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drh75897232000-05-29 14:26:00 +00001/*
drhb19a2bc2001-09-16 00:13:26 +00002** 2001 September 15
drh75897232000-05-29 14:26:00 +00003**
drhb19a2bc2001-09-16 00:13:26 +00004** The author disclaims copyright to this source code. In place of
5** a legal notice, here is a blessing:
drh75897232000-05-29 14:26:00 +00006**
drhb19a2bc2001-09-16 00:13:26 +00007** May you do good and not evil.
8** May you find forgiveness for yourself and forgive others.
9** May you share freely, never taking more than you give.
drh75897232000-05-29 14:26:00 +000010**
11*************************************************************************
drhb19a2bc2001-09-16 00:13:26 +000012** This header file defines the interface that the SQLite library
drh6ed48bf2007-06-14 20:57:18 +000013** presents to client programs. If a C-function, structure, datatype,
14** or constant definition does not appear in this file, then it is
15** not a published API of SQLite, is subject to change without
16** notice, and should not be referenced by programs that use SQLite.
drh75897232000-05-29 14:26:00 +000017**
drh6ed48bf2007-06-14 20:57:18 +000018** Some of the definitions that are in this file are marked as
19** "experimental". Experimental interfaces are normally new
mihailima3f64902008-06-21 13:35:56 +000020** features recently added to SQLite. We do not anticipate changes
shane7c7c3112009-08-17 15:31:23 +000021** to experimental interfaces but reserve the right to make minor changes
22** if experience from use "in the wild" suggest such changes are prudent.
drh6ed48bf2007-06-14 20:57:18 +000023**
24** The official C-language API documentation for SQLite is derived
25** from comments in this file. This file is the authoritative source
26** on how SQLite interfaces are suppose to operate.
27**
28** The name of this file under configuration management is "sqlite.h.in".
29** The makefile makes some minor changes to this file (such as inserting
30** the version number) and changes its name to "sqlite3.h" as
31** part of the build process.
drh75897232000-05-29 14:26:00 +000032*/
drh12057d52004-09-06 17:34:12 +000033#ifndef _SQLITE3_H_
34#define _SQLITE3_H_
drha18c5682000-10-08 22:20:57 +000035#include <stdarg.h> /* Needed for the definition of va_list */
drh75897232000-05-29 14:26:00 +000036
37/*
drh382c0242001-10-06 16:33:02 +000038** Make sure we can call this stuff from C++.
39*/
40#ifdef __cplusplus
41extern "C" {
42#endif
43
drh6d2069d2007-08-14 01:58:53 +000044
drh382c0242001-10-06 16:33:02 +000045/*
drh73be5012007-08-08 12:11:21 +000046** Add the ability to override 'extern'
47*/
48#ifndef SQLITE_EXTERN
49# define SQLITE_EXTERN extern
50#endif
51
52/*
drh4d6618f2008-09-22 17:54:46 +000053** These no-op macros are used in front of interfaces to mark those
54** interfaces as either deprecated or experimental. New applications
shane7c7c3112009-08-17 15:31:23 +000055** should not use deprecated interfaces - they are support for backwards
drh4d6618f2008-09-22 17:54:46 +000056** compatibility only. Application writers should be aware that
57** experimental interfaces are subject to change in point releases.
58**
59** These macros used to resolve to various kinds of compiler magic that
60** would generate warning messages when they were used. But that
61** compiler magic ended up generating such a flurry of bug reports
62** that we have taken it all out and gone back to using simple
63** noop macros.
shanea79c3cc2008-08-11 17:27:01 +000064*/
drh4d6618f2008-09-22 17:54:46 +000065#define SQLITE_DEPRECATED
66#define SQLITE_EXPERIMENTAL
shanea79c3cc2008-08-11 17:27:01 +000067
68/*
mihailim362cc832008-06-21 06:16:42 +000069** Ensure these symbols were not defined by some previous header file.
drhb86ccfb2003-01-28 23:13:10 +000070*/
drh1e284f42004-10-06 15:52:01 +000071#ifdef SQLITE_VERSION
72# undef SQLITE_VERSION
drh1e284f42004-10-06 15:52:01 +000073#endif
drh6ed48bf2007-06-14 20:57:18 +000074#ifdef SQLITE_VERSION_NUMBER
75# undef SQLITE_VERSION_NUMBER
76#endif
danielk197799ba19e2005-02-05 07:33:34 +000077
78/*
drh1e15c032009-12-08 15:16:54 +000079** CAPI3REF: Compile-Time Library Version Numbers
drh6ed48bf2007-06-14 20:57:18 +000080**
drh1e15c032009-12-08 15:16:54 +000081** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
82** evaluates to a string literal that is the SQLite version in the
83** format "X.Y.Z" where X is the major version number (always 3 for
84** SQLite3) and Y is the minor version number and Z is the release number.)^
85** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
86** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
87** numbers used in [SQLITE_VERSION].)^
88** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
89** be larger than the release from which it is derived. Either Y will
90** be held constant and Z will be incremented or else Y will be incremented
91** and Z will be reset to zero.
drh6aa5f152009-08-19 15:57:07 +000092**
drh47baebc2009-08-14 16:01:24 +000093** Since version 3.6.18, SQLite source code has been stored in the
drh1e15c032009-12-08 15:16:54 +000094** <a href="http://www.fossil-scm.org/">Fossil configuration management
95** system</a>. ^The SQLITE_SOURCE_ID macro evalutes to
96** a string which identifies a particular check-in of SQLite
97** within its configuration management system. ^The SQLITE_SOURCE_ID
98** string contains the date and time of the check-in (UTC) and an SHA1
99** hash of the entire source tree.
drh47baebc2009-08-14 16:01:24 +0000100**
drh6aa5f152009-08-19 15:57:07 +0000101** See also: [sqlite3_libversion()],
drh4e0b31c2009-09-02 19:04:24 +0000102** [sqlite3_libversion_number()], [sqlite3_sourceid()],
103** [sqlite_version()] and [sqlite_source_id()].
danielk197799ba19e2005-02-05 07:33:34 +0000104*/
drh47baebc2009-08-14 16:01:24 +0000105#define SQLITE_VERSION "--VERS--"
106#define SQLITE_VERSION_NUMBER --VERSION-NUMBER--
107#define SQLITE_SOURCE_ID "--SOURCE-ID--"
drhb86ccfb2003-01-28 23:13:10 +0000108
109/*
drh1e15c032009-12-08 15:16:54 +0000110** CAPI3REF: Run-Time Library Version Numbers
shanehdc97a8c2010-02-23 20:08:35 +0000111** KEYWORDS: sqlite3_version, sqlite3_sourceid
drh6ed48bf2007-06-14 20:57:18 +0000112**
drh47baebc2009-08-14 16:01:24 +0000113** These interfaces provide the same information as the [SQLITE_VERSION],
drh1e15c032009-12-08 15:16:54 +0000114** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
drhd68eee02009-12-11 03:44:18 +0000115** but are associated with the library instead of the header file. ^(Cautious
drh4e0b31c2009-09-02 19:04:24 +0000116** programmers might include assert() statements in their application to
117** verify that values returned by these interfaces match the macros in
118** the header, and thus insure that the application is
drh6aa5f152009-08-19 15:57:07 +0000119** compiled with matching library and header files.
120**
121** <blockquote><pre>
122** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
drh4e0b31c2009-09-02 19:04:24 +0000123** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
drh1e15c032009-12-08 15:16:54 +0000124** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
drhd68eee02009-12-11 03:44:18 +0000125** </pre></blockquote>)^
drh6ed48bf2007-06-14 20:57:18 +0000126**
drh1e15c032009-12-08 15:16:54 +0000127** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
128** macro. ^The sqlite3_libversion() function returns a pointer to the
129** to the sqlite3_version[] string constant. The sqlite3_libversion()
130** function is provided for use in DLLs since DLL users usually do not have
131** direct access to string constants within the DLL. ^The
132** sqlite3_libversion_number() function returns an integer equal to
shanehbdea6d12010-02-23 04:19:54 +0000133** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
134** a pointer to a string constant whose value is the same as the
shanehdc97a8c2010-02-23 20:08:35 +0000135** [SQLITE_SOURCE_ID] C preprocessor macro.
drh33c1be32008-01-30 16:16:14 +0000136**
drh4e0b31c2009-09-02 19:04:24 +0000137** See also: [sqlite_version()] and [sqlite_source_id()].
drhb217a572000-08-22 13:40:18 +0000138*/
drh73be5012007-08-08 12:11:21 +0000139SQLITE_EXTERN const char sqlite3_version[];
drha3f70cb2004-09-30 14:24:50 +0000140const char *sqlite3_libversion(void);
drh47baebc2009-08-14 16:01:24 +0000141const char *sqlite3_sourceid(void);
danielk197799ba19e2005-02-05 07:33:34 +0000142int sqlite3_libversion_number(void);
143
144/*
shanehdc97a8c2010-02-23 20:08:35 +0000145** CAPI3REF: Run-Time Library Compilation Options Diagnostics
shanehdc97a8c2010-02-23 20:08:35 +0000146**
147** ^The sqlite3_compileoption_used() function returns 0 or 1
148** indicating whether the specified option was defined at
149** compile time. ^The SQLITE_ prefix may be omitted from the
150** option name passed to sqlite3_compileoption_used().
151**
152** ^The sqlite3_compileoption_get() function allows interating
153** over the list of options that were defined at compile time by
154** returning the N-th compile time option string. ^If N is out of range,
155** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
156** prefix is omitted from any strings returned by
157** sqlite3_compileoption_get().
158**
159** ^Support for the diagnostic functions sqlite3_compileoption_used()
160** and sqlite3_compileoption_get() may be omitted by specifing the
drh71caabf2010-02-26 15:39:24 +0000161** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
shanehdc97a8c2010-02-23 20:08:35 +0000162**
drh71caabf2010-02-26 15:39:24 +0000163** See also: SQL functions [sqlite_compileoption_used()] and
164** [sqlite_compileoption_get()] and the [compile_options pragma].
shanehdc97a8c2010-02-23 20:08:35 +0000165*/
dan98f0c362010-03-22 04:32:13 +0000166#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
shanehdc97a8c2010-02-23 20:08:35 +0000167int sqlite3_compileoption_used(const char *zOptName);
drh380083c2010-02-23 20:32:15 +0000168const char *sqlite3_compileoption_get(int N);
dan98f0c362010-03-22 04:32:13 +0000169#endif
drhefad9992004-06-22 12:13:55 +0000170
drh75897232000-05-29 14:26:00 +0000171/*
drhd68eee02009-12-11 03:44:18 +0000172** CAPI3REF: Test To See If The Library Is Threadsafe
173**
174** ^The sqlite3_threadsafe() function returns zero if and only if
175** SQLite was compiled mutexing code omitted due to the
176** [SQLITE_THREADSAFE] compile-time option being set to 0.
drhb67e8bf2007-08-30 20:09:48 +0000177**
drh33c1be32008-01-30 16:16:14 +0000178** SQLite can be compiled with or without mutexes. When
drh6aa5f152009-08-19 15:57:07 +0000179** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
drhafacce02008-09-02 21:35:03 +0000180** are enabled and SQLite is threadsafe. When the
181** [SQLITE_THREADSAFE] macro is 0,
drh33c1be32008-01-30 16:16:14 +0000182** the mutexes are omitted. Without the mutexes, it is not safe
mihailim362cc832008-06-21 06:16:42 +0000183** to use SQLite concurrently from more than one thread.
drhb67e8bf2007-08-30 20:09:48 +0000184**
mihailim362cc832008-06-21 06:16:42 +0000185** Enabling mutexes incurs a measurable performance penalty.
drh33c1be32008-01-30 16:16:14 +0000186** So if speed is of utmost importance, it makes sense to disable
187** the mutexes. But for maximum safety, mutexes should be enabled.
drhd68eee02009-12-11 03:44:18 +0000188** ^The default behavior is for mutexes to be enabled.
drh33c1be32008-01-30 16:16:14 +0000189**
drh6aa5f152009-08-19 15:57:07 +0000190** This interface can be used by an application to make sure that the
drh33c1be32008-01-30 16:16:14 +0000191** version of SQLite that it is linking against was compiled with
drh4766b292008-06-26 02:53:02 +0000192** the desired setting of the [SQLITE_THREADSAFE] macro.
