that describes the error, as either UTF-8 or UTF-16 respectively.
3839
** ^(Memory to hold the error message string is managed internally.
3840
** The application does not need to worry about freeing the result.
3841
** However, the error string might be overwritten or deallocated by
3842
** subsequent calls to other SQLite interface functions.)^
3843
**
3844
** ^The sqlite3_errstr() interface returns the English-language text
3845
** that describes the [result code], as UTF-8.
3846
** ^(Memory to hold the error message string is managed internally
3847
** and must not be freed by the application)^.
3848
**
3849
** ^If the most recent error references a specific token in the input
3850
** SQL, the sqlite3_error_offset() interface returns the byte offset
3851
** of the start of that token.  ^The byte offset returned by
3852
** sqlite3_error_offset() assumes that the input SQL is UTF8.
3853
** ^If the most recent error does not reference a specific token in the input
3854
** SQL, then the sqlite3_error_offset() function returns -1.
3855
**
3856
** When the serialized [threading mode] is in use, it might be the
3857
** case that a second error occurs on a separate thread in between
3858
** the time of the first error and the call to these interfaces.
3859
** When that happens, the second error will be reported since these
3860
** interfaces always report the most recent result.  To avoid
3861
** this, each thread can obtain exclusive use of the [database connection] D
3862
** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
3863
** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
3864
** all calls to the interfaces listed here are completed.
3865
**
3866
** If an interface fails with SQLITE_MISUSE, that means the interface
3867
** was invoked incorrectly by the application.  In that case, the
3868
** error code and message may or may not be set.
3869
*/
3870
SQLITE_API int sqlite3_errcode(sqlite3 *db);
3871
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
3872
SQLITE_API const char *sqlite3_errmsg(sqlite3*);
3873
SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
3874
SQLITE_API const char *sqlite3_errstr(int);
3875
SQLITE_API int sqlite3_error_offset(sqlite3 *db);
3876
3877
/*
3878
** CAPI3REF: Prepared Statement Object
3879
** KEYWORDS: {prepared statement} {prepared statements}
3880
**
3881
** An instance of this object represents a single SQL statement that
3882
** has been compiled into binary form and is ready to be evaluated.
3883
**
3884
** Think of each SQL statement as a separate computer program.  The
3885
** original SQL text is source code.  A prepared statement object
3886
** is the compiled object code.  All SQL must be converted into a
3887
** prepared statement before it can be run.
3888
**
3889
** The life-cycle of a prepared statement object usually goes like this:
3890
**
3891
** <ol>
3892
** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
3893
** <li> Bind values to [parameters] using the sqlite3_bind_*()
3894
**      interfaces.
3895
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
3896
** <li> Reset the prepared statement using [sqlite3_reset()] then go back
3897
**      to step 2.  Do this zero or more times.
3898
** <li> Destroy the object using [sqlite3_finalize()].
3899
** </ol>
3900
*/
3901
typedef struct sqlite3_stmt sqlite3_stmt;
3902
3903
/*
3904
** CAPI3REF: Run-time Limits
3905
** METHOD: sqlite3
3906
**
3907
** ^(This interface allows the size of various constructs to be limited
3908
** on a connection by connection basis.  The first parameter is the
3909
** [database connection] whose limit is to be set or queried.  The
3910
** second parameter is one of the [limit categories] that define a
3911
** class of constructs to be size limited.  The third parameter is the
3912
** new limit for that construct.)^
3913
**
3914
** ^If the new limit is a negative number, the limit is unchanged.
3915
** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
3916
** [limits | hard upper bound]
3917
** set at compile-time by a C preprocessor macro called
3918
** [limits | SQLITE_MAX_<i>NAME</i>].
3919
** (The "_LIMIT_" in the name is changed to "_MAX_".))^
3920
** ^Attempts to increase a limit above its hard upper bound are
3921
** silently truncated to the hard upper bound.
3922
**
3923
** ^Regardless of whether or not the limit was changed, the
3924
** [sqlite3_limit()] interface returns the prior value of the limit.
3925
** ^Hence, to find the current value of a limit without changing it,
3926
** simply invoke this interface with the third parameter set to -1.
3927
**
3928
** Run-time limits are intended for use in applications that manage
3929
** both their own internal database and also databases that are controlled
3930
** by untrusted external sources.  An example application might be a
3931
** web browser that has its own databases for storing history and
3932
** separate databases controlled by JavaScript applications downloaded
3933
** off the Internet.  The internal databases can be given the
3934
** large, default limits.  Databases managed by external sources can
3935
** be given much smaller limits designed to prevent a denial of service
3936
** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
3937
** interface to further control untrusted SQL.  The size of the database
3938
** created by an untrusted script can be contained using the
3939
** [max_page_count] [PRAGMA].
3940
**
3941
** New run-time limit categories may be added in future releases.
3942
*/
3943
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
3944
3945
/*
3946
** CAPI3REF: Run-Time Limit Categories
3947
** KEYWORDS: {limit category} {*limit categories}
3948
**
3949
** These constants define various performance limits
3950
** that can be lowered at run-time using [sqlite3_limit()].
3951
** The synopsis of the meanings of the various limits is shown below.
3952
** Additional information is available at [limits | Limits in SQLite].
3953
**
3954
** <dl>
3955
** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
3956
** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
3957
**
3958
** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
3959
** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
3960
**
3961
** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
3962
** <dd>The maximum number of columns in a table definition or in the
3963
** result set of a [SELECT] or the maximum number of columns in an index
3964
** or in an ORDER BY or GROUP BY clause.</dd>)^
3965
**
3966
** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
3967
** <dd>The maximum depth of the parse tree on any expression.</dd>)^
3968
**
3969
** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
3970
** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
3971
**
3972
** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
3973
** <dd>The maximum number of instructions in a virtual machine program
3974
** used to implement an SQL statement.  If [sqlite3_prepare_v2()] or
3975
** the equivalent tries to allocate space for more than this many opcodes
3976
** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
3977
**
3978
** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
3979
** <dd>The maximum number of arguments on a function.</dd>)^
3980
**
3981
** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
3982
** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
3983
**
3984
** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
3985
** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
3986
** <dd>The maximum length of the pattern argument to the [LIKE] or
3987
** [GLOB] operators.</dd>)^
3988
**
3989
** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
3990
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
3991
** <dd>The maximum index number of any [parameter] in an SQL statement.)^
3992
**
3993
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
3994
** <dd>The maximum depth of recursion for triggers.</dd>)^
3995
**
3996
** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
3997
** <dd>The maximum number of auxiliary worker threads that a single
3998
** [prepared statement] may start.</dd>)^
3999
** </dl>
4000
*/
4001
#define SQLITE_LIMIT_LENGTH                    0
4002
#define SQLITE_LIMIT_SQL_LENGTH                1
4003
#define SQLITE_LIMIT_COLUMN                    2
4004
#define SQLITE_LIMIT_EXPR_DEPTH                3
4005
#define SQLITE_LIMIT_COMPOUND_SELECT           4
4006
#define SQLITE_LIMIT_VDBE_OP                   5
4007
#define SQLITE_LIMIT_FUNCTION_ARG              6
4008
#define SQLITE_LIMIT_ATTACHED                  7
4009
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
4010
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
4011
#define SQLITE_LIMIT_TRIGGER_DEPTH            10
4012
#define SQLITE_LIMIT_WORKER_THREADS           11
4013
4014
/*
4015
** CAPI3REF: Prepare Flags
4016
**
4017
** These constants define various flags that can be passed into
4018
** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
4019
** [sqlite3_prepare16_v3()] interfaces.
4020
**
4021
** New flags may be added in future releases of SQLite.
4022
**
4023
** <dl>
4024
** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
4025
** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
4026
** that the prepared statement will be retained for a long time and
4027
** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
4028
** and [sqlite3_prepare16_v3()] assume that the prepared statement will
4029
** be used just once or at most a few times and then destroyed using
4030
** [sqlite3_finalize()] relatively soon. The current implementation acts
4031
** on this hint by avoiding the use of [lookaside memory] so as not to
4032
** deplete the limited store of lookaside memory. Future versions of
4033
** SQLite may act on this hint differently.
4034
**
4035
** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt>
4036
** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used
4037
** to be required for any prepared statement that wanted to use the
4038
** [sqlite3_normalized_sql()] interface.  However, the
4039
** [sqlite3_normalized_sql()] interface is now available to all
4040
** prepared statements, regardless of whether or not they use this
4041
** flag.
4042
**
4043
** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt>
4044
** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler
4045
** to return an error (error code SQLITE_ERROR) if the statement uses
4046
** any virtual tables.
4047
** </dl>
4048
*/
4049
#define SQLITE_PREPARE_PERSISTENT              0x01
4050
#define SQLITE_PREPARE_NORMALIZE               0x02
4051
#define SQLITE_PREPARE_NO_VTAB                 0x04
4052
4053
/*
4054
** CAPI3REF: Compiling An SQL Statement
4055
** KEYWORDS: {SQL statement compiler}
4056
** METHOD: sqlite3
4057
** CONSTRUCTOR: sqlite3_stmt
4058
**
4059
** To execute an SQL statement, it must first be compiled into a byte-code
4060
** program using one of these routines.  Or, in other words, these routines
4061
** are constructors for the [prepared statement] object.
4062
**
4063
** The preferred routine to use is [sqlite3_prepare_v2()].  The
4064
** [sqlite3_prepare()] interface is legacy and should be avoided.
4065
** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
4066
** for special purposes.
4067
**
4068
** The use of the UTF-8 interfaces is preferred, as SQLite currently
4069
** does all parsing using UTF-8.  The UTF-16 interfaces are provided
4070
** as a convenience.  The UTF-16 interfaces work by converting the
4071
** input text into UTF-8, then invoking the corresponding UTF-8 interface.
4072
**
4073
** The first argument, "db", is a [database connection] obtained from a
4074
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
4075
** [sqlite3_open16()].  The database connection must not have been closed.
4076
**
4077
** The second argument, "zSql", is the statement to be compiled, encoded
4078
** as either UTF-8 or UTF-16.  The sqlite3_prepare(), sqlite3_prepare_v2(),
4079
** and sqlite3_prepare_v3()
4080
** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
4081
** and sqlite3_prepare16_v3() use UTF-16.
4082
**
4083
** ^If the nByte argument is negative, then zSql is read up to the
4084
** first zero terminator. ^If nByte is positive, then it is the
4085
** number of bytes read from zSql.  ^If nByte is zero, then no prepared
4086
** statement is generated.
4087
** If the caller knows that the supplied string is nul-terminated, then
4088
** there is a small performance advantage to passing an nByte parameter that
4089
** is the number of bytes in the input string <i>including</i>
4090
** the nul-terminator.
4091
**
4092
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
4093
** past the end of the first SQL statement in zSql.  These routines only
4094
** compile the first statement in zSql, so *pzTail is left pointing to
4095
** what remains uncompiled.
4096
**
4097
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
4098
** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
4099
** to NULL.  ^If the input text contains no SQL (if the input is an empty
4100
** string or a comment) then *ppStmt is set to NULL.
4101
** The calling procedure is responsible for deleting the compiled
4102
** SQL statement using [sqlite3_finalize()] after it has finished with it.
4103
** ppStmt may not be NULL.
4104
**
4105