193**
194** This interface only reports on the compile-time mutex setting
195** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
drhd68eee02009-12-11 03:44:18 +0000196** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
drh4766b292008-06-26 02:53:02 +0000197** can be fully or partially disabled using a call to [sqlite3_config()]
198** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
drhd68eee02009-12-11 03:44:18 +0000199** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
200** sqlite3_threadsafe() function shows only the compile-time setting of
201** thread safety, not any run-time changes to that setting made by
202** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
203** is unchanged by calls to sqlite3_config().)^
drh33c1be32008-01-30 16:16:14 +0000204**
drhafacce02008-09-02 21:35:03 +0000205** See the [threading mode] documentation for additional information.
drhb67e8bf2007-08-30 20:09:48 +0000206*/
207int sqlite3_threadsafe(void);
208
209/*
drhd68eee02009-12-11 03:44:18 +0000210** CAPI3REF: Database Connection Handle
drha06f17f2008-05-11 11:07:06 +0000211** KEYWORDS: {database connection} {database connections}
drh6ed48bf2007-06-14 20:57:18 +0000212**
mihailim362cc832008-06-21 06:16:42 +0000213** Each open SQLite database is represented by a pointer to an instance of
214** the opaque structure named "sqlite3". It is useful to think of an sqlite3
drh8bacf972007-08-25 16:21:29 +0000215** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
mihailim362cc832008-06-21 06:16:42 +0000216** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
217** is its destructor. There are many other interfaces (such as
218** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
219** [sqlite3_busy_timeout()] to name but three) that are methods on an
220** sqlite3 object.
drh75897232000-05-29 14:26:00 +0000221*/
222typedef struct sqlite3 sqlite3;
223
drh75897232000-05-29 14:26:00 +0000224/*
drhd68eee02009-12-11 03:44:18 +0000225** CAPI3REF: 64-Bit Integer Types
drh33c1be32008-01-30 16:16:14 +0000226** KEYWORDS: sqlite_int64 sqlite_uint64
drh6ed48bf2007-06-14 20:57:18 +0000227**
drh33c1be32008-01-30 16:16:14 +0000228** Because there is no cross-platform way to specify 64-bit integer types
drhfddfa2d2007-12-05 18:05:16 +0000229** SQLite includes typedefs for 64-bit signed and unsigned integers.
drh6ed48bf2007-06-14 20:57:18 +0000230**
mihailim362cc832008-06-21 06:16:42 +0000231** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
232** The sqlite_int64 and sqlite_uint64 types are supported for backwards
233** compatibility only.
drh33c1be32008-01-30 16:16:14 +0000234**
drhd68eee02009-12-11 03:44:18 +0000235** ^The sqlite3_int64 and sqlite_int64 types can store integer values
236** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
237** sqlite3_uint64 and sqlite_uint64 types can store integer values
238** between 0 and +18446744073709551615 inclusive.
drh75897232000-05-29 14:26:00 +0000239*/
drh27436af2006-03-28 23:57:17 +0000240#ifdef SQLITE_INT64_TYPE
drh9b8f4472006-04-04 01:54:55 +0000241 typedef SQLITE_INT64_TYPE sqlite_int64;
drh27436af2006-03-28 23:57:17 +0000242 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
243#elif defined(_MSC_VER) || defined(__BORLANDC__)
drh75897232000-05-29 14:26:00 +0000244 typedef __int64 sqlite_int64;
245 typedef unsigned __int64 sqlite_uint64;
246#else
247 typedef long long int sqlite_int64;
248 typedef unsigned long long int sqlite_uint64;
249#endif
drh6d2069d2007-08-14 01:58:53 +0000250typedef sqlite_int64 sqlite3_int64;
251typedef sqlite_uint64 sqlite3_uint64;
drh75897232000-05-29 14:26:00 +0000252
drhb37df7b2005-10-13 02:09:49 +0000253/*
254** If compiling for a processor that lacks floating point support,
mihailim362cc832008-06-21 06:16:42 +0000255** substitute integer for floating-point.
drhb37df7b2005-10-13 02:09:49 +0000256*/
257#ifdef SQLITE_OMIT_FLOATING_POINT
drh6d2069d2007-08-14 01:58:53 +0000258# define double sqlite3_int64
drhb37df7b2005-10-13 02:09:49 +0000259#endif
drh75897232000-05-29 14:26:00 +0000260
261/*
drhd68eee02009-12-11 03:44:18 +0000262** CAPI3REF: Closing A Database Connection
drh75897232000-05-29 14:26:00 +0000263**
drhd68eee02009-12-11 03:44:18 +0000264** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
265** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
266** successfullly destroyed and all associated resources are deallocated.
drh33c1be32008-01-30 16:16:14 +0000267**
drh7db29fb2009-10-20 14:23:09 +0000268** Applications must [sqlite3_finalize | finalize] all [prepared statements]
mihailim15194222008-06-22 09:55:14 +0000269** and [sqlite3_blob_close | close] all [BLOB handles] associated with
drhd68eee02009-12-11 03:44:18 +0000270** the [sqlite3] object prior to attempting to close the object. ^If
271** sqlite3_close() is called on a [database connection] that still has
272** outstanding [prepared statements] or [BLOB handles], then it returns
273** SQLITE_BUSY.
drh55b0cf02008-06-19 17:54:33 +0000274**
drhd68eee02009-12-11 03:44:18 +0000275** ^If [sqlite3_close()] is invoked while a transaction is open,
drh55b0cf02008-06-19 17:54:33 +0000276** the transaction is automatically rolled back.
drh33c1be32008-01-30 16:16:14 +0000277**
drh8b39db12009-02-18 18:37:58 +0000278** The C parameter to [sqlite3_close(C)] must be either a NULL
279** pointer or an [sqlite3] object pointer obtained
280** from [sqlite3_open()], [sqlite3_open16()], or
281** [sqlite3_open_v2()], and not previously closed.
drhd68eee02009-12-11 03:44:18 +0000282** ^Calling sqlite3_close() with a NULL pointer argument is a
283** harmless no-op.
drh75897232000-05-29 14:26:00 +0000284*/
danielk1977f9d64d22004-06-19 08:18:07 +0000285int sqlite3_close(sqlite3 *);
drh75897232000-05-29 14:26:00 +0000286
287/*
288** The type for a callback function.
drh6ed48bf2007-06-14 20:57:18 +0000289** This is legacy and deprecated. It is included for historical
290** compatibility and is not documented.
drh75897232000-05-29 14:26:00 +0000291*/
drh12057d52004-09-06 17:34:12 +0000292typedef int (*sqlite3_callback)(void*,int,char**, char**);
drh75897232000-05-29 14:26:00 +0000293
294/*
drhd68eee02009-12-11 03:44:18 +0000295** CAPI3REF: One-Step Query Execution Interface
drh6ed48bf2007-06-14 20:57:18 +0000296**
drhd68eee02009-12-11 03:44:18 +0000297** The sqlite3_exec() interface is a convenience wrapper around
298** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
299** that allows an application to run multiple statements of SQL
300** without having to use a lot of C code.
drh75897232000-05-29 14:26:00 +0000301**
drhd68eee02009-12-11 03:44:18 +0000302** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
303** semicolon-separate SQL statements passed into its 2nd argument,
304** in the context of the [database connection] passed in as its 1st
305** argument. ^If the callback function of the 3rd argument to
306** sqlite3_exec() is not NULL, then it is invoked for each result row
307** coming out of the evaluated SQL statements. ^The 4th argument to
308** to sqlite3_exec() is relayed through to the 1st argument of each
309** callback invocation. ^If the callback pointer to sqlite3_exec()
310** is NULL, then no callback is ever invoked and result rows are
311** ignored.
drh35c61902008-05-20 15:44:30 +0000312**
drhd68eee02009-12-11 03:44:18 +0000313** ^If an error occurs while evaluating the SQL statements passed into
314** sqlite3_exec(), then execution of the current statement stops and
315** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
316** is not NULL then any error message is written into memory obtained
317** from [sqlite3_malloc()] and passed back through the 5th parameter.
318** To avoid memory leaks, the application should invoke [sqlite3_free()]
319** on error message strings returned through the 5th parameter of
320** of sqlite3_exec() after the error message string is no longer needed.
321** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
322** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
323** NULL before returning.
drh35c61902008-05-20 15:44:30 +0000324**
drhd68eee02009-12-11 03:44:18 +0000325** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
326** routine returns SQLITE_ABORT without invoking the callback again and
327** without running any subsequent SQL statements.
drh75897232000-05-29 14:26:00 +0000328**
drhd68eee02009-12-11 03:44:18 +0000329** ^The 2nd argument to the sqlite3_exec() callback function is the
330** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
331** callback is an array of pointers to strings obtained as if from
332** [sqlite3_column_text()], one for each column. ^If an element of a
333** result row is NULL then the corresponding string pointer for the
334** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
335** sqlite3_exec() callback is an array of pointers to strings where each
336** entry represents the name of corresponding result column as obtained
337** from [sqlite3_column_name()].
mihailima3f64902008-06-21 13:35:56 +0000338**
drhd68eee02009-12-11 03:44:18 +0000339** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
340** to an empty string, or a pointer that contains only whitespace and/or
341** SQL comments, then no SQL statements are evaluated and the database
342** is not changed.
drh75897232000-05-29 14:26:00 +0000343**
drhd68eee02009-12-11 03:44:18 +0000344** Restrictions:
drh75897232000-05-29 14:26:00 +0000345**
drhd68eee02009-12-11 03:44:18 +0000346** <ul>
347** <li> The application must insure that the 1st parameter to sqlite3_exec()
348** is a valid and open [database connection].
349** <li> The application must not close [database connection] specified by
350** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
351** <li> The application must not modify the SQL statement text passed into
352** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
353** </ul>
drh75897232000-05-29 14:26:00 +0000354*/
danielk19776f8a5032004-05-10 10:34:51 +0000355int sqlite3_exec(
drh6ed48bf2007-06-14 20:57:18 +0000356 sqlite3*, /* An open database */
shane236ce972008-05-30 15:35:30 +0000357 const char *sql, /* SQL to be evaluated */
drh6ed48bf2007-06-14 20:57:18 +0000358 int (*callback)(void*,int,char**,char**), /* Callback function */
359 void *, /* 1st argument to callback */
360 char **errmsg /* Error msg written here */
drh75897232000-05-29 14:26:00 +0000361);
362
drh58b95762000-06-02 01:17:37 +0000363/*
drhd68eee02009-12-11 03:44:18 +0000364** CAPI3REF: Result Codes
drh33c1be32008-01-30 16:16:14 +0000365** KEYWORDS: SQLITE_OK {error code} {error codes}
mihailimefc8e8a2008-06-21 16:47:09 +0000366** KEYWORDS: {result code} {result codes}
drh6ed48bf2007-06-14 20:57:18 +0000367**
368** Many SQLite functions return an integer result code from the set shown
drh33c1be32008-01-30 16:16:14 +0000369** here in order to indicates success or failure.
drh6ed48bf2007-06-14 20:57:18 +0000370**
drh4766b292008-06-26 02:53:02 +0000371** New error codes may be added in future versions of SQLite.
372**
drh6ed48bf2007-06-14 20:57:18 +0000373** See also: [SQLITE_IOERR_READ | extended result codes]
drh58b95762000-06-02 01:17:37 +0000374*/
drh717e6402001-09-27 03:22:32 +0000375#define SQLITE_OK 0 /* Successful result */
drh15b9a152006-01-31 20:49:13 +0000376/* beginning-of-error-codes */
drh717e6402001-09-27 03:22:32 +0000377#define SQLITE_ERROR 1 /* SQL error or missing database */
drh89e0dde2007-12-12 12:25:21 +0000378#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
drh717e6402001-09-27 03:22:32 +0000379#define SQLITE_PERM 3 /* Access permission denied */
380#define SQLITE_ABORT 4 /* Callback routine requested an abort */
381#define SQLITE_BUSY 5 /* The database file is locked */
382#define SQLITE_LOCKED 6 /* A table in the database is locked */
383#define SQLITE_NOMEM 7 /* A malloc() failed */
384#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
drh24cd67e2004-05-10 16:18:47 +0000385#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
drh717e6402001-09-27 03:22:32 +0000386#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
387#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
drh2db0bbc2005-08-11 02:10:18 +0000388#define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */
drh717e6402001-09-27 03:22:32 +0000389#define SQLITE_FULL 13 /* Insertion failed because database is full */
390#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
drhaab4c022010-06-02 14:45:51 +0000391#define SQLITE_PROTOCOL 15 /* Database lock protocol error */
drh24cd67e2004-05-10 16:18:47 +0000392#define SQLITE_EMPTY 16 /* Database is empty */
drh717e6402001-09-27 03:22:32 +0000393#define SQLITE_SCHEMA 17 /* The database schema changed */
drhc797d4d2007-05-08 01:08:49 +0000394#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
danielk19776eb91d22007-09-21 04:27:02 +0000395#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
drh8aff1012001-12-22 14:49:24 +0000396#define SQLITE_MISMATCH 20 /* Data type mismatch */
drh247be432002-05-10 05:44:55 +0000397#define SQLITE_MISUSE 21 /* Library used incorrectly */
drh8766c342002-11-09 00:33:15 +0000398#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
drhed6c8672003-01-12 18:02:16 +0000399#define SQLITE_AUTH 23 /* Authorization denied */
drh1c2d8412003-03-31 00:30:47 +0000400#define SQLITE_FORMAT 24 /* Auxiliary database format error */
danielk19776f8a5032004-05-10 10:34:51 +0000401#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
drhc602f9a2004-02-12 19:01:04 +0000402#define SQLITE_NOTADB 26 /* File opened that is not a database file */
danielk19776f8a5032004-05-10 10:34:51 +0000403#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
404#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
drh15b9a152006-01-31 20:49:13 +0000405/* end-of-error-codes */
drh717e6402001-09-27 03:22:32 +0000406
drhaf9ff332002-01-16 21:00:27 +0000407/*
drhd68eee02009-12-11 03:44:18 +0000408** CAPI3REF: Extended Result Codes
drh33c1be32008-01-30 16:16:14 +0000409** KEYWORDS: {extended error code} {extended error codes}
mihailimefc8e8a2008-06-21 16:47:09 +0000410** KEYWORDS: {extended result code} {extended result codes}
drh4ac285a2006-09-15 07:28:50 +0000411**
drh6ed48bf2007-06-14 20:57:18 +0000412** In its default configuration, SQLite API routines return one of 26 integer
mihailim362cc832008-06-21 06:16:42 +0000413** [SQLITE_OK | result codes]. However, experience has shown that many of
414** these result codes are too coarse-grained. They do not provide as
drhf5befa02007-12-06 02:42:07 +0000415** much information about problems as programmers might like. In an effort to
drh6ed48bf2007-06-14 20:57:18 +0000416** address this, newer versions of SQLite (version 3.3.8 and later) include
417** support for additional result codes that provide more detailed information
drh33c1be32008-01-30 16:16:14 +0000418** about errors. The extended result codes are enabled or disabled
mihailim362cc832008-06-21 06:16:42 +0000419** on a per database connection basis using the
420** [sqlite3_extended_result_codes()] API.
mihailima3f64902008-06-21 13:35:56 +0000421**
drh33c1be32008-01-30 16:16:14 +0000422** Some of the available extended result codes are listed here.
423** One may expect the number of extended result codes will be expand
424** over time. Software that uses extended result codes should expect
425** to see new result codes in future releases of SQLite.
drh4ac285a2006-09-15 07:28:50 +0000426**
427** The SQLITE_OK result code will never be extended. It will always
428** be exactly zero.
drh4ac285a2006-09-15 07:28:50 +0000429*/
danielk1977861f7452008-06-05 11:39:11 +0000430#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
431#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
432#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
433#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
434#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
435#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
436#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
437#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
438#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
439#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
440#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
441#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
442#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
443#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
aswift5b1a2562008-08-22 00:22:35 +0000444#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
aswiftaebf4132008-11-21 00:10:35 +0000445#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
446#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
drhaab4c022010-06-02 14:45:51 +0000447#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
448#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
449#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
drh73b64e42010-05-30 19:55:15 +0000450#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
451#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
drh8b3cf822010-06-01 21:02:51 +0000452#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
danielk1977404ca072009-03-16 13:19:36 +0000453
drh4ac285a2006-09-15 07:28:50 +0000454/*
drhd68eee02009-12-11 03:44:18 +0000455** CAPI3REF: Flags For File Open Operations
drh6d2069d2007-08-14 01:58:53 +0000456**
mlcreechb2799412008-03-07 03:20:31 +0000457** These bit values are intended for use in the
drh33c1be32008-01-30 16:16:14 +0000458** 3rd parameter to the [sqlite3_open_v2()] interface and
459** in the 4th parameter to the xOpen method of the
drhd84f9462007-08-15 11:28:56 +0000460** [sqlite3_vfs] object.
drh6d2069d2007-08-14 01:58:53 +0000461*/
shane089b0a42009-05-14 03:21:28 +0000462#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
463#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
464#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
465#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
466#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
drh7ed97b92010-01-20 13:07:21 +0000467#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
shane089b0a42009-05-14 03:21:28 +0000468#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
469#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
470#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
471#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
472#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
473#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
474#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
475#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
476#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
drhf1f12682009-09-09 14:17:52 +0000477#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
478#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
drh6d2069d2007-08-14 01:58:53 +0000479
480/*
drhd68eee02009-12-11 03:44:18 +0000481** CAPI3REF: Device Characteristics
drh6d2069d2007-08-14 01:58:53 +0000482**
drh33c1be32008-01-30 16:16:14 +0000483** The xDeviceCapabilities method of the [sqlite3_io_methods]
drhfddfa2d2007-12-05 18:05:16 +0000484** object returns an integer which is a vector of the these
drh6d2069d2007-08-14 01:58:53 +0000485** bit values expressing I/O characteristics of the mass storage
486** device that holds the file that the [sqlite3_io_methods]
drh33c1be32008-01-30 16:16:14 +0000487** refers to.
drh6d2069d2007-08-14 01:58:53 +0000488**
drh33c1be32008-01-30 16:16:14 +0000489** The SQLITE_IOCAP_ATOMIC property means that all writes of
490** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
drh6d2069d2007-08-14 01:58:53 +0000491** mean that writes of blocks that are nnn bytes in size and
492** are aligned to an address which is an integer multiple of
drh33c1be32008-01-30 16:16:14 +0000493** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
drh6d2069d2007-08-14 01:58:53 +0000494** that when data is appended to a file, the data is appended
495** first then the size of the file is extended, never the other
drh33c1be32008-01-30 16:16:14 +0000496** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
drh6d2069d2007-08-14 01:58:53 +0000497** information is written to disk in the same order as calls
498** to xWrite().
499*/
dan8ce49d62010-06-19 18:12:02 +0000500#define SQLITE_IOCAP_ATOMIC 0x00000001
501#define SQLITE_IOCAP_ATOMIC512 0x00000002
502#define SQLITE_IOCAP_ATOMIC1K 0x00000004
503#define SQLITE_IOCAP_ATOMIC2K 0x00000008
504#define SQLITE_IOCAP_ATOMIC4K 0x00000010
505#define SQLITE_IOCAP_ATOMIC8K 0x00000020
506#define SQLITE_IOCAP_ATOMIC16K 0x00000040
507#define SQLITE_IOCAP_ATOMIC32K 0x00000080
508#define SQLITE_IOCAP_ATOMIC64K 0x00000100
509#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
510#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
511#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
drh6d2069d2007-08-14 01:58:53 +0000512
513/*
drhd68eee02009-12-11 03:44:18 +0000514** CAPI3REF: File Locking Levels
drh6d2069d2007-08-14 01:58:53 +0000515**
drh33c1be32008-01-30 16:16:14 +0000516** SQLite uses one of these integer values as the second
drh6d2069d2007-08-14 01:58:53 +0000517** argument to calls it makes to the xLock() and xUnlock() methods
drh33c1be32008-01-30 16:16:14 +0000518** of an [sqlite3_io_methods] object.
drh6d2069d2007-08-14 01:58:53 +0000519*/
520#define SQLITE_LOCK_NONE 0
521#define SQLITE_LOCK_SHARED 1
522#define SQLITE_LOCK_RESERVED 2
523#define SQLITE_LOCK_PENDING 3
524#define SQLITE_LOCK_EXCLUSIVE 4
525
526/*
drhd68eee02009-12-11 03:44:18 +0000527** CAPI3REF: Synchronization Type Flags
drh6d2069d2007-08-14 01:58:53 +0000528**
drh33c1be32008-01-30 16:16:14 +0000529** When SQLite invokes the xSync() method of an
mlcreechb2799412008-03-07 03:20:31 +0000530** [sqlite3_io_methods] object it uses a combination of
drhfddfa2d2007-12-05 18:05:16 +0000531** these integer values as the second argument.
drh6d2069d2007-08-14 01:58:53 +0000532**
drh33c1be32008-01-30 16:16:14 +0000533** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
drh6d2069d2007-08-14 01:58:53 +0000534** sync operation only needs to flush data to mass storage. Inode
drheb0d6292009-04-04 14:04:58 +0000535** information need not be flushed. If the lower four bits of the flag
536** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
537** If the lower four bits equal SQLITE_SYNC_FULL, that means
shane7ba429a2008-11-10 17:08:49 +0000538** to use Mac OS X style fullsync instead of fsync().
drh6d2069d2007-08-14 01:58:53 +0000539*/
drh6d2069d2007-08-14 01:58:53 +0000540#define SQLITE_SYNC_NORMAL 0x00002
541#define SQLITE_SYNC_FULL 0x00003
542#define SQLITE_SYNC_DATAONLY 0x00010
543
drh6d2069d2007-08-14 01:58:53 +0000544/*
drhd68eee02009-12-11 03:44:18 +0000545** CAPI3REF: OS Interface Open File Handle
drh6d2069d2007-08-14 01:58:53 +0000546**
drh6aa5f152009-08-19 15:57:07 +0000547** An [sqlite3_file] object represents an open file in the
548** [sqlite3_vfs | OS interface layer]. Individual OS interface
549** implementations will
drh6d2069d2007-08-14 01:58:53 +0000550** want to subclass this object by appending additional fields
drh4ff7fa02007-09-01 18:17:21 +0000551** for their own use. The pMethods entry is a pointer to an
drhd84f9462007-08-15 11:28:56 +0000552** [sqlite3_io_methods] object that defines methods for performing
553** I/O operations on the open file.
drh6d2069d2007-08-14 01:58:53 +0000554*/
555typedef struct sqlite3_file sqlite3_file;
556struct sqlite3_file {
drh153c62c2007-08-24 03:51:33 +0000557 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
drh6d2069d2007-08-14 01:58:53 +0000558};
559
560/*
drhd68eee02009-12-11 03:44:18 +0000561** CAPI3REF: OS Interface File Virtual Methods Object
drh6d2069d2007-08-14 01:58:53 +0000562**
drh4766b292008-06-26 02:53:02 +0000563** Every file opened by the [sqlite3_vfs] xOpen method populates an
564** [sqlite3_file] object (or, more commonly, a subclass of the
565** [sqlite3_file] object) with a pointer to an instance of this object.
566** This object defines the methods used to perform various operations
567** against the open file represented by the [sqlite3_file] object.
drhd84f9462007-08-15 11:28:56 +0000568**
drh9afedcc2009-06-19 22:50:31 +0000569** If the xOpen method sets the sqlite3_file.pMethods element
570** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
571** may be invoked even if the xOpen reported that it failed. The
572** only way to prevent a call to xClose following a failed xOpen
573** is for the xOpen to set the sqlite3_file.pMethods element to NULL.
574**
drhfddfa2d2007-12-05 18:05:16 +0000575** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
576** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
shane7ba429a2008-11-10 17:08:49 +0000577** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
mihailim362cc832008-06-21 06:16:42 +0000578** flag may be ORed in to indicate that only the data of the file
579** and not its inode needs to be synced.
mihailima3f64902008-06-21 13:35:56 +0000580**
drhd84f9462007-08-15 11:28:56 +0000581** The integer values to xLock() and xUnlock() are one of
drh4ff7fa02007-09-01 18:17:21 +0000582** <ul>
583** <li> [SQLITE_LOCK_NONE],
drh79491ab2007-09-04 12:00:00 +0000584** <li> [SQLITE_LOCK_SHARED],
drh4ff7fa02007-09-01 18:17:21 +0000585** <li> [SQLITE_LOCK_RESERVED],
586** <li> [SQLITE_LOCK_PENDING], or
587** <li> [SQLITE_LOCK_EXCLUSIVE].
588** </ul>
mihailima3f64902008-06-21 13:35:56 +0000589** xLock() increases the lock. xUnlock() decreases the lock.
mihailim362cc832008-06-21 06:16:42 +0000590** The xCheckReservedLock() method checks whether any database connection,
591** either in this process or in some other process, is holding a RESERVED,
drhd84f9462007-08-15 11:28:56 +0000592** PENDING, or EXCLUSIVE lock on the file. It returns true
mihailim362cc832008-06-21 06:16:42 +0000593** if such a lock exists and false otherwise.
mihailima3f64902008-06-21 13:35:56 +0000594**
drhcc6bb3e2007-08-31 16:11:35 +0000595** The xFileControl() method is a generic interface that allows custom
596** VFS implementations to directly control an open file using the
mihailim362cc832008-06-21 06:16:42 +0000597** [sqlite3_file_control()] interface. The second "op" argument is an
mihailima3f64902008-06-21 13:35:56 +0000598** integer opcode. The third argument is a generic pointer intended to
mihailim362cc832008-06-21 06:16:42 +0000599** point to a structure that may contain arguments or space in which to
drhcc6bb3e2007-08-31 16:11:35 +0000600** write return values. Potential uses for xFileControl() might be
601** functions to enable blocking locks with timeouts, to change the
602** locking strategy (for example to use dot-file locks), to inquire
drh9e33c2c2007-08-31 18:34:59 +0000603** about the status of a lock, or to break stale locks. The SQLite
mihailima3f64902008-06-21 13:35:56 +0000604** core reserves all opcodes less than 100 for its own use.
drh4ff7fa02007-09-01 18:17:21 +0000605** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
mihailim362cc832008-06-21 06:16:42 +0000606** Applications that define a custom xFileControl method should use opcodes
drh9e33c2c2007-08-31 18:34:59 +0000607** greater than 100 to avoid conflicts.
drhd84f9462007-08-15 11:28:56 +0000608**
609** The xSectorSize() method returns the sector size of the
610** device that underlies the file. The sector size is the
611** minimum write that can be performed without disturbing
612** other bytes in the file. The xDeviceCharacteristics()
613** method returns a bit vector describing behaviors of the
614** underlying device:
615**
616** <ul>
drh4ff7fa02007-09-01 18:17:21 +0000617** <li> [SQLITE_IOCAP_ATOMIC]
618** <li> [SQLITE_IOCAP_ATOMIC512]
619** <li> [SQLITE_IOCAP_ATOMIC1K]
620** <li> [SQLITE_IOCAP_ATOMIC2K]
621** <li> [SQLITE_IOCAP_ATOMIC4K]
622** <li> [SQLITE_IOCAP_ATOMIC8K]
623** <li> [SQLITE_IOCAP_ATOMIC16K]
624** <li> [SQLITE_IOCAP_ATOMIC32K]
625** <li> [SQLITE_IOCAP_ATOMIC64K]
626** <li> [SQLITE_IOCAP_SAFE_APPEND]
627** <li> [SQLITE_IOCAP_SEQUENTIAL]
drhd84f9462007-08-15 11:28:56 +0000628** </ul>
629**
630** The SQLITE_IOCAP_ATOMIC property means that all writes of
631** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
632** mean that writes of blocks that are nnn bytes in size and
633** are aligned to an address which is an integer multiple of
634** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
635** that when data is appended to a file, the data is appended
636** first then the size of the file is extended, never the other
637** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
638** information is written to disk in the same order as calls
639** to xWrite().