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
4106
** otherwise an [error code] is returned.
4107
**
4108
** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
4109
** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
4110
** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
4111
** are retained for backwards compatibility, but their use is discouraged.
4112
** ^In the "vX" interfaces, the prepared statement
4113
** that is returned (the [sqlite3_stmt] object) contains a copy of the
4114
** original SQL text. This causes the [sqlite3_step()] interface to
4115
** behave differently in three ways:
4116
**
4117
** <ol>
4118
** <li>
4119
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
4120
** always used to do, [sqlite3_step()] will automatically recompile the SQL
4121
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
4122
** retries will occur before sqlite3_step() gives up and returns an error.
4123
** </li>
4124
**
4125
** <li>
4126
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
4127
** [error codes] or [extended error codes].  ^The legacy behavior was that
4128
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
4129
** and the application would have to make a second call to [sqlite3_reset()]
4130
** in order to find the underlying cause of the problem. With the "v2" prepare
4131
** interfaces, the underlying reason for the error is returned immediately.
4132
** </li>
4133
**
4134
** <li>
4135
** ^If the specific value bound to a [parameter | host parameter] in the
4136
** WHERE clause might influence the choice of query plan for a statement,
4137
** then the statement will be automatically recompiled, as if there had been
4138
** a schema change, on the first [sqlite3_step()] call following any change
4139
** to the [sqlite3_bind_text | bindings] of that [parameter].
4140
** ^The specific value of a WHERE-clause [parameter] might influence the
4141
** choice of query plan if the parameter is the left-hand side of a [LIKE]
4142
** or [GLOB] operator or if the parameter is compared to an indexed column
4143
** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled.
4144
** </li>
4145
** </ol>
4146
**
4147
** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
4148
** the extra prepFlags parameter, which is a bit array consisting of zero or
4149
** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags.  ^The
4150
** sqlite3_prepare_v2() interface works exactly the same as
4151
** sqlite3_prepare_v3() with a zero prepFlags parameter.
4152
*/
4153
SQLITE_API int sqlite3_prepare(
4154
  sqlite3 *db,            /* Database handle */
4155
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4156
  int nByte,              /* Maximum length of zSql in bytes. */
4157
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4158
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4159
);
4160
SQLITE_API int sqlite3_prepare_v2(
4161
  sqlite3 *db,            /* Database handle */
4162
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4163
  int nByte,              /* Maximum length of zSql in bytes. */
4164
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4165
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4166
);
4167
SQLITE_API int sqlite3_prepare_v3(
4168
  sqlite3 *db,            /* Database handle */
4169
  const char *zSql,       /* SQL statement, UTF-8 encoded */
4170
  int nByte,              /* Maximum length of zSql in bytes. */
4171
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4172
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4173
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
4174
);
4175
SQLITE_API int sqlite3_prepare16(
4176
  sqlite3 *db,            /* Database handle */
4177
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4178
  int nByte,              /* Maximum length of zSql in bytes. */
4179
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4180
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4181
);
4182
SQLITE_API int sqlite3_prepare16_v2(
4183
  sqlite3 *db,            /* Database handle */
4184
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4185
  int nByte,              /* Maximum length of zSql in bytes. */
4186
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4187
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4188
);
4189
SQLITE_API int sqlite3_prepare16_v3(
4190
  sqlite3 *db,            /* Database handle */
4191
  const void *zSql,       /* SQL statement, UTF-16 encoded */
4192
  int nByte,              /* Maximum length of zSql in bytes. */
4193
  unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
4194
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
4195
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
4196
);
4197
4198
/*
4199
** CAPI3REF: Retrieving Statement SQL
4200
** METHOD: sqlite3_stmt
4201
**
4202
** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
4203
** SQL text used to create [prepared statement] P if P was
4204
** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
4205
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4206
** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
4207
** string containing the SQL text of prepared statement P with
4208
** [bound parameters] expanded.
4209
** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8
4210
** string containing the normalized SQL text of prepared statement P.  The
4211
** semantics used to normalize a SQL statement are unspecified and subject
4212
** to change.  At a minimum, literal values will be replaced with suitable
4213
** placeholders.
4214
**
4215
** ^(For example, if a prepared statement is created using the SQL
4216
** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
4217
** and parameter :xyz is unbound, then sqlite3_sql() will return
4218
** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
4219
** will return "SELECT 2345,NULL".)^
4220
**
4221
** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
4222
** is available to hold the result, or if the result would exceed the
4223
** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
4224
**
4225
** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
4226
** bound parameter expansions.  ^The [SQLITE_OMIT_TRACE] compile-time
4227
** option causes sqlite3_expanded_sql() to always return NULL.
4228
**
4229
** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P)
4230
** are managed by SQLite and are automatically freed when the prepared
4231
** statement is finalized.
4232
** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
4233
** is obtained from [sqlite3_malloc()] and must be freed by the application
4234
** by passing it to [sqlite3_free()].
4235
**
4236
** ^The sqlite3_normalized_sql() interface is only available if
4237
** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined.
4238
*/
4239
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
4240
SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
4241
#ifdef SQLITE_ENABLE_NORMALIZE
4242
SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt);
4243
#endif
4244
4245
/*
4246
** CAPI3REF: Determine If An SQL Statement Writes The Database
4247
** METHOD: sqlite3_stmt
4248
**
4249
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
4250
** and only if the [prepared statement] X makes no direct changes to
4251
** the content of the database file.
4252
**
4253
** Note that [application-defined SQL functions] or
4254
** [virtual tables] might change the database indirectly as a side effect.
4255
** ^(For example, if an application defines a function "eval()" that
4256
** calls [sqlite3_exec()], then the following SQL statement would
4257
** change the database file through side-effects:
4258
**
4259
** <blockquote><pre>
4260
**    SELECT eval('DELETE FROM t1') FROM t2;
4261
** </pre></blockquote>
4262
**
4263
** But because the [SELECT] statement does not change the database file
4264
** directly, sqlite3_stmt_readonly() would still return true.)^
4265
**
4266
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
4267
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
4268
** since the statements themselves do not actually modify the database but
4269
** rather they control the timing of when other statements modify the
4270
** database.  ^The [ATTACH] and [DETACH] statements also cause
4271
** sqlite3_stmt_readonly() to return true since, while those statements
4272
** change the configuration of a database connection, they do not make
4273
** changes to the content of the database files on disk.
4274
** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
4275
** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
4276
** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
4277
** sqlite3_stmt_readonly() returns false for those commands.
4278
**
4279
** ^This routine returns false if there is any possibility that the
4280
** statement might change the database file.  ^A false return does
4281
** not guarantee that the statement will change the database file.
4282
** ^For example, an UPDATE statement might have a WHERE clause that
4283
** makes it a no-op, but the sqlite3_stmt_readonly() result would still
4284
** be false.  ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a
4285
** read-only no-op if the table already exists, but
4286
** sqlite3_stmt_readonly() still returns false for such a statement.
4287
**
4288
** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN]
4289
** statement, then sqlite3_stmt_readonly(X) returns the same value as
4290
** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted.
4291
*/
4292
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
4293
4294
/*
4295
** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
4296
** METHOD: sqlite3_stmt
4297
**
4298
** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
4299
** prepared statement S is an EXPLAIN statement, or 2 if the
4300
** statement S is an EXPLAIN QUERY PLAN.
4301
** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
4302
** an ordinary statement or a NULL pointer.
4303
*/
4304
SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);