drh4c17c3f2008-11-07 00:06:18 +0000640**
641** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
642** in the unread portions of the buffer with zeros. A VFS that
643** fails to zero-fill short reads might seem to work. However,
644** failure to zero-fill short reads will eventually lead to
645** database corruption.
drh6d2069d2007-08-14 01:58:53 +0000646*/
647typedef struct sqlite3_io_methods sqlite3_io_methods;
648struct sqlite3_io_methods {
649 int iVersion;
650 int (*xClose)(sqlite3_file*);
drh79491ab2007-09-04 12:00:00 +0000651 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
652 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
653 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
drh6d2069d2007-08-14 01:58:53 +0000654 int (*xSync)(sqlite3_file*, int flags);
drh79491ab2007-09-04 12:00:00 +0000655 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
drh6d2069d2007-08-14 01:58:53 +0000656 int (*xLock)(sqlite3_file*, int);
657 int (*xUnlock)(sqlite3_file*, int);
danielk1977861f7452008-06-05 11:39:11 +0000658 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
drhcc6bb3e2007-08-31 16:11:35 +0000659 int (*xFileControl)(sqlite3_file*, int op, void *pArg);
drh6d2069d2007-08-14 01:58:53 +0000660 int (*xSectorSize)(sqlite3_file*);
661 int (*xDeviceCharacteristics)(sqlite3_file*);
drhd9e5c4f2010-05-12 18:01:39 +0000662 /* Methods above are valid for version 1 */
663 int (*xShmOpen)(sqlite3_file*);
drh73b64e42010-05-30 19:55:15 +0000664 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
drh6b017cc2010-06-14 18:01:46 +0000665 int (*xShmMap)(sqlite3_file*, int iPage, int pgsz, int, void volatile**);
drh286a2882010-05-20 23:51:06 +0000666 void (*xShmBarrier)(sqlite3_file*);
drhd9e5c4f2010-05-12 18:01:39 +0000667 int (*xShmClose)(sqlite3_file*, int deleteFlag);
668 /* Methods above are valid for version 2 */
drh6d2069d2007-08-14 01:58:53 +0000669 /* Additional methods may be added in future releases */
670};
671
672/*
drhd68eee02009-12-11 03:44:18 +0000673** CAPI3REF: Standard File Control Opcodes
drh9e33c2c2007-08-31 18:34:59 +0000674**
675** These integer constants are opcodes for the xFileControl method
mihailim362cc832008-06-21 06:16:42 +0000676** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
drh9e33c2c2007-08-31 18:34:59 +0000677** interface.
678**
drh33c1be32008-01-30 16:16:14 +0000679** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
mlcreechb2799412008-03-07 03:20:31 +0000680** opcode causes the xFileControl method to write the current state of
drh9e33c2c2007-08-31 18:34:59 +0000681** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
682** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
drh33c1be32008-01-30 16:16:14 +0000683** into an integer that the pArg argument points to. This capability
drh9e33c2c2007-08-31 18:34:59 +0000684** is used during testing and only needs to be supported when SQLITE_TEST
685** is defined.
drh9ff27ec2010-05-19 19:26:05 +0000686**
687** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
688** layer a hint of how large the database file will grow to be during the
689** current transaction. This hint is not guaranteed to be accurate but it
690** is often close. The underlying VFS might choose to preallocate database
691** file space based on this hint in order to help writes to the database
692** file run faster.
drh9e33c2c2007-08-31 18:34:59 +0000693*/
694#define SQLITE_FCNTL_LOCKSTATE 1
aswiftaebf4132008-11-21 00:10:35 +0000695#define SQLITE_GET_LOCKPROXYFILE 2
696#define SQLITE_SET_LOCKPROXYFILE 3
697#define SQLITE_LAST_ERRNO 4
drh9ff27ec2010-05-19 19:26:05 +0000698#define SQLITE_FCNTL_SIZE_HINT 5
drh9e33c2c2007-08-31 18:34:59 +0000699
700/*
drhd68eee02009-12-11 03:44:18 +0000701** CAPI3REF: Mutex Handle
drh6d2069d2007-08-14 01:58:53 +0000702**
drhd84f9462007-08-15 11:28:56 +0000703** The mutex module within SQLite defines [sqlite3_mutex] to be an
drh33c1be32008-01-30 16:16:14 +0000704** abstract type for a mutex object. The SQLite core never looks
705** at the internal representation of an [sqlite3_mutex]. It only
drhd84f9462007-08-15 11:28:56 +0000706** deals with pointers to the [sqlite3_mutex] object.
drh6bdec4a2007-08-16 19:40:16 +0000707**
708** Mutexes are created using [sqlite3_mutex_alloc()].
drh6d2069d2007-08-14 01:58:53 +0000709*/
710typedef struct sqlite3_mutex sqlite3_mutex;
711
712/*
drhd68eee02009-12-11 03:44:18 +0000713** CAPI3REF: OS Interface Object
drh6d2069d2007-08-14 01:58:53 +0000714**
mihailim362cc832008-06-21 06:16:42 +0000715** An instance of the sqlite3_vfs object defines the interface between
716** the SQLite core and the underlying operating system. The "vfs"
drhd84f9462007-08-15 11:28:56 +0000717** in the name of the object stands for "virtual file system".
drh6d2069d2007-08-14 01:58:53 +0000718**
mihailim362cc832008-06-21 06:16:42 +0000719** The value of the iVersion field is initially 1 but may be larger in
720** future versions of SQLite. Additional fields may be appended to this
drh4766b292008-06-26 02:53:02 +0000721** object when the iVersion value is increased. Note that the structure
722** of the sqlite3_vfs object changes in the transaction between
723** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
724** modified.
drh6bdec4a2007-08-16 19:40:16 +0000725**
drh4ff7fa02007-09-01 18:17:21 +0000726** The szOsFile field is the size of the subclassed [sqlite3_file]
drhd84f9462007-08-15 11:28:56 +0000727** structure used by this VFS. mxPathname is the maximum length of
728** a pathname in this VFS.
729**
drhb4d58ae2008-02-21 20:17:06 +0000730** Registered sqlite3_vfs objects are kept on a linked list formed by
drh79491ab2007-09-04 12:00:00 +0000731** the pNext pointer. The [sqlite3_vfs_register()]
732** and [sqlite3_vfs_unregister()] interfaces manage this list
733** in a thread-safe way. The [sqlite3_vfs_find()] interface
drh4766b292008-06-26 02:53:02 +0000734** searches the list. Neither the application code nor the VFS
735** implementation should use the pNext pointer.
drhd84f9462007-08-15 11:28:56 +0000736**
mihailima3f64902008-06-21 13:35:56 +0000737** The pNext field is the only field in the sqlite3_vfs
drh1cc8c442007-08-24 16:08:29 +0000738** structure that SQLite will ever modify. SQLite will only access
739** or modify this field while holding a particular static mutex.
740** The application should never modify anything within the sqlite3_vfs
741** object once the object has been registered.
742**
drhd84f9462007-08-15 11:28:56 +0000743** The zName field holds the name of the VFS module. The name must
744** be unique across all VFS modules.
745**
drh032ca702008-12-10 11:44:30 +0000746** SQLite will guarantee that the zFilename parameter to xOpen
drh4766b292008-06-26 02:53:02 +0000747** is either a NULL pointer or string obtained
748** from xFullPathname(). SQLite further guarantees that
749** the string will be valid and unchanged until xClose() is
drh9afedcc2009-06-19 22:50:31 +0000750** called. Because of the previous sentence,
drh4766b292008-06-26 02:53:02 +0000751** the [sqlite3_file] can safely store a pointer to the
drh6d2069d2007-08-14 01:58:53 +0000752** filename if it needs to remember the filename for some reason.
drh4766b292008-06-26 02:53:02 +0000753** If the zFilename parameter is xOpen is a NULL pointer then xOpen
drh9afedcc2009-06-19 22:50:31 +0000754** must invent its own temporary name for the file. Whenever the
drh4766b292008-06-26 02:53:02 +0000755** xFilename parameter is NULL it will also be the case that the
756** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
drhd84f9462007-08-15 11:28:56 +0000757**
drh032ca702008-12-10 11:44:30 +0000758** The flags argument to xOpen() includes all bits set in
drhf5befa02007-12-06 02:42:07 +0000759** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
760** or [sqlite3_open16()] is used, then flags includes at least
drh032ca702008-12-10 11:44:30 +0000761** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
drh6d2069d2007-08-14 01:58:53 +0000762** If xOpen() opens a file read-only then it sets *pOutFlags to
mihailim362cc832008-06-21 06:16:42 +0000763** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
764**
drh032ca702008-12-10 11:44:30 +0000765** SQLite will also add one of the following flags to the xOpen()
drh6d2069d2007-08-14 01:58:53 +0000766** call, depending on the object being opened:
mihailim362cc832008-06-21 06:16:42 +0000767**
drh6d2069d2007-08-14 01:58:53 +0000768** <ul>
769** <li> [SQLITE_OPEN_MAIN_DB]
770** <li> [SQLITE_OPEN_MAIN_JOURNAL]
771** <li> [SQLITE_OPEN_TEMP_DB]
772** <li> [SQLITE_OPEN_TEMP_JOURNAL]
drh33f4e022007-09-03 15:19:34 +0000773** <li> [SQLITE_OPEN_TRANSIENT_DB]
drh6d2069d2007-08-14 01:58:53 +0000774** <li> [SQLITE_OPEN_SUBJOURNAL]
775** <li> [SQLITE_OPEN_MASTER_JOURNAL]
drh032ca702008-12-10 11:44:30 +0000776** </ul>
drhd84f9462007-08-15 11:28:56 +0000777**
drh6d2069d2007-08-14 01:58:53 +0000778** The file I/O implementation can use the object type flags to
mihailim362cc832008-06-21 06:16:42 +0000779** change the way it deals with files. For example, an application
mlcreechb2799412008-03-07 03:20:31 +0000780** that does not care about crash recovery or rollback might make
781** the open of a journal file a no-op. Writes to this journal would
mihailim362cc832008-06-21 06:16:42 +0000782** also be no-ops, and any attempt to read the journal would return
783** SQLITE_IOERR. Or the implementation might recognize that a database
784** file will be doing page-aligned sector reads and writes in a random
mlcreechb2799412008-03-07 03:20:31 +0000785** order and set up its I/O subsystem accordingly.
mihailim362cc832008-06-21 06:16:42 +0000786**
787** SQLite might also add one of the following flags to the xOpen method:
788**
drh6d2069d2007-08-14 01:58:53 +0000789** <ul>
790** <li> [SQLITE_OPEN_DELETEONCLOSE]
791** <li> [SQLITE_OPEN_EXCLUSIVE]
792** </ul>
mihailim362cc832008-06-21 06:16:42 +0000793**
drh032ca702008-12-10 11:44:30 +0000794** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
795** deleted when it is closed. The [SQLITE_OPEN_DELETEONCLOSE]
mihailim362cc832008-06-21 06:16:42 +0000796** will be set for TEMP databases, journals and for subjournals.
mihailim04bcc002008-06-22 10:21:27 +0000797**
shane089b0a42009-05-14 03:21:28 +0000798** The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
799** with the [SQLITE_OPEN_CREATE] flag, which are both directly
800** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
801** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
802** SQLITE_OPEN_CREATE, is used to indicate that file should always
803** be created, and that it is an error if it already exists.
804** It is <i>not</i> used to indicate the file should be opened
805** for exclusive access.
mihailim362cc832008-06-21 06:16:42 +0000806**
drh032ca702008-12-10 11:44:30 +0000807** At least szOsFile bytes of memory are allocated by SQLite
mihailim362cc832008-06-21 06:16:42 +0000808** to hold the [sqlite3_file] structure passed as the third
drh032ca702008-12-10 11:44:30 +0000809** argument to xOpen. The xOpen method does not have to
drh9afedcc2009-06-19 22:50:31 +0000810** allocate the structure; it should just fill it in. Note that
811** the xOpen method must set the sqlite3_file.pMethods to either
812** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
813** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
814** element will be valid after xOpen returns regardless of the success
815** or failure of the xOpen call.
mihailim362cc832008-06-21 06:16:42 +0000816**
drh032ca702008-12-10 11:44:30 +0000817** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
mihailim362cc832008-06-21 06:16:42 +0000818** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
819** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
drh032ca702008-12-10 11:44:30 +0000820** to test whether a file is at least readable. The file can be a
drh6d2069d2007-08-14 01:58:53 +0000821** directory.
mihailim362cc832008-06-21 06:16:42 +0000822**
drh032ca702008-12-10 11:44:30 +0000823** SQLite will always allocate at least mxPathname+1 bytes for the
824** output buffer xFullPathname. The exact size of the output buffer
825** is also passed as a parameter to both methods. If the output buffer
mihailim362cc832008-06-21 06:16:42 +0000826** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
827** handled as a fatal error by SQLite, vfs implementations should endeavor
828** to prevent this by setting mxPathname to a sufficiently large value.
829**
drhd84f9462007-08-15 11:28:56 +0000830** The xRandomness(), xSleep(), and xCurrentTime() interfaces
831** are not strictly a part of the filesystem, but they are
832** included in the VFS structure for completeness.
drh6d2069d2007-08-14 01:58:53 +0000833** The xRandomness() function attempts to return nBytes bytes
834** of good-quality randomness into zOut. The return value is
mihailim362cc832008-06-21 06:16:42 +0000835** the actual number of bytes of randomness obtained.
836** The xSleep() method causes the calling thread to sleep for at
drhd84f9462007-08-15 11:28:56 +0000837** least the number of microseconds given. The xCurrentTime()
mihailim362cc832008-06-21 06:16:42 +0000838** method returns a Julian Day Number for the current date and time.
drh032ca702008-12-10 11:44:30 +0000839**
drh6d2069d2007-08-14 01:58:53 +0000840*/
drhd84f9462007-08-15 11:28:56 +0000841typedef struct sqlite3_vfs sqlite3_vfs;
842struct sqlite3_vfs {
drhf2424c52010-04-26 00:04:55 +0000843 int iVersion; /* Structure version number (currently 2) */
drh6d2069d2007-08-14 01:58:53 +0000844 int szOsFile; /* Size of subclassed sqlite3_file */
drh6d2069d2007-08-14 01:58:53 +0000845 int mxPathname; /* Maximum file pathname length */
drhd84f9462007-08-15 11:28:56 +0000846 sqlite3_vfs *pNext; /* Next registered VFS */
drhd84f9462007-08-15 11:28:56 +0000847 const char *zName; /* Name of this virtual file system */
drh1cc8c442007-08-24 16:08:29 +0000848 void *pAppData; /* Pointer to application-specific data */
drh153c62c2007-08-24 03:51:33 +0000849 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
drh6d2069d2007-08-14 01:58:53 +0000850 int flags, int *pOutFlags);
drh153c62c2007-08-24 03:51:33 +0000851 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
danielk1977861f7452008-06-05 11:39:11 +0000852 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
danielk1977adfb9b02007-09-17 07:02:56 +0000853 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
drh153c62c2007-08-24 03:51:33 +0000854 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
855 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
drh1875f7a2008-12-08 18:19:17 +0000856 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
drh153c62c2007-08-24 03:51:33 +0000857 void (*xDlClose)(sqlite3_vfs*, void*);
858 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
859 int (*xSleep)(sqlite3_vfs*, int microseconds);
860 int (*xCurrentTime)(sqlite3_vfs*, double*);
danielk1977bcb97fe2008-06-06 15:49:29 +0000861 int (*xGetLastError)(sqlite3_vfs*, int, char *);
drhf2424c52010-04-26 00:04:55 +0000862 /*
863 ** The methods above are in version 1 of the sqlite_vfs object
864 ** definition. Those that follow are added in version 2 or later
865 */
drhf2424c52010-04-26 00:04:55 +0000866 int (*xRename)(sqlite3_vfs*, const char *zOld, const char *zNew, int dirSync);
867 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
868 /*
869 ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
870 ** New fields may be appended in figure versions. The iVersion
871 ** value will increment whenever this happens.
872 */
drh6d2069d2007-08-14 01:58:53 +0000873};
874
drh50d3f902007-08-27 21:10:36 +0000875/*
drhd68eee02009-12-11 03:44:18 +0000876** CAPI3REF: Flags for the xAccess VFS method
drh50d3f902007-08-27 21:10:36 +0000877**
drh032ca702008-12-10 11:44:30 +0000878** These integer constants can be used as the third parameter to
drhfb434032009-12-11 23:11:26 +0000879** the xAccess method of an [sqlite3_vfs] object. They determine
mihailim04bcc002008-06-22 10:21:27 +0000880** what kind of permissions the xAccess method is looking for.
drh032ca702008-12-10 11:44:30 +0000881** With SQLITE_ACCESS_EXISTS, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000882** simply checks whether the file exists.
drh032ca702008-12-10 11:44:30 +0000883** With SQLITE_ACCESS_READWRITE, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000884** checks whether the file is both readable and writable.
drh032ca702008-12-10 11:44:30 +0000885** With SQLITE_ACCESS_READ, the xAccess method
mihailim04bcc002008-06-22 10:21:27 +0000886** checks whether the file is readable.
drh50d3f902007-08-27 21:10:36 +0000887*/
danielk1977b4b47412007-08-17 15:53:36 +0000888#define SQLITE_ACCESS_EXISTS 0
889#define SQLITE_ACCESS_READWRITE 1
drh50d3f902007-08-27 21:10:36 +0000890#define SQLITE_ACCESS_READ 2
danielk1977b4b47412007-08-17 15:53:36 +0000891
drh6d2069d2007-08-14 01:58:53 +0000892/*
drhf2424c52010-04-26 00:04:55 +0000893** CAPI3REF: Flags for the xShmLock VFS method
894**
drh73b64e42010-05-30 19:55:15 +0000895** These integer constants define the various locking operations
896** allowed by the xShmLock method of [sqlite3_io_methods]. The
897** following are the only legal combinations of flags to the
898** xShmLock method:
899**
900** <ul>
901** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
902** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
903** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
904** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
905** </ul>
906**
907** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
908** was given no the corresponding lock.
909**
910** The xShmLock method can transition between unlocked and SHARED or
911** between unlocked and EXCLUSIVE. It cannot transition between SHARED
912** and EXCLUSIVE.
drhf2424c52010-04-26 00:04:55 +0000913*/
drh73b64e42010-05-30 19:55:15 +0000914#define SQLITE_SHM_UNLOCK 1
915#define SQLITE_SHM_LOCK 2
916#define SQLITE_SHM_SHARED 4
917#define SQLITE_SHM_EXCLUSIVE 8
918
919/*
920** CAPI3REF: Maximum xShmLock index
921**
922** The xShmLock method on [sqlite3_io_methods] may use values
923** between 0 and this upper bound as its "offset" argument.
924** The SQLite core will never attempt to acquire or release a
925** lock outside of this range
926*/
927#define SQLITE_SHM_NLOCK 8
928
drhf2424c52010-04-26 00:04:55 +0000929
930/*
drhd68eee02009-12-11 03:44:18 +0000931** CAPI3REF: Initialize The SQLite Library
drh673299b2008-06-09 21:57:22 +0000932**
drhd68eee02009-12-11 03:44:18 +0000933** ^The sqlite3_initialize() routine initializes the
934** SQLite library. ^The sqlite3_shutdown() routine
drhcb041342008-06-12 00:07:29 +0000935** deallocates any resources that were allocated by sqlite3_initialize().
drh481aa742009-11-05 18:46:02 +0000936** These routines are designed to aid in process initialization and
drh9524f4b2009-10-20 15:27:55 +0000937** shutdown on embedded systems. Workstation applications using
938** SQLite normally do not need to invoke either of these routines.
drh673299b2008-06-09 21:57:22 +0000939**
drhcb041342008-06-12 00:07:29 +0000940** A call to sqlite3_initialize() is an "effective" call if it is
941** the first time sqlite3_initialize() is invoked during the lifetime of
942** the process, or if it is the first time sqlite3_initialize() is invoked
drhd68eee02009-12-11 03:44:18 +0000943** following a call to sqlite3_shutdown(). ^(Only an effective call
drhcb041342008-06-12 00:07:29 +0000944** of sqlite3_initialize() does any initialization. All other calls
drhd68eee02009-12-11 03:44:18 +0000945** are harmless no-ops.)^
drhcb041342008-06-12 00:07:29 +0000946**
drhd1a24402009-04-19 12:23:58 +0000947** A call to sqlite3_shutdown() is an "effective" call if it is the first
drhd68eee02009-12-11 03:44:18 +0000948** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
drhd1a24402009-04-19 12:23:58 +0000949** an effective call to sqlite3_shutdown() does any deinitialization.
drhd68eee02009-12-11 03:44:18 +0000950** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
drhd1a24402009-04-19 12:23:58 +0000951**
drh9524f4b2009-10-20 15:27:55 +0000952** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
953** is not. The sqlite3_shutdown() interface must only be called from a
954** single thread. All open [database connections] must be closed and all
955** other SQLite resources must be deallocated prior to invoking
956** sqlite3_shutdown().
957**
drhd68eee02009-12-11 03:44:18 +0000958** Among other things, ^sqlite3_initialize() will invoke
959** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
drh9524f4b2009-10-20 15:27:55 +0000960** will invoke sqlite3_os_end().
drh673299b2008-06-09 21:57:22 +0000961**
drhd68eee02009-12-11 03:44:18 +0000962** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
963** ^If for some reason, sqlite3_initialize() is unable to initialize
drhce5a5a02008-06-10 17:41:44 +0000964** the library (perhaps it is unable to allocate a needed resource such
drhadfae6c2008-10-10 17:26:35 +0000965** as a mutex) it returns an [error code] other than [SQLITE_OK].
drh673299b2008-06-09 21:57:22 +0000966**
drhd68eee02009-12-11 03:44:18 +0000967** ^The sqlite3_initialize() routine is called internally by many other
drhcb041342008-06-12 00:07:29 +0000968** SQLite interfaces so that an application usually does not need to
drhce5a5a02008-06-10 17:41:44 +0000969** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
970** calls sqlite3_initialize() so the SQLite library will be automatically
971** initialized when [sqlite3_open()] is called if it has not be initialized
drhd68eee02009-12-11 03:44:18 +0000972** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
drhcb041342008-06-12 00:07:29 +0000973** compile-time option, then the automatic calls to sqlite3_initialize()
974** are omitted and the application must call sqlite3_initialize() directly
975** prior to using any other SQLite interface. For maximum portability,
976** it is recommended that applications always invoke sqlite3_initialize()
977** directly prior to using any other SQLite interface. Future releases
978** of SQLite may require this. In other words, the behavior exhibited
drhadfae6c2008-10-10 17:26:35 +0000979** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
drhcb041342008-06-12 00:07:29 +0000980** default behavior in some future release of SQLite.
drh673299b2008-06-09 21:57:22 +0000981**
drhcb041342008-06-12 00:07:29 +0000982** The sqlite3_os_init() routine does operating-system specific
983** initialization of the SQLite library. The sqlite3_os_end()
984** routine undoes the effect of sqlite3_os_init(). Typical tasks
985** performed by these routines include allocation or deallocation
986** of static resources, initialization of global variables,
987** setting up a default [sqlite3_vfs] module, or setting up
mihailima3f64902008-06-21 13:35:56 +0000988** a default configuration using [sqlite3_config()].
drh673299b2008-06-09 21:57:22 +0000989**
drhcb041342008-06-12 00:07:29 +0000990** The application should never invoke either sqlite3_os_init()
991** or sqlite3_os_end() directly. The application should only invoke
992** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
mihailima3f64902008-06-21 13:35:56 +0000993** interface is called automatically by sqlite3_initialize() and
drhcb041342008-06-12 00:07:29 +0000994** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
995** implementations for sqlite3_os_init() and sqlite3_os_end()
shane7c7c3112009-08-17 15:31:23 +0000996** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
drh6aa5f152009-08-19 15:57:07 +0000997** When [custom builds | built for other platforms]
998** (using the [SQLITE_OS_OTHER=1] compile-time
drhcb041342008-06-12 00:07:29 +0000999** option) the application must supply a suitable implementation for
1000** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
1001** implementation of sqlite3_os_init() or sqlite3_os_end()
drhadfae6c2008-10-10 17:26:35 +00001002** must return [SQLITE_OK] on success and some other [error code] upon
drhcb041342008-06-12 00:07:29 +00001003** failure.
drh673299b2008-06-09 21:57:22 +00001004*/
drhce5a5a02008-06-10 17:41:44 +00001005int sqlite3_initialize(void);
drh673299b2008-06-09 21:57:22 +00001006int sqlite3_shutdown(void);
drhcb041342008-06-12 00:07:29 +00001007int sqlite3_os_init(void);
1008int sqlite3_os_end(void);
drh673299b2008-06-09 21:57:22 +00001009
drhce5a5a02008-06-10 17:41:44 +00001010/*
drhd68eee02009-12-11 03:44:18 +00001011** CAPI3REF: Configuring The SQLite Library
drhce5a5a02008-06-10 17:41:44 +00001012**
1013** The sqlite3_config() interface is used to make global configuration
1014** changes to SQLite in order to tune SQLite to the specific needs of
1015** the application. The default configuration is recommended for most
1016** applications and so this routine is usually not necessary. It is
1017** provided to support rare applications with unusual needs.
1018**
1019** The sqlite3_config() interface is not threadsafe. The application
1020** must insure that no other SQLite interfaces are invoked by other
1021** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
1022** may only be invoked prior to library initialization using
1023** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
drhd68eee02009-12-11 03:44:18 +00001024** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
1025** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
1026** Note, however, that ^sqlite3_config() can be called as part of the
drh40257ff2008-06-13 18:24:27 +00001027** implementation of an application-defined [sqlite3_os_init()].
drhce5a5a02008-06-10 17:41:44 +00001028**
1029** The first argument to sqlite3_config() is an integer
1030** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
1031** what property of SQLite is to be configured. Subsequent arguments
1032** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
1033** in the first argument.