4305
4306
/*
4307
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
4308
** METHOD: sqlite3_stmt
4309
**
4310
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
4311
** [prepared statement] S has been stepped at least once using
4312
** [sqlite3_step(S)] but has neither run to completion (returned
4313
** [SQLITE_DONE] from [sqlite3_step(S)]) nor
4314
** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
4315
** interface returns false if S is a NULL pointer.  If S is not a
4316
** NULL pointer and is not a pointer to a valid [prepared statement]
4317
** object, then the behavior is undefined and probably undesirable.
4318
**
4319
** This interface can be used in combination [sqlite3_next_stmt()]
4320
** to locate all prepared statements associated with a database
4321
** connection that are in need of being reset.  This can be used,
4322
** for example, in diagnostic routines to search for prepared
4323
** statements that are holding a transaction open.
4324
*/
4325
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
4326
4327
/*
4328
** CAPI3REF: Dynamically Typed Value Object
4329
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
4330
**
4331
** SQLite uses the sqlite3_value object to represent all values
4332
** that can be stored in a database table. SQLite uses dynamic typing
4333
** for the values it stores.  ^Values stored in sqlite3_value objects
4334
** can be integers, floating point values, strings, BLOBs, or NULL.
4335
**
4336
** An sqlite3_value object may be either "protected" or "unprotected".
4337
** Some interfaces require a protected sqlite3_value.  Other interfaces
4338
** will accept either a protected or an unprotected sqlite3_value.
4339
** Every interface that accepts sqlite3_value arguments specifies
4340
** whether or not it requires a protected sqlite3_value.  The
4341
** [sqlite3_value_dup()] interface can be used to construct a new
4342
** protected sqlite3_value from an unprotected sqlite3_value.
4343
**
4344
** The terms "protected" and "unprotected" refer to whether or not
4345
** a mutex is held.  An internal mutex is held for a protected
4346
** sqlite3_value object but no mutex is held for an unprotected
4347
** sqlite3_value object.  If SQLite is compiled to be single-threaded
4348
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
4349
** or if SQLite is run in one of reduced mutex modes
4350
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
4351
** then there is no distinction between protected and unprotected
4352
** sqlite3_value objects and they can be used interchangeably.  However,
4353
** for maximum code portability it is recommended that applications
4354
** still make the distinction between protected and unprotected
4355
** sqlite3_value objects even when not strictly required.
4356
**
4357
** ^The sqlite3_value objects that are passed as parameters into the
4358
** implementation of [application-defined SQL functions] are protected.
4359
** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()]
4360
** are protected.
4361
** ^The sqlite3_value object returned by
4362
** [sqlite3_column_value()] is unprotected.
4363
** Unprotected sqlite3_value objects may only be used as arguments
4364
** to [sqlite3_result_value()], [sqlite3_bind_value()], and
4365
** [sqlite3_value_dup()].
4366
** The [sqlite3_value_blob | sqlite3_value_type()] family of
4367
** interfaces require protected sqlite3_value objects.
4368
*/
4369
typedef struct sqlite3_value sqlite3_value;
4370
4371
/*
4372
** CAPI3REF: SQL Function Context Object
4373
**
4374
** The context in which an SQL function executes is stored in an
4375
** sqlite3_context object.  ^A pointer to an sqlite3_context object
4376
** is always first parameter to [application-defined SQL functions].
4377
** The application-defined SQL function implementation will pass this
4378
** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
4379
** [sqlite3_aggregate_context()], [sqlite3_user_data()],
4380
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
4381
** and/or [sqlite3_set_auxdata()].
4382
*/
4383
typedef struct sqlite3_context sqlite3_context;
4384
4385
/*
4386
** CAPI3REF: Binding Values To Prepared Statements
4387
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
4388
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
4389
** METHOD: sqlite3_stmt
4390
**
4391
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
4392
** literals may be replaced by a [parameter] that matches one of following
4393
** templates:
4394
**
4395
** <ul>
4396
** <li>  ?
4397
** <li>  ?NNN
4398
** <li>  :VVV
4399
** <li>  @VVV
4400
** <li>  $VVV
4401
** </ul>
4402
**
4403
** In the templates above, NNN represents an integer literal,
4404
** and VVV represents an alphanumeric identifier.)^  ^The values of these
4405
** parameters (also called "host parameter names" or "SQL parameters")
4406
** can be set using the sqlite3_bind_*() routines defined here.
4407
**
4408
** ^The first argument to the sqlite3_bind_*() routines is always
4409
** a pointer to the [sqlite3_stmt] object returned from
4410
** [sqlite3_prepare_v2()] or its variants.
4411
**
4412
** ^The second argument is the index of the SQL parameter to be set.
4413
** ^The leftmost SQL parameter has an index of 1.  ^When the same named
4414
** SQL parameter is used more than once, second and subsequent
4415
** occurrences have the same index as the first occurrence.
4416
** ^The index for named parameters can be looked up using the
4417
** [sqlite3_bind_parameter_index()] API if desired.  ^The index
4418
** for "?NNN" parameters is the value of NNN.
4419
** ^The NNN value must be between 1 and the [sqlite3_limit()]
4420
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766).