1034**
drhd68eee02009-12-11 03:44:18 +00001035** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
1036** ^If the option is unknown or SQLite is unable to set the option
drh40257ff2008-06-13 18:24:27 +00001037** then this routine returns a non-zero [error code].
drhce5a5a02008-06-10 17:41:44 +00001038*/
drh9f8da322010-03-10 20:06:37 +00001039int sqlite3_config(int, ...);
drhce5a5a02008-06-10 17:41:44 +00001040
1041/*
drhd68eee02009-12-11 03:44:18 +00001042** CAPI3REF: Configure database connections
drh633e6d52008-07-28 19:34:53 +00001043**
1044** The sqlite3_db_config() interface is used to make configuration
drh2462e322008-07-31 14:47:54 +00001045** changes to a [database connection]. The interface is similar to
1046** [sqlite3_config()] except that the changes apply to a single
1047** [database connection] (specified in the first argument). The
drhd68eee02009-12-11 03:44:18 +00001048** sqlite3_db_config() interface should only be used immediately after
drh2462e322008-07-31 14:47:54 +00001049** the database connection is created using [sqlite3_open()],
1050** [sqlite3_open16()], or [sqlite3_open_v2()].
1051**
1052** The second argument to sqlite3_db_config(D,V,...) is the
1053** configuration verb - an integer code that indicates what
1054** aspect of the [database connection] is being configured.
drhe9d1c722008-08-04 20:13:26 +00001055** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
drh2462e322008-07-31 14:47:54 +00001056** New verbs are likely to be added in future releases of SQLite.
drhe9d1c722008-08-04 20:13:26 +00001057** Additional arguments depend on the verb.
drhf8cecda2008-10-10 23:48:25 +00001058**
drhd68eee02009-12-11 03:44:18 +00001059** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
1060** the call is considered successful.
drh633e6d52008-07-28 19:34:53 +00001061*/
drh9f8da322010-03-10 20:06:37 +00001062int sqlite3_db_config(sqlite3*, int op, ...);
drh633e6d52008-07-28 19:34:53 +00001063
1064/*
drhfb434032009-12-11 23:11:26 +00001065** CAPI3REF: Memory Allocation Routines
drhfec00ea2008-06-14 16:56:21 +00001066**
1067** An instance of this object defines the interface between SQLite
mihailima3f64902008-06-21 13:35:56 +00001068** and low-level memory allocation routines.
drhfec00ea2008-06-14 16:56:21 +00001069**
1070** This object is used in only one place in the SQLite interface.
1071** A pointer to an instance of this object is the argument to
drh4766b292008-06-26 02:53:02 +00001072** [sqlite3_config()] when the configuration option is
drh6aa5f152009-08-19 15:57:07 +00001073** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1074** By creating an instance of this object
1075** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
1076** during configuration, an application can specify an alternative
1077** memory allocation subsystem for SQLite to use for all of its
1078** dynamic memory needs.
drhfec00ea2008-06-14 16:56:21 +00001079**
drh6aa5f152009-08-19 15:57:07 +00001080** Note that SQLite comes with several [built-in memory allocators]
1081** that are perfectly adequate for the overwhelming majority of applications
drhfec00ea2008-06-14 16:56:21 +00001082** and that this object is only useful to a tiny minority of applications
1083** with specialized memory allocation requirements. This object is
1084** also used during testing of SQLite in order to specify an alternative
1085** memory allocator that simulates memory out-of-memory conditions in
1086** order to verify that SQLite recovers gracefully from such
1087** conditions.
1088**
drh6aa5f152009-08-19 15:57:07 +00001089** The xMalloc and xFree methods must work like the
1090** malloc() and free() functions from the standard C library.
1091** The xRealloc method must work like realloc() from the standard C library
1092** with the exception that if the second argument to xRealloc is zero,
1093** xRealloc must be a no-op - it must not perform any allocation or
drhd68eee02009-12-11 03:44:18 +00001094** deallocation. ^SQLite guarantees that the second argument to
drh6aa5f152009-08-19 15:57:07 +00001095** xRealloc is always a value returned by a prior call to xRoundup.
1096** And so in cases where xRoundup always returns a positive number,
1097** xRealloc can perform exactly as the standard library realloc() and
1098** still be in compliance with this specification.
drhfec00ea2008-06-14 16:56:21 +00001099**
1100** xSize should return the allocated size of a memory allocation
1101** previously obtained from xMalloc or xRealloc. The allocated size
1102** is always at least as big as the requested size but may be larger.
1103**
1104** The xRoundup method returns what would be the allocated size of
1105** a memory allocation given a particular requested size. Most memory
1106** allocators round up memory allocations at least to the next multiple
mihailima3f64902008-06-21 13:35:56 +00001107** of 8. Some allocators round up to a larger multiple or to a power of 2.
drh6aa5f152009-08-19 15:57:07 +00001108** Every memory allocation request coming in through [sqlite3_malloc()]
1109** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
1110** that causes the corresponding memory allocation to fail.
drhe5ae5732008-06-15 02:51:47 +00001111**
drhfec00ea2008-06-14 16:56:21 +00001112** The xInit method initializes the memory allocator. (For example,
1113** it might allocate any require mutexes or initialize internal data
1114** structures. The xShutdown method is invoked (indirectly) by
1115** [sqlite3_shutdown()] and should deallocate any resources acquired
1116** by xInit. The pAppData pointer is used as the only parameter to
1117** xInit and xShutdown.
drh9ac06502009-08-17 13:42:29 +00001118**
1119** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
1120** the xInit method, so the xInit method need not be threadsafe. The
1121** xShutdown method is only called from [sqlite3_shutdown()] so it does
drh6aa5f152009-08-19 15:57:07 +00001122** not need to be threadsafe either. For all other methods, SQLite
1123** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
1124** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
1125** it is by default) and so the methods are automatically serialized.
1126** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
1127** methods must be threadsafe or else make their own arrangements for
1128** serialization.
drh9ac06502009-08-17 13:42:29 +00001129**
1130** SQLite will never invoke xInit() more than once without an intervening
1131** call to xShutdown().
drhfec00ea2008-06-14 16:56:21 +00001132*/
1133typedef struct sqlite3_mem_methods sqlite3_mem_methods;
1134struct sqlite3_mem_methods {
1135 void *(*xMalloc)(int); /* Memory allocation function */
1136 void (*xFree)(void*); /* Free a prior allocation */
1137 void *(*xRealloc)(void*,int); /* Resize an allocation */
1138 int (*xSize)(void*); /* Return the size of an allocation */
1139 int (*xRoundup)(int); /* Round up request size to allocation size */
1140 int (*xInit)(void*); /* Initialize the memory allocator */
1141 void (*xShutdown)(void*); /* Deinitialize the memory allocator */
1142 void *pAppData; /* Argument to xInit() and xShutdown() */
1143};
1144
1145/*
drhfb434032009-12-11 23:11:26 +00001146** CAPI3REF: Configuration Options
drhce5a5a02008-06-10 17:41:44 +00001147**
1148** These constants are the available integer configuration options that
1149** can be passed as the first argument to the [sqlite3_config()] interface.
mihailima3f64902008-06-21 13:35:56 +00001150**
drha911abe2008-07-16 13:29:51 +00001151** New configuration options may be added in future releases of SQLite.
1152** Existing configuration options might be discontinued. Applications
1153** should check the return code from [sqlite3_config()] to make sure that
1154** the call worked. The [sqlite3_config()] interface will return a
1155** non-zero [error code] if a discontinued or unsupported configuration option
1156** is invoked.
1157**
drhce5a5a02008-06-10 17:41:44 +00001158** <dl>
1159** <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
drhd68eee02009-12-11 03:44:18 +00001160** <dd>There are no arguments to this option. ^This option sets the
1161** [threading mode] to Single-thread. In other words, it disables
drhce5a5a02008-06-10 17:41:44 +00001162** all mutexing and puts SQLite into a mode where it can only be used
drhd68eee02009-12-11 03:44:18 +00001163** by a single thread. ^If SQLite is compiled with
1164** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1165** it is not possible to change the [threading mode] from its default
1166** value of Single-thread and so [sqlite3_config()] will return
1167** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
1168** configuration option.</dd>
drhce5a5a02008-06-10 17:41:44 +00001169**
1170** <dt>SQLITE_CONFIG_MULTITHREAD</dt>
drhd68eee02009-12-11 03:44:18 +00001171** <dd>There are no arguments to this option. ^This option sets the
1172** [threading mode] to Multi-thread. In other words, it disables
drhce5a5a02008-06-10 17:41:44 +00001173** mutexing on [database connection] and [prepared statement] objects.
1174** The application is responsible for serializing access to
1175** [database connections] and [prepared statements]. But other mutexes
1176** are enabled so that SQLite will be safe to use in a multi-threaded
drhafacce02008-09-02 21:35:03 +00001177** environment as long as no two threads attempt to use the same
drhd68eee02009-12-11 03:44:18 +00001178** [database connection] at the same time. ^If SQLite is compiled with
1179** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1180** it is not possible to set the Multi-thread [threading mode] and
1181** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1182** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
drhce5a5a02008-06-10 17:41:44 +00001183**
1184** <dt>SQLITE_CONFIG_SERIALIZED</dt>
drhd68eee02009-12-11 03:44:18 +00001185** <dd>There are no arguments to this option. ^This option sets the
1186** [threading mode] to Serialized. In other words, this option enables
drhce5a5a02008-06-10 17:41:44 +00001187** all mutexes including the recursive
1188** mutexes on [database connection] and [prepared statement] objects.
1189** In this mode (which is the default when SQLite is compiled with
drh4766b292008-06-26 02:53:02 +00001190** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
drhce5a5a02008-06-10 17:41:44 +00001191** to [database connections] and [prepared statements] so that the
1192** application is free to use the same [database connection] or the
drh31d38cf2008-07-12 20:35:08 +00001193** same [prepared statement] in different threads at the same time.
drhd68eee02009-12-11 03:44:18 +00001194** ^If SQLite is compiled with
1195** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1196** it is not possible to set the Serialized [threading mode] and
1197** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
1198** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
drhce5a5a02008-06-10 17:41:44 +00001199**
1200** <dt>SQLITE_CONFIG_MALLOC</dt>
drhd68eee02009-12-11 03:44:18 +00001201** <dd> ^(This option takes a single argument which is a pointer to an
mihailimdb4f2ad2008-06-21 11:20:48 +00001202** instance of the [sqlite3_mem_methods] structure. The argument specifies
1203** alternative low-level memory allocation routines to be used in place of
drhd68eee02009-12-11 03:44:18 +00001204** the memory allocation routines built into SQLite.)^ ^SQLite makes
1205** its own private copy of the content of the [sqlite3_mem_methods] structure
1206** before the [sqlite3_config()] call returns.</dd>
drhce5a5a02008-06-10 17:41:44 +00001207**
drh33589792008-06-18 13:27:46 +00001208** <dt>SQLITE_CONFIG_GETMALLOC</dt>
drhd68eee02009-12-11 03:44:18 +00001209** <dd> ^(This option takes a single argument which is a pointer to an
drh33589792008-06-18 13:27:46 +00001210** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
drhd68eee02009-12-11 03:44:18 +00001211** structure is filled with the currently defined memory allocation routines.)^
drh33589792008-06-18 13:27:46 +00001212** This option can be used to overload the default memory allocation
1213** routines with a wrapper that simulations memory allocation failure or
drhd68eee02009-12-11 03:44:18 +00001214** tracks memory usage, for example. </dd>
drh33589792008-06-18 13:27:46 +00001215**
drhfec00ea2008-06-14 16:56:21 +00001216** <dt>SQLITE_CONFIG_MEMSTATUS</dt>
drhd68eee02009-12-11 03:44:18 +00001217** <dd> ^This option takes single argument of type int, interpreted as a
danielk197795c232d2008-07-28 05:22:35 +00001218** boolean, which enables or disables the collection of memory allocation
drhd68eee02009-12-11 03:44:18 +00001219** statistics. ^(When memory allocation statistics are disabled, the
1220** following SQLite interfaces become non-operational:
drhce5a5a02008-06-10 17:41:44 +00001221** <ul>
1222** <li> [sqlite3_memory_used()]
1223** <li> [sqlite3_memory_highwater()]
1224** <li> [sqlite3_soft_heap_limit()]
drh0a60a382008-07-31 17:16:05 +00001225** <li> [sqlite3_status()]
drhd68eee02009-12-11 03:44:18 +00001226** </ul>)^
1227** ^Memory allocation statistics are enabled by default unless SQLite is
1228** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
1229** allocation statistics are disabled by default.
drhce5a5a02008-06-10 17:41:44 +00001230** </dd>
drh33589792008-06-18 13:27:46 +00001231**
1232** <dt>SQLITE_CONFIG_SCRATCH</dt>
drhd68eee02009-12-11 03:44:18 +00001233** <dd> ^This option specifies a static memory buffer that SQLite can use for
drh6860da02009-06-09 19:53:58 +00001234** scratch memory. There are three arguments: A pointer an 8-byte
1235** aligned memory buffer from which the scrach allocations will be
1236** drawn, the size of each scratch allocation (sz),
1237** and the maximum number of scratch allocations (N). The sz
drh0a60a382008-07-31 17:16:05 +00001238** argument must be a multiple of 16. The sz parameter should be a few bytes
drh6860da02009-06-09 19:53:58 +00001239** larger than the actual scratch space required due to internal overhead.
drhd68eee02009-12-11 03:44:18 +00001240** The first argument must be a pointer to an 8-byte aligned buffer
drh6860da02009-06-09 19:53:58 +00001241** of at least sz*N bytes of memory.
drhd68eee02009-12-11 03:44:18 +00001242** ^SQLite will use no more than one scratch buffer per thread. So
1243** N should be set to the expected maximum number of threads. ^SQLite will
1244** never require a scratch buffer that is more than 6 times the database
1245** page size. ^If SQLite needs needs additional scratch memory beyond
1246** what is provided by this configuration option, then
1247** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
drh33589792008-06-18 13:27:46 +00001248**
1249** <dt>SQLITE_CONFIG_PAGECACHE</dt>
drhd68eee02009-12-11 03:44:18 +00001250** <dd> ^This option specifies a static memory buffer that SQLite can use for
drh21614742008-11-18 19:18:08 +00001251** the database page cache with the default page cache implemenation.
1252** This configuration should not be used if an application-define page
1253** cache implementation is loaded using the SQLITE_CONFIG_PCACHE option.
drh6860da02009-06-09 19:53:58 +00001254** There are three arguments to this option: A pointer to 8-byte aligned
mihailimdb4f2ad2008-06-21 11:20:48 +00001255** memory, the size of each page buffer (sz), and the number of pages (N).
drh6860da02009-06-09 19:53:58 +00001256** The sz argument should be the size of the largest database page
1257** (a power of two between 512 and 32768) plus a little extra for each
drhd68eee02009-12-11 03:44:18 +00001258** page header. ^The page header size is 20 to 40 bytes depending on
1259** the host architecture. ^It is harmless, apart from the wasted memory,
drh6860da02009-06-09 19:53:58 +00001260** to make sz a little too large. The first
drh0a60a382008-07-31 17:16:05 +00001261** argument should point to an allocation of at least sz*N bytes of memory.
drhd68eee02009-12-11 03:44:18 +00001262** ^SQLite will use the memory provided by the first argument to satisfy its
1263** memory needs for the first N pages that it adds to cache. ^If additional
mihailimdb4f2ad2008-06-21 11:20:48 +00001264** page cache memory is needed beyond what is provided by this option, then
drh0a60a382008-07-31 17:16:05 +00001265** SQLite goes to [sqlite3_malloc()] for the additional storage space.
drhd68eee02009-12-11 03:44:18 +00001266** ^The implementation might use one or more of the N buffers to hold
drh6860da02009-06-09 19:53:58 +00001267** memory accounting information. The pointer in the first argument must
1268** be aligned to an 8-byte boundary or subsequent behavior of SQLite
1269** will be undefined.</dd>
drh33589792008-06-18 13:27:46 +00001270**
1271** <dt>SQLITE_CONFIG_HEAP</dt>
drhd68eee02009-12-11 03:44:18 +00001272** <dd> ^This option specifies a static memory buffer that SQLite will use
drh33589792008-06-18 13:27:46 +00001273** for all of its dynamic memory allocation needs beyond those provided
1274** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
drh6860da02009-06-09 19:53:58 +00001275** There are three arguments: An 8-byte aligned pointer to the memory,
1276** the number of bytes in the memory buffer, and the minimum allocation size.
drhd68eee02009-12-11 03:44:18 +00001277** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
drh8a42cbd2008-07-10 18:13:42 +00001278** to using its default memory allocator (the system malloc() implementation),
drhd68eee02009-12-11 03:44:18 +00001279** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
drh8a42cbd2008-07-10 18:13:42 +00001280** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
1281** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
drh39bf74a2009-06-09 18:02:10 +00001282** allocator is engaged to handle all of SQLites memory allocation needs.
1283** The first pointer (the memory pointer) must be aligned to an 8-byte
drh6860da02009-06-09 19:53:58 +00001284** boundary or subsequent behavior of SQLite will be undefined.</dd>
drh33589792008-06-18 13:27:46 +00001285**
1286** <dt>SQLITE_CONFIG_MUTEX</dt>
drhd68eee02009-12-11 03:44:18 +00001287** <dd> ^(This option takes a single argument which is a pointer to an
mihailimdb4f2ad2008-06-21 11:20:48 +00001288** instance of the [sqlite3_mutex_methods] structure. The argument specifies
drh33589792008-06-18 13:27:46 +00001289** alternative low-level mutex routines to be used in place
drhd68eee02009-12-11 03:44:18 +00001290** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
1291** content of the [sqlite3_mutex_methods] structure before the call to
1292** [sqlite3_config()] returns. ^If SQLite is compiled with
1293** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1294** the entire mutexing subsystem is omitted from the build and hence calls to
1295** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
1296** return [SQLITE_ERROR].</dd>
drh33589792008-06-18 13:27:46 +00001297**
drh584ff182008-07-14 18:38:17 +00001298** <dt>SQLITE_CONFIG_GETMUTEX</dt>
drhd68eee02009-12-11 03:44:18 +00001299** <dd> ^(This option takes a single argument which is a pointer to an
drh33589792008-06-18 13:27:46 +00001300** instance of the [sqlite3_mutex_methods] structure. The
1301** [sqlite3_mutex_methods]
drhd68eee02009-12-11 03:44:18 +00001302** structure is filled with the currently defined mutex routines.)^
drh33589792008-06-18 13:27:46 +00001303** This option can be used to overload the default mutex allocation
1304** routines with a wrapper used to track mutex usage for performance
drhd68eee02009-12-11 03:44:18 +00001305** profiling or testing, for example. ^If SQLite is compiled with
1306** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
1307** the entire mutexing subsystem is omitted from the build and hence calls to
1308** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
1309** return [SQLITE_ERROR].</dd>
drh633e6d52008-07-28 19:34:53 +00001310**
1311** <dt>SQLITE_CONFIG_LOOKASIDE</dt>
drhd68eee02009-12-11 03:44:18 +00001312** <dd> ^(This option takes two arguments that determine the default
drh9be37f62009-12-12 23:57:36 +00001313** memory allocation for the lookaside memory allocator on each
1314** [database connection]. The first argument is the
drh633e6d52008-07-28 19:34:53 +00001315** size of each lookaside buffer slot and the second is the number of
drhd68eee02009-12-11 03:44:18 +00001316** slots allocated to each database connection.)^ ^(This option sets the
1317** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
drh6aa5f152009-08-19 15:57:07 +00001318** verb to [sqlite3_db_config()] can be used to change the lookaside
drhd68eee02009-12-11 03:44:18 +00001319** configuration on individual connections.)^ </dd>
drh633e6d52008-07-28 19:34:53 +00001320**
drh21614742008-11-18 19:18:08 +00001321** <dt>SQLITE_CONFIG_PCACHE</dt>
drhd68eee02009-12-11 03:44:18 +00001322** <dd> ^(This option takes a single argument which is a pointer to
drh21614742008-11-18 19:18:08 +00001323** an [sqlite3_pcache_methods] object. This object specifies the interface
drhd68eee02009-12-11 03:44:18 +00001324** to a custom page cache implementation.)^ ^SQLite makes a copy of the
drh21614742008-11-18 19:18:08 +00001325** object and uses it for page cache memory allocations.</dd>
1326**
1327** <dt>SQLITE_CONFIG_GETPCACHE</dt>
drhd68eee02009-12-11 03:44:18 +00001328** <dd> ^(This option takes a single argument which is a pointer to an
drh21614742008-11-18 19:18:08 +00001329** [sqlite3_pcache_methods] object. SQLite copies of the current
drhd68eee02009-12-11 03:44:18 +00001330** page cache implementation into that object.)^ </dd>
drh21614742008-11-18 19:18:08 +00001331**
drhd3d986d2010-03-31 13:57:56 +00001332** <dt>SQLITE_CONFIG_LOG</dt>
1333** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1334** function with a call signature of void(*)(void*,int,const char*),
1335** and a pointer to void. ^If the function pointer is not NULL, it is
1336** invoked by [sqlite3_log()] to process each logging event. ^If the
1337** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
1338** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
1339** passed through as the first parameter to the application-defined logger
1340** function whenever that function is invoked. ^The second parameter to
1341** the logger function is a copy of the first parameter to the corresponding
1342** [sqlite3_log()] call and is intended to be a [result code] or an
1343** [extended result code]. ^The third parameter passed to the logger is
1344** log message after formatting via [sqlite3_snprintf()].
1345** The SQLite logging interface is not reentrant; the logger function
1346** supplied by the application must not invoke any SQLite interface.
1347** In a multi-threaded application, the application-defined logger
1348** function must be threadsafe. </dd>
1349**
drh633e6d52008-07-28 19:34:53 +00001350** </dl>
mihailima3f64902008-06-21 13:35:56 +00001351*/
drh40257ff2008-06-13 18:24:27 +00001352#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
1353#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
1354#define SQLITE_CONFIG_SERIALIZED 3 /* nil */
drhfec00ea2008-06-14 16:56:21 +00001355#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
drh33589792008-06-18 13:27:46 +00001356#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
1357#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
1358#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
1359#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
1360#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
1361#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
1362#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
shane2479de32008-11-10 18:05:35 +00001363/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
drh633e6d52008-07-28 19:34:53 +00001364#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
danielk1977bc2ca9e2008-11-13 14:28:28 +00001365#define SQLITE_CONFIG_PCACHE 14 /* sqlite3_pcache_methods* */
1366#define SQLITE_CONFIG_GETPCACHE 15 /* sqlite3_pcache_methods* */
drh3f280702010-02-18 18:45:09 +00001367#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
danielk19772d340812008-07-24 08:20:40 +00001368
drhe9d1c722008-08-04 20:13:26 +00001369/*
drh9f8da322010-03-10 20:06:37 +00001370** CAPI3REF: Database Connection Configuration Options
drhe9d1c722008-08-04 20:13:26 +00001371**
1372** These constants are the available integer configuration options that
1373** can be passed as the second argument to the [sqlite3_db_config()] interface.
1374**
1375** New configuration options may be added in future releases of SQLite.
1376** Existing configuration options might be discontinued. Applications
1377** should check the return code from [sqlite3_db_config()] to make sure that
drhd68eee02009-12-11 03:44:18 +00001378** the call worked. ^The [sqlite3_db_config()] interface will return a
drhe9d1c722008-08-04 20:13:26 +00001379** non-zero [error code] if a discontinued or unsupported configuration option
1380** is invoked.
1381**
1382** <dl>
1383** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
drhd68eee02009-12-11 03:44:18 +00001384** <dd> ^This option takes three additional arguments that determine the
drhe9d1c722008-08-04 20:13:26 +00001385** [lookaside memory allocator] configuration for the [database connection].
drhd68eee02009-12-11 03:44:18 +00001386** ^The first argument (the third parameter to [sqlite3_db_config()] is a
drh6aa5f152009-08-19 15:57:07 +00001387** pointer to an memory buffer to use for lookaside memory.
drhd68eee02009-12-11 03:44:18 +00001388** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
1389** may be NULL in which case SQLite will allocate the
1390** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
1391** size of each lookaside buffer slot. ^The third argument is the number of
drhe9d1c722008-08-04 20:13:26 +00001392** slots. The size of the buffer in the first argument must be greater than
drh6aa5f152009-08-19 15:57:07 +00001393** or equal to the product of the second and third arguments. The buffer
drhd68eee02009-12-11 03:44:18 +00001394** must be aligned to an 8-byte boundary. ^If the second argument to
1395** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
1396** rounded down to the next smaller
drh6aa5f152009-08-19 15:57:07 +00001397** multiple of 8. See also: [SQLITE_CONFIG_LOOKASIDE]</dd>
drhe9d1c722008-08-04 20:13:26 +00001398**
1399** </dl>
1400*/
1401#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
1402
drhce5a5a02008-06-10 17:41:44 +00001403
drh673299b2008-06-09 21:57:22 +00001404/*
drhd68eee02009-12-11 03:44:18 +00001405** CAPI3REF: Enable Or Disable Extended Result Codes
drh6ed48bf2007-06-14 20:57:18 +00001406**
drhd68eee02009-12-11 03:44:18 +00001407** ^The sqlite3_extended_result_codes() routine enables or disables the
1408** [extended result codes] feature of SQLite. ^The extended result
1409** codes are disabled by default for historical compatibility.
drh4ac285a2006-09-15 07:28:50 +00001410*/
1411int sqlite3_extended_result_codes(sqlite3*, int onoff);
1412
1413/*
drhd68eee02009-12-11 03:44:18 +00001414** CAPI3REF: Last Insert Rowid
drh6ed48bf2007-06-14 20:57:18 +00001415**
drhd68eee02009-12-11 03:44:18 +00001416** ^Each entry in an SQLite table has a unique 64-bit signed
1417** integer key called the [ROWID | "rowid"]. ^The rowid is always available
drhfddfa2d2007-12-05 18:05:16 +00001418** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
drhd68eee02009-12-11 03:44:18 +00001419** names are not also used by explicitly declared columns. ^If
drh49c3d572008-12-15 22:51:38 +00001420** the table has a column of type [INTEGER PRIMARY KEY] then that column
mlcreechb2799412008-03-07 03:20:31 +00001421** is another alias for the rowid.
drh6ed48bf2007-06-14 20:57:18 +00001422**
drhd68eee02009-12-11 03:44:18 +00001423** ^This routine returns the [rowid] of the most recent
drhf8cecda2008-10-10 23:48:25 +00001424** successful [INSERT] into the database from the [database connection]
drhd68eee02009-12-11 03:44:18 +00001425** in the first argument. ^If no successful [INSERT]s
mihailimdb4f2ad2008-06-21 11:20:48 +00001426** have ever occurred on that database connection, zero is returned.
drh6ed48bf2007-06-14 20:57:18 +00001427**
drhd68eee02009-12-11 03:44:18 +00001428** ^(If an [INSERT] occurs within a trigger, then the [rowid] of the inserted
mihailimdb4f2ad2008-06-21 11:20:48 +00001429** row is returned by this routine as long as the trigger is running.