4421
**
4422
** ^The third argument is the value to bind to the parameter.
4423
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4424
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
4425
** is ignored and the end result is the same as sqlite3_bind_null().
4426
** ^If the third parameter to sqlite3_bind_text() is not NULL, then
4427
** it should be a pointer to well-formed UTF8 text.
4428
** ^If the third parameter to sqlite3_bind_text16() is not NULL, then
4429
** it should be a pointer to well-formed UTF16 text.
4430
** ^If the third parameter to sqlite3_bind_text64() is not NULL, then
4431
** it should be a pointer to a well-formed unicode string that is
4432
** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16
4433
** otherwise.
4434
**
4435
** [[byte-order determination rules]] ^The byte-order of
4436
** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF)
4437
** found in first character, which is removed, or in the absence of a BOM
4438
** the byte order is the native byte order of the host
4439
** machine for sqlite3_bind_text16() or the byte order specified in
4440
** the 6th parameter for sqlite3_bind_text64().)^
4441
** ^If UTF16 input text contains invalid unicode
4442
** characters, then SQLite might change those invalid characters
4443
** into the unicode replacement character: U+FFFD.
4444
**
4445
** ^(In those routines that have a fourth argument, its value is the
4446
** number of bytes in the parameter.  To be clear: the value is the
4447
** number of <u>bytes</u> in the value, not the number of characters.)^
4448
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
4449
** is negative, then the length of the string is
4450
** the number of bytes up to the first zero terminator.
4451
** If the fourth parameter to sqlite3_bind_blob() is negative, then
4452
** the behavior is undefined.
4453
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
4454
** or sqlite3_bind_text16() or sqlite3_bind_text64() then
4455
** that parameter must be the byte offset
4456
** where the NUL terminator would occur assuming the string were NUL
4457
** terminated.  If any NUL characters occurs at byte offsets less than
4458
** the value of the fourth parameter then the resulting string value will
4459
** contain embedded NULs.  The result of expressions involving strings
4460
** with embedded NULs is undefined.
4461
**
4462
** ^The fifth argument to the BLOB and string binding interfaces controls
4463
** or indicates the lifetime of the object referenced by the third parameter.
4464
** These three options exist:
4465
** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished
4466
** with it may be passed. ^It is called to dispose of the BLOB or string even
4467
** if the call to the bind API fails, except the destructor is not called if
4468
** the third parameter is a NULL pointer or the fourth parameter is negative.
4469
** ^ (2) The special constant, [SQLITE_STATIC], may be passsed to indicate that
4470
** the application remains responsible for disposing of the object. ^In this
4471
** case, the object and the provided pointer to it must remain valid until
4472
** either the prepared statement is finalized or the same SQL parameter is
4473
** bound to something else, whichever occurs sooner.
4474
** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the
4475
** object is to be copied prior to the return from sqlite3_bind_*(). ^The
4476
** object and pointer to it must remain valid until then. ^SQLite will then
4477
** manage the lifetime of its private copy.
4478
**
4479
** ^The sixth argument to sqlite3_bind_text64() must be one of
4480
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
4481
** to specify the encoding of the text in the third parameter.  If
4482
** the sixth argument to sqlite3_bind_text64() is not one of the
4483
** allowed values shown above, or if the text encoding is different
4484
** from the encoding specified by the sixth parameter, then the behavior
4485
** is undefined.
4486
**
4487
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
4488
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
4489
** (just an integer to hold its size) while it is being processed.
4490
** Zeroblobs are intended to serve as placeholders for BLOBs whose
4491
** content is later written using
4492
** [sqlite3_blob_open | incremental BLOB I/O] routines.
4493
** ^A negative value for the zeroblob results in a zero-length BLOB.
4494
**
4495
** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
4496
** [prepared statement] S to have an SQL value of NULL, but to also be
4497
** associated with the pointer P of type T.  ^D is either a NULL pointer or
4498
** a pointer to a destructor function for P. ^SQLite will invoke the
4499
** destructor D with a single argument of P when it is finished using
4500
** P.  The T parameter should be a static string, preferably a string
4501
** literal. The sqlite3_bind_pointer() routine is part of the
4502
** [pointer passing interface] added for SQLite 3.20.0.
4503
**
4504
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
4505
** for the [prepared statement] or with a prepared statement for which
4506
** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
4507
** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
4508
** routine is passed a [prepared statement] that has been finalized, the
4509
** result is undefined and probably harmful.
4510
**
4511
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
4512
** ^Unbound parameters are interpreted as NULL.
4513
**
4514
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
4515
** [error code] if anything goes wrong.
4516
** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
4517
** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
4518
** [SQLITE_MAX_LENGTH].
4519
** ^[SQLITE_RANGE] is returned if the parameter
4520
** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
4521
**
4522
** See also: [sqlite3_bind_parameter_count()],
4523
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
4524
*/
4525
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
4526
SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
4527
                        void(*)(void*));
4528
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
4529
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
4530
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
4531
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
4532
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
4533
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
4534
SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
4535
                         void(*)(void*), unsigned char encoding);
4536
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
4537
SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
4538
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
4539
SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
4540
4541
/*
4542
** CAPI3REF: Number Of SQL Parameters
4543
** METHOD: sqlite3_stmt
4544
**
4545
** ^This routine can be used to find the number of [SQL parameters]
4546
** in a [prepared statement].  SQL parameters are tokens of the
4547
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
4548
** placeholders for values that are [sqlite3_bind_blob | bound]
4549
** to the parameters at a later time.
4550
**
4551
** ^(This routine actually returns the index of the largest (rightmost)
4552
** parameter. For all forms except ?NNN, this will correspond to the
4553
** number of unique parameters.  If parameters of the ?NNN form are used,
4554
** there may be gaps in the list.)^
4555
**
4556
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4557
** [sqlite3_bind_parameter_name()], and
4558
** [sqlite3_bind_parameter_index()].
4559
*/
4560
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
4561
4562
/*
4563
** CAPI3REF: Name Of A Host Parameter
4564
** METHOD: sqlite3_stmt
4565
**
4566
** ^The sqlite3_bind_parameter_name(P,N) interface returns
4567
** the name of the N-th [SQL parameter] in the [prepared statement] P.
4568
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
4569
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
4570
** respectively.
4571
** In other words, the initial ":" or "$" or "@" or "?"
4572
** is included as part of the name.)^
4573
** ^Parameters of the form "?" without a following integer have no name
4574
** and are referred to as "nameless" or "anonymous parameters".
4575
**
4576
** ^The first host parameter has an index of 1, not 0.
4577
**
4578
** ^If the value N is out of range or if the N-th parameter is
4579
** nameless, then NULL is returned.  ^The returned string is
4580
** always in UTF-8 encoding even if the named parameter was
4581
** originally specified as UTF-16 in [sqlite3_prepare16()],
4582
** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
4583
**
4584
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4585
** [sqlite3_bind_parameter_count()], and
4586
** [sqlite3_bind_parameter_index()].
4587
*/
4588
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
4589
4590
/*
4591
** CAPI3REF: Index Of A Parameter With A Given Name
4592
** METHOD: sqlite3_stmt
4593
**
4594
** ^Return the index of an SQL parameter given its name.  ^The
4595
** index value returned is suitable for use as the second
4596
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
4597
** is returned if no matching parameter is found.  ^The parameter
4598
** name must be given in UTF-8 even if the original statement
4599
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
4600
** [sqlite3_prepare16_v3()].
4601
**
4602
** See also: [sqlite3_bind_blob|sqlite3_bind()],
4603
** [sqlite3_bind_parameter_count()], and
4604
** [sqlite3_bind_parameter_name()].
4605
*/
4606
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
4607
4608
/*
4609
** CAPI3REF: Reset All Bindings On A Prepared Statement
4610
** METHOD: sqlite3_stmt
4611
**
4612
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
4613
** the [sqlite3_bind_blob | bindings] on a [prepared statement].
4614
** ^Use this routine to reset all host parameters to NULL.
4615
*/
4616
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
4617
4618
/*
4619
** CAPI3REF: Number Of Columns In A Result Set
4620
** METHOD: sqlite3_stmt
4621
**
4622
** ^Return the number of columns in the result set returned by the
4623
** [prepared statement]. ^If this routine returns 0, that means the
4624
** [prepared statement] returns no data (for example an [UPDATE]).
4625
** ^However, just because this routine returns a positive number does not
4626
** mean that one or more rows of data will be returned.  ^A SELECT statement
4627
** will always have a positive sqlite3_column_count() but depending on the
4628
** WHERE clause constraints and the table content, it might return no rows.
4629
**
4630
** See also: [sqlite3_data_count()]
4631
*/
4632
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
4633
4634
/*
4635
** CAPI3REF: Column Names In A Result Set
4636
** METHOD: sqlite3_stmt
4637
**
4638
** ^These routines return the name assigned to a particular column
4639
** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
4640
** interface returns a pointer to a zero-terminated UTF-8 string
4641
** and sqlite3_column_name16() returns a pointer to a zero-terminated
4642
** UTF-16 string.  ^The first parameter is the [prepared statement]
4643
** that implements the [SELECT] statement. ^The second parameter is the
4644
** column number.  ^The leftmost column is number 0.
4645
**
4646
** ^The returned string pointer is valid until either the [prepared statement]
4647
** is destroyed by [sqlite3_finalize()] or until the statement is automatically
4648
** reprepared by the first call to [sqlite3_step()] for a particular run
4649
** or until the next call to
4650
** sqlite3_column_name() or sqlite3_column_name16() on the same column.
4651
**
4652
** ^If sqlite3_malloc() fails during the processing of either routine
4653
** (for example during a conversion from UTF-8 to UTF-16) then a
4654
** NULL pointer is returned.
4655
**
4656
** ^The name of a result column is the value of the "AS" clause for
4657
** that column, if there is an AS clause.  If there is no AS clause
4658
** then the name of the column is unspecified and may change from
4659
** one release of SQLite to the next.
4660
*/
4661
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
4662
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
4663
4664
/*
4665
** CAPI3REF: Source Of Data In A Query Result
4666
** METHOD: sqlite3_stmt
4667
**
4668
** ^These routines provide a means to determine the database, table, and
4669
** table column that is the origin of a particular result column in
4670
** [SELECT] statement.
4671
** ^The name of the database or table or column can be returned as
4672
** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
4673
** the database name, the _table_ routines return the table name, and
4674
** the origin_ routines return the column name.
4675
** ^The returned string is valid until the [prepared statement] is destroyed
4676
** using [sqlite3_finalize()] or until the statement is automatically
4677
** reprepared by the first call to [sqlite3_step()] for a particular run
4678
** or until the same information is requested
4679
** again in a different encoding.
4680
**
4681
** ^The names returned are the original un-aliased names of the
4682
** database, table, and column.
4683
**
4684
** ^The first argument to these interfaces is a [prepared statement].
4685
** ^These functions return information about the Nth result column returned by
4686
** the statement, where N is the second function argument.
4687
** ^The left-most column is column 0 for these routines.
4688
**
4689
** ^If the Nth column returned by the statement is an expression or
4690
** subquery and is not a column value, then all of these functions return
4691
** NULL.  ^These routines might also return NULL if a memory allocation error
4692
** occurs.  ^Otherwise, they return the name of the attached database, table,
4693
** or column that query result column was extracted from.
4694
**
4695
** ^As with all other SQLite APIs, those whose names end with "16" return
4696
** UTF-16 encoded strings and the other functions return UTF-8.
4697
**
4698
** ^These APIs are only available if the library was compiled with the
4699
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
4700
**
4701
** If two or more threads call one or more
4702
** [sqlite3_column_database_name | column metadata interfaces]
4703
** for the same [prepared statement] and result column
4704
** at the same time then the results are undefined.
4705
*/
4706
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
4707
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
4708
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
4709
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
4710
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
4711
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
4712
4713
/*
4714
** CAPI3REF: Declared Datatype Of A Query Result
4715
** METHOD: sqlite3_stmt
4716
**
4717
** ^(The first parameter is a [prepared statement].
4718
** If this statement is a [SELECT] statement and the Nth column of the
4719
** returned result set of that [SELECT] is a table column (not an
4720
** expression or subquery) then the declared type of the table
4721
** column is returned.)^  ^If the Nth column of the result set is an
4722
** expression or subquery, then a NULL pointer is returned.
4723
** ^The returned string is always UTF-8 encoded.
4724
**
4725
** ^(For example, given the database schema:
4726
**
4727
** CREATE TABLE t1(c1 VARIANT);
4728
**
4729
** and the following statement to be compiled:
4730
**
4731
** SELECT c1 + 1, c1 FROM t1;
4732
**
4733
** this routine would return the string "VARIANT" for the second result
4734
** column (i==1), and a NULL pointer for the first result column (i==0).)^
4735
**
4736
** ^SQLite uses dynamic run-time typing.  ^So just because a column
4737
** is declared to contain a particular type does not mean that the
4738
** data stored in that column is of the declared type.  SQLite is
4739
** strongly typed, but the typing is dynamic not static.  ^Type
4740
** is associated with individual values, not with the containers
4741
** used to hold those values.
4742
*/
4743
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
4744
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
4745
4746
/*
4747
** CAPI3REF: Evaluate An SQL Statement
4748
** METHOD: sqlite3_stmt
4749
**
4750
** After a [prepared statement] has been prepared using any of
4751
** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
4752
** or [sqlite3_prepare16_v3()] or one of the legacy
4753
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
4754
** must be called one or more times to evaluate the statement.
4755
**
4756
** The details of the behavior of the sqlite3_step() interface depend
4757
** on whether the statement was prepared using the newer "vX" interfaces
4758
** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
4759
** [sqlite3_prepare16_v2()] or the older legacy
4760
** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
4761
** new "vX" interface is recommended for new applications but the legacy
4762
** interface will continue to be supported.
4763
**
4764
** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
4765
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
4766
** ^With the "v2" interface, any of the other [result codes] or
4767
** [extended result codes] might be returned as well.
4768
**
4769
** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
4770
** database locks it needs to do its job.  ^If the statement is a [COMMIT]
4771
** or occurs outside of an explicit transaction, then you can retry the
4772
** statement.  If the statement is not a [COMMIT] and occurs within an
4773
** explicit transaction then you should rollback the transaction before
4774
** continuing.
4775
**
4776
** ^[SQLITE_DONE] means that the statement has finished executing
4777
** successfully.  sqlite3_step() should not be called again on this virtual
4778
** machine without first calling [sqlite3_reset()] to reset the virtual
4779
** machine back to its initial state.
4780
**
4781
** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
4782
** is returned each time a new row of data is ready for processing by the
4783
** caller. The values may be accessed using the [column access functions].
4784
** sqlite3_step() is called again to retrieve the next row of data.
4785
**
4786
** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
4787
** violation) has occurred.  sqlite3_step() should not be called again on
4788
** the VM. More information may be found by calling [sqlite3_errmsg()].
4789
** ^With the legacy interface, a more specific error code (for example,
4790
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
4791
** can be obtained by calling [sqlite3_reset()] on the
4792
** [prepared statement].  ^In the "v2" interface,
4793
** the more specific error code is returned directly by sqlite3_step().
4794
**
4795
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
4796
** Perhaps it was called on a [prepared statement] that has
4797
** already been [sqlite3_finalize | finalized] or on one that had
4798
** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
4799
** be the case that the same database connection is being used by two or
4800
** more threads at the same moment in time.
4801
**
4802
** For all versions of SQLite up to and including 3.6.23.1, a call to
4803
** [sqlite3_reset()] was required after sqlite3_step() returned anything
4804
** other than [SQLITE_ROW] before any subsequent invocation of
4805
** sqlite3_step().  Failure to reset the prepared statement using
4806
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
4807
** sqlite3_step().  But after [version 3.6.23.1] ([dateof:3.6.23.1],
4808
** sqlite3_step() began
4809
** calling [sqlite3_reset()] automatically in this circumstance rather
4810
** than returning [SQLITE_MISUSE].  This is not considered a compatibility
4811
** break because any application that ever receives an SQLITE_MISUSE error
4812
** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
4813
** can be used to restore the legacy behavior.
4814
**
4815
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
4816
** API always returns a generic error code, [SQLITE_ERROR], following any
4817
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
4818
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
4819
** specific [error codes] that better describes the error.
4820
** We admit that this is a goofy design.  The problem has been fixed
4821
** with the "v2" interface.  If you prepare all of your SQL statements
4822
** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
4823
** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
4824
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
4825
** then the more specific [error codes] are returned directly
4826
** by sqlite3_step().  The use of the "vX" interfaces is recommended.
4827
*/
4828
SQLITE_API int sqlite3_step(sqlite3_stmt*);
4829
4830
/*
4831
** CAPI3REF: Number of columns in a result set
4832
** METHOD: sqlite3_stmt
4833
**
4834
** ^The sqlite3_data_count(P) interface returns the number of columns in the
4835
** current row of the result set of [prepared statement] P.
4836
** ^If prepared statement P does not have results ready to return
4837
** (via calls to the [sqlite3_column_int | sqlite3_column()] family of
4838
** interfaces) then sqlite3_data_count(P) returns 0.
4839
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
4840
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
4841
** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
4842
** will return non-zero if previous call to [sqlite3_step](P) returned
4843
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
4844
** where it always returns zero since each step of that multi-step
4845
** pragma returns 0 columns of data.
4846
**
4847
** See also: [sqlite3_column_count()]
4848
*/
4849
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
4850
4851
/*
4852
** CAPI3REF: Fundamental Datatypes
4853
** KEYWORDS: SQLITE_TEXT
4854
**
4855
** ^(Every value in SQLite has one of five fundamental datatypes:
4856
**
4857
** <ul>
4858
** <li> 64-bit signed integer
4859
** <li> 64-bit IEEE floating point number
4860
** <li> string
4861
** <li> BLOB
4862
** <li> NULL
4863
** </ul>)^
4864
**
4865
** These constants are codes for each of those types.
4866
**
4867
** Note that the SQLITE_TEXT constant was also used in SQLite version 2
4868
** for a completely different meaning.  Software that links against both
4869
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
4870
** SQLITE_TEXT.
4871
*/
4872
#define SQLITE_INTEGER  1
4873
#define SQLITE_FLOAT    2
4874
#define SQLITE_BLOB     4
4875
#define SQLITE_NULL     5
4876
#ifdef SQLITE_TEXT
4877
# undef SQLITE_TEXT
4878
#else
4879
# define SQLITE_TEXT     3
4880
#endif
4881
#define SQLITE3_TEXT     3
4882
4883
/*
4884
** CAPI3REF: Result Values From A Query
4885
** KEYWORDS: {column access functions}
4886
** METHOD: sqlite3_stmt
4887
**
4888
** <b>Summary:</b>
4889
** <blockquote><table border=0 cellpadding=0 cellspacing=0>
4890
** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
4891
** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
4892
** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
4893
** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
4894
** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
4895
** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
4896
** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an
4897
** [sqlite3_value|unprotected sqlite3_value] object.
4898
** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
4899
** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
4900
** or a UTF-8 TEXT result in bytes
4901
** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
4902
** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
4903
** TEXT in bytes
4904
** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
4905
** datatype of the result
4906
** </table></blockquote>
4907
**
4908
** <b>Details:</b>
4909
**
4910
** ^These routines return information about a single column of the current
4911
** result row of a query.  ^In every case the first argument is a pointer
4912
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
4913
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
4914
** and the second argument is the index of the column for which information
4915
** should be returned. ^The leftmost column of the result set has the index 0.
4916
** ^The number of columns in the result can be determined using
4917
** [sqlite3_column_count()].
4918
**
4919
** If the SQL statement does not currently point to a valid row, or if the
4920
** column index is out of range, the result is undefined.
4921
** These routines may only be called when the most recent call to
4922
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
4923
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
4924
** If any of these routines are called after [sqlite3_reset()] or
4925
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
4926
** something other than [SQLITE_ROW], the results are undefined.
4927
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
4928
** are called from a different thread while any of these routines
4929
** are pending, then the results are undefined.
4930
**
4931
** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
4932
** each return the value of a result column in a specific data format.  If
4933
** the result column is not initially in the requested format (for example,
4934
** if the query returns an integer but the sqlite3_column_text() interface
4935
** is used to extract the value) then an automatic type conversion is performed.
4936
**
4937
** ^The sqlite3_column_type() routine returns the
4938
** [SQLITE_INTEGER | datatype code] for the initial data type
4939
** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
4940
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
4941
** The return value of sqlite3_column_type() can be used to decide which
4942
** of the first six interface should be used to extract the column value.
4943
** The value returned by sqlite3_column_type() is only meaningful if no
4944
** automatic type conversions have occurred for the value in question.
4945
** After a type conversion, the result of calling sqlite3_column_type()
4946
** is undefined, though harmless.  Future
4947
** versions of SQLite may change the behavior of sqlite3_column_type()
4948
** following a type conversion.
4949
**
4950
** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
4951
** or sqlite3_column_bytes16() interfaces can be used to determine the size
4952
** of that BLOB or string.
4953
**
4954
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
4955
** routine returns the number of bytes in that BLOB or string.
4956
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
4957
** the string to UTF-8 and then returns the number of bytes.
4958
** ^If the result is a numeric value then sqlite3_column_bytes() uses
4959
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
4960
** the number of bytes in that string.
4961
** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
4962
**
4963
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
4964
** routine returns the number of bytes in that BLOB or string.
4965
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
4966
** the string to UTF-16 and then returns the number of bytes.
4967
** ^If the result is a numeric value then sqlite3_column_bytes16() uses
4968
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
4969
** the number of bytes in that string.
4970
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
4971
**
4972
** ^The values returned by [sqlite3_column_bytes()] and
4973
** [sqlite3_column_bytes16()] do not include the zero terminators at the end
4974
** of the string.  ^For clarity: the values returned by
4975
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
4976
** bytes in the string, not the number of characters.
4977
**
4978
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
4979
** even empty strings, are always zero-terminated.  ^The return
4980
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
4981
**
4982
** ^Strings returned by sqlite3_column_text16() always have the endianness
4983
** which is native to the platform, regardless of the text encoding set
4984
** for the database.
4985
**
4986
** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
4987
** [unprotected sqlite3_value] object.  In a multithreaded environment,
4988
** an unprotected sqlite3_value object may only be used safely with
4989
** [sqlite3_bind_value()] and [sqlite3_result_value()].
4990
** If the [unprotected sqlite3_value] object returned by
4991
** [sqlite3_column_value()] is used in any other way, including calls
4992
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
4993
** or [sqlite3_value_bytes()], the behavior is not threadsafe.
4994
** Hence, the sqlite3_column_value() interface
4995
** is normally only useful within the implementation of
4996
** [application-defined SQL functions] or [virtual tables], not within
4997
** top-level application code.
4998
**
4999
** These routines may attempt to convert the datatype of the result.
5000
** ^For example, if the internal representation is FLOAT and a text result
5001
** is requested, [sqlite3_snprintf()] is used internally to perform the
5002
** conversion automatically.  ^(The following table details the conversions
5003
** that are applied:
5004
**
5005
** <blockquote>
5006
** <table border="1">
5007
** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
5008
**
5009
** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
5010
** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
5011
** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
5012
** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
5013
** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
5014
** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
5015
** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
5016
** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
5017
** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
5018
** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
5019
** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
5020
** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
5021
** <tr><td>  TEXT    <td>   BLOB    <td> No change
5022
** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
5023
** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
5024
** <tr><td>  BLOB    <td>   TEXT    <td> [CAST] to TEXT, ensure zero terminator
5025
** </table>
5026
** </blockquote>)^
5027
**
5028
** Note that when type conversions occur, pointers returned by prior
5029
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
5030
** sqlite3_column_text16() may be invalidated.
5031
** Type conversions and pointer invalidations might occur
5032
** in the following cases:
5033
**
5034
** <ul>
5035
** <li> The initial content is a BLOB and sqlite3_column_text() or
5036
**      sqlite3_column_text16() is called.  A zero-terminator might
5037
**      need to be added to the string.</li>
5038
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
5039
**      sqlite3_column_text16() is called.  The content must be converted
5040
**      to UTF-16.</li>
5041
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
5042
**      sqlite3_column_text() is called.  The content must be converted
5043
**      to UTF-8.</li>
5044
** </ul>
5045
**
5046
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
5047
** not invalidate a prior pointer, though of course the content of the buffer
5048
** that the prior pointer references will have been modified.  Other kinds
5049
** of conversion are done in place when it is possible, but sometimes they
5050
** are not possible and in those cases prior pointers are invalidated.
5051
**
5052
** The safest policy is to invoke these routines
5053
** in one of the following ways:
5054
**
5055
** <ul>
5056
**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
5057
**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
5058
**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
5059
** </ul>
5060
**
5061
** In other words, you should call sqlite3_column_text(),
5062
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
5063
** into the desired format, then invoke sqlite3_column_bytes() or
5064
** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
5065
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
5066
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
5067
** with calls to sqlite3_column_bytes().
5068
**
5069
** ^The pointers returned are valid until a type conversion occurs as
5070
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
5071
** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
5072
** and BLOBs is freed automatically.  Do not pass the pointers returned
5073
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
5074
** [sqlite3_free()].
5075
**
5076
** As long as the input parameters are correct, these routines will only
5077
** fail if an out-of-memory error occurs during a format conversion.
5078
** Only the following subset of interfaces are subject to out-of-memory
5079
** errors:
5080
**
5081
** <ul>
5082
** <li> sqlite3_column_blob()
5083
** <li> sqlite3_column_text()
5084
** <li> sqlite3_column_text16()
5085
** <li> sqlite3_column_bytes()
5086
** <li> sqlite3_column_bytes16()
5087
** </ul>
5088
**
5089
** If an out-of-memory error occurs, then the return value from these
5090
** routines is the same as if the column had contained an SQL NULL value.
5091
** Valid SQL NULL returns can be distinguished from out-of-memory errors
5092
** by invoking the [sqlite3_errcode()] immediately after the suspect
5093
** return value is obtained and before any
5094
** other SQLite interface is called on the same [database connection].
5095
*/
5096
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
5097
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
5098
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
5099
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
5100
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
5101
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
5102
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
5103
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
5104
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
5105
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
5106
5107
/*
5108
** CAPI3REF: Destroy A Prepared Statement Object
5109
** DESTRUCTOR: sqlite3_stmt
5110
**
5111
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
5112
** ^If the most recent evaluation of the statement encountered no errors
5113
** or if the statement is never been evaluated, then sqlite3_finalize() returns
5114
** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
5115
** sqlite3_finalize(S) returns the appropriate [error code] or
5116
** [extended error code].
5117
**
5118
** ^The sqlite3_finalize(S) routine can be called at any point during
5119
** the life cycle of [prepared statement] S:
5120
** before statement S is ever evaluated, after
5121
** one or more calls to [sqlite3_reset()], or after any call
5122
** to [sqlite3_step()] regardless of whether or not the statement has
5123
** completed execution.
5124
**
5125
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
5126
**
5127
** The application must finalize every [prepared statement] in order to avoid
5128
** resource leaks.  It is a grievous error for the application to try to use
5129
** a prepared statement after it has been finalized.  Any use of a prepared
5130
** statement after it has been finalized can result in undefined and
5131
** undesirable behavior such as segfaults and heap corruption.
5132
*/
5133
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
5134
5135
/*
5136
** CAPI3REF: Reset A Prepared Statement Object
5137
** METHOD: sqlite3_stmt
5138
**
5139
** The sqlite3_reset() function is called to reset a [prepared statement]
5140
** object back to its initial state, ready to be re-executed.
5141
** ^Any SQL statement variables that had values bound to them using
5142
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
5143
** Use [sqlite3_clear_bindings()] to reset the bindings.
5144
**
5145
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
5146
** back to the beginning of its program.
5147
**
5148
** ^If the most recent call to [sqlite3_step(S)] for the
5149
** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
5150
** or if [sqlite3_step(S)] has never before been called on S,
5151
** then [sqlite3_reset(S)] returns [SQLITE_OK].
5152
**
5153
** ^If the most recent call to [sqlite3_step(S)] for the
5154
** [prepared statement] S indicated an error, then
5155
** [sqlite3_reset(S)] returns an appropriate [error code].
5156
**
5157
** ^The [sqlite3_reset(S)] interface does not change the values
5158
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
5159
*/
5160
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
5161
5162
/*
5163
** CAPI3REF: Create Or Redefine SQL Functions
5164
** KEYWORDS: {function creation routines}
5165
** METHOD: sqlite3
5166
**
5167
** ^These functions (collectively known as "function creation routines")
5168
** are used to add SQL functions or aggregates or to redefine the behavior
5169
** of existing SQL functions or aggregates. The only differences between
5170
** the three "sqlite3_create_function*" routines are the text encoding
5171
** expected for the second parameter (the name of the function being
5172
** created) and the presence or absence of a destructor callback for
5173
** the application data pointer. Function sqlite3_create_window_function()
5174
** is similar, but allows the user to supply the extra callback functions
5175
** needed by [aggregate window functions].
5176
**
5177
** ^The first parameter is the [database connection] to which the SQL
5178
** function is to be added.  ^If an application uses more than one database
5179
** connection then application-defined SQL functions must be added
5180
** to each database connection separately.
5181
**
5182
** ^The second parameter is the name of the SQL function to be created or
5183
** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
5184
** representation, exclusive of the zero-terminator.  ^Note that the name
5185
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
5186
** ^Any attempt to create a function with a longer name
5187
** will result in [SQLITE_MISUSE] being returned.
5188
**
5189
** ^The third parameter (nArg)
5190
** is the number of arguments that the SQL function or
5191
** aggregate takes. ^If this parameter is -1, then the SQL function or
5192
** aggregate may take any number of arguments between 0 and the limit
5193
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
5194
** parameter is less than -1 or greater than 127 then the behavior is
5195
** undefined.
5196
**
5197
** ^The fourth parameter, eTextRep, specifies what
5198
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
5199
** its parameters.  The application should set this parameter to
5200
** [SQLITE_UTF16LE] if the function implementation invokes
5201
** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
5202
** implementation invokes [sqlite3_value_text16be()] on an input, or
5203
** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
5204