1430** But once the trigger terminates, the value returned by this routine
drhd68eee02009-12-11 03:44:18 +00001431** reverts to the last value inserted before the trigger fired.)^
drhe30f4422007-08-21 16:15:55 +00001432**
drhd68eee02009-12-11 03:44:18 +00001433** ^An [INSERT] that fails due to a constraint violation is not a
drhf8cecda2008-10-10 23:48:25 +00001434** successful [INSERT] and does not change the value returned by this
drhd68eee02009-12-11 03:44:18 +00001435** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
drhdc1d9f12007-10-27 16:25:16 +00001436** and INSERT OR ABORT make no changes to the return value of this
drhd68eee02009-12-11 03:44:18 +00001437** routine when their insertion fails. ^(When INSERT OR REPLACE
drhdc1d9f12007-10-27 16:25:16 +00001438** encounters a constraint violation, it does not fail. The
1439** INSERT continues to completion after deleting rows that caused
1440** the constraint problem so INSERT OR REPLACE will always change
drhd68eee02009-12-11 03:44:18 +00001441** the return value of this interface.)^
drhdc1d9f12007-10-27 16:25:16 +00001442**
drhd68eee02009-12-11 03:44:18 +00001443** ^For the purposes of this routine, an [INSERT] is considered to
drh33c1be32008-01-30 16:16:14 +00001444** be successful even if it is subsequently rolled back.
1445**
drha94cc422009-12-03 01:01:02 +00001446** This function is accessible to SQL statements via the
1447** [last_insert_rowid() SQL function].
1448**
drh8b39db12009-02-18 18:37:58 +00001449** If a separate thread performs a new [INSERT] on the same
1450** database connection while the [sqlite3_last_insert_rowid()]
1451** function is running and thus changes the last insert [rowid],
1452** then the value returned by [sqlite3_last_insert_rowid()] is
1453** unpredictable and might not equal either the old or the new
1454** last insert [rowid].
drhaf9ff332002-01-16 21:00:27 +00001455*/
drh6d2069d2007-08-14 01:58:53 +00001456sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
drhaf9ff332002-01-16 21:00:27 +00001457
drhc8d30ac2002-04-12 10:08:59 +00001458/*
drhd68eee02009-12-11 03:44:18 +00001459** CAPI3REF: Count The Number Of Rows Modified
drh6ed48bf2007-06-14 20:57:18 +00001460**
drhd68eee02009-12-11 03:44:18 +00001461** ^This function returns the number of database rows that were changed
drhfddfa2d2007-12-05 18:05:16 +00001462** or inserted or deleted by the most recently completed SQL statement
mihailimdb4f2ad2008-06-21 11:20:48 +00001463** on the [database connection] specified by the first parameter.
drhd68eee02009-12-11 03:44:18 +00001464** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
drhf8cecda2008-10-10 23:48:25 +00001465** or [DELETE] statement are counted. Auxiliary changes caused by
drhd68eee02009-12-11 03:44:18 +00001466** triggers or [foreign key actions] are not counted.)^ Use the
danb6163092009-10-07 10:43:26 +00001467** [sqlite3_total_changes()] function to find the total number of changes
1468** including changes caused by triggers and foreign key actions.
drh6ed48bf2007-06-14 20:57:18 +00001469**
drhd68eee02009-12-11 03:44:18 +00001470** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
drhd9c20d72009-04-29 14:33:44 +00001471** are not counted. Only real table changes are counted.
1472**
drhd68eee02009-12-11 03:44:18 +00001473** ^(A "row change" is a change to a single row of a single table
drh33c1be32008-01-30 16:16:14 +00001474** caused by an INSERT, DELETE, or UPDATE statement. Rows that
drhd9c20d72009-04-29 14:33:44 +00001475** are changed as side effects of [REPLACE] constraint resolution,
1476** rollback, ABORT processing, [DROP TABLE], or by any other
drhd68eee02009-12-11 03:44:18 +00001477** mechanisms do not count as direct row changes.)^
drh33c1be32008-01-30 16:16:14 +00001478**
1479** A "trigger context" is a scope of execution that begins and
drhd9c20d72009-04-29 14:33:44 +00001480** ends with the script of a [CREATE TRIGGER | trigger].
1481** Most SQL statements are
drh33c1be32008-01-30 16:16:14 +00001482** evaluated outside of any trigger. This is the "top level"
1483** trigger context. If a trigger fires from the top level, a
1484** new trigger context is entered for the duration of that one
1485** trigger. Subtriggers create subcontexts for their duration.
1486**
drhd68eee02009-12-11 03:44:18 +00001487** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
drh33c1be32008-01-30 16:16:14 +00001488** not create a new trigger context.
1489**
drhd68eee02009-12-11 03:44:18 +00001490** ^This function returns the number of direct row changes in the
drh33c1be32008-01-30 16:16:14 +00001491** most recent INSERT, UPDATE, or DELETE statement within the same
1492** trigger context.
1493**
drhd68eee02009-12-11 03:44:18 +00001494** ^Thus, when called from the top level, this function returns the
drh33c1be32008-01-30 16:16:14 +00001495** number of changes in the most recent INSERT, UPDATE, or DELETE
drhd68eee02009-12-11 03:44:18 +00001496** that also occurred at the top level. ^(Within the body of a trigger,
mihailimdb4f2ad2008-06-21 11:20:48 +00001497** the sqlite3_changes() interface can be called to find the number of
drh930cc582007-03-28 13:07:40 +00001498** changes in the most recently completed INSERT, UPDATE, or DELETE
drhf5befa02007-12-06 02:42:07 +00001499** statement within the body of the same trigger.
mihailimdb4f2ad2008-06-21 11:20:48 +00001500** However, the number returned does not include changes
drhd68eee02009-12-11 03:44:18 +00001501** caused by subtriggers since those have their own context.)^
drhc8d30ac2002-04-12 10:08:59 +00001502**
drha94cc422009-12-03 01:01:02 +00001503** See also the [sqlite3_total_changes()] interface, the
1504** [count_changes pragma], and the [changes() SQL function].
drhe30f4422007-08-21 16:15:55 +00001505**
drh8b39db12009-02-18 18:37:58 +00001506** If a separate thread makes changes on the same database connection
1507** while [sqlite3_changes()] is running then the value returned
1508** is unpredictable and not meaningful.
drhc8d30ac2002-04-12 10:08:59 +00001509*/
danielk1977f9d64d22004-06-19 08:18:07 +00001510int sqlite3_changes(sqlite3*);
drhc8d30ac2002-04-12 10:08:59 +00001511
rdcf146a772004-02-25 22:51:06 +00001512/*
drhd68eee02009-12-11 03:44:18 +00001513** CAPI3REF: Total Number Of Rows Modified
mihailimdb4f2ad2008-06-21 11:20:48 +00001514**
drhd68eee02009-12-11 03:44:18 +00001515** ^This function returns the number of row changes caused by [INSERT],
drhd9c20d72009-04-29 14:33:44 +00001516** [UPDATE] or [DELETE] statements since the [database connection] was opened.
drhd68eee02009-12-11 03:44:18 +00001517** ^(The count returned by sqlite3_total_changes() includes all changes
1518** from all [CREATE TRIGGER | trigger] contexts and changes made by
1519** [foreign key actions]. However,
drhd9c20d72009-04-29 14:33:44 +00001520** the count does not include changes used to implement [REPLACE] constraints,
1521** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
drh4fb08662009-05-22 01:02:26 +00001522** count does not include rows of views that fire an [INSTEAD OF trigger],
1523** though if the INSTEAD OF trigger makes changes of its own, those changes
drhd68eee02009-12-11 03:44:18 +00001524** are counted.)^
1525** ^The sqlite3_total_changes() function counts the changes as soon as
1526** the statement that makes them is completed (when the statement handle
1527** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
drh6ed48bf2007-06-14 20:57:18 +00001528**
drha94cc422009-12-03 01:01:02 +00001529** See also the [sqlite3_changes()] interface, the
1530** [count_changes pragma], and the [total_changes() SQL function].
drh33c1be32008-01-30 16:16:14 +00001531**
drh8b39db12009-02-18 18:37:58 +00001532** If a separate thread makes changes on the same database connection
1533** while [sqlite3_total_changes()] is running then the value
1534** returned is unpredictable and not meaningful.
rdcf146a772004-02-25 22:51:06 +00001535*/
danielk1977b28af712004-06-21 06:50:26 +00001536int sqlite3_total_changes(sqlite3*);
1537
drh6ed48bf2007-06-14 20:57:18 +00001538/*
drhd68eee02009-12-11 03:44:18 +00001539** CAPI3REF: Interrupt A Long-Running Query
drh6ed48bf2007-06-14 20:57:18 +00001540**
drhd68eee02009-12-11 03:44:18 +00001541** ^This function causes any pending database operation to abort and
drh33c1be32008-01-30 16:16:14 +00001542** return at its earliest opportunity. This routine is typically
mihailimebe796c2008-06-21 20:11:17 +00001543** called in response to a user action such as pressing "Cancel"
drh4c504392000-10-16 22:06:40 +00001544** or Ctrl-C where the user wants a long query operation to halt
1545** immediately.
drh930cc582007-03-28 13:07:40 +00001546**
drhd68eee02009-12-11 03:44:18 +00001547** ^It is safe to call this routine from a thread different from the
drh33c1be32008-01-30 16:16:14 +00001548** thread that is currently running the database operation. But it
mihailimdb4f2ad2008-06-21 11:20:48 +00001549** is not safe to call this routine with a [database connection] that
drh871f6ca2007-08-14 18:03:14 +00001550** is closed or might close before sqlite3_interrupt() returns.
drh6ed48bf2007-06-14 20:57:18 +00001551**
drhd68eee02009-12-11 03:44:18 +00001552** ^If an SQL operation is very nearly finished at the time when
mihailimdb4f2ad2008-06-21 11:20:48 +00001553** sqlite3_interrupt() is called, then it might not have an opportunity
1554** to be interrupted and might continue to completion.
1555**
drhd68eee02009-12-11 03:44:18 +00001556** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
1557** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
mihailimdb4f2ad2008-06-21 11:20:48 +00001558** that is inside an explicit transaction, then the entire transaction
1559** will be rolled back automatically.
1560**
drhdf6473a2009-12-13 22:20:08 +00001561** ^The sqlite3_interrupt(D) call is in effect until all currently running
1562** SQL statements on [database connection] D complete. ^Any new SQL statements
drhd2b68432009-04-20 12:31:46 +00001563** that are started after the sqlite3_interrupt() call and before the
1564** running statements reaches zero are interrupted as if they had been
drhdf6473a2009-12-13 22:20:08 +00001565** running prior to the sqlite3_interrupt() call. ^New SQL statements
drhd2b68432009-04-20 12:31:46 +00001566** that are started after the running statement count reaches zero are
drhdf6473a2009-12-13 22:20:08 +00001567** not effected by the sqlite3_interrupt().
drhd68eee02009-12-11 03:44:18 +00001568** ^A call to sqlite3_interrupt(D) that occurs when there are no running
drhd2b68432009-04-20 12:31:46 +00001569** SQL statements is a no-op and has no effect on SQL statements
1570** that are started after the sqlite3_interrupt() call returns.
drh33c1be32008-01-30 16:16:14 +00001571**
drh8b39db12009-02-18 18:37:58 +00001572** If the database connection closes while [sqlite3_interrupt()]
1573** is running then bad things will likely happen.
drh4c504392000-10-16 22:06:40 +00001574*/
danielk1977f9d64d22004-06-19 08:18:07 +00001575void sqlite3_interrupt(sqlite3*);
drh4c504392000-10-16 22:06:40 +00001576
drh6ed48bf2007-06-14 20:57:18 +00001577/*
drhd68eee02009-12-11 03:44:18 +00001578** CAPI3REF: Determine If An SQL Statement Is Complete
drh75897232000-05-29 14:26:00 +00001579**
drh709915d2009-04-28 04:46:41 +00001580** These routines are useful during command-line input to determine if the
1581** currently entered text seems to form a complete SQL statement or
drhf5befa02007-12-06 02:42:07 +00001582** if additional input is needed before sending the text into
drhd68eee02009-12-11 03:44:18 +00001583** SQLite for parsing. ^These routines return 1 if the input string
1584** appears to be a complete SQL statement. ^A statement is judged to be
drh709915d2009-04-28 04:46:41 +00001585** complete if it ends with a semicolon token and is not a prefix of a
drhd68eee02009-12-11 03:44:18 +00001586** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
drh33c1be32008-01-30 16:16:14 +00001587** string literals or quoted identifier names or comments are not
1588** independent tokens (they are part of the token in which they are
drhd68eee02009-12-11 03:44:18 +00001589** embedded) and thus do not count as a statement terminator. ^Whitespace
drh709915d2009-04-28 04:46:41 +00001590** and comments that follow the final semicolon are ignored.
1591**
drhd68eee02009-12-11 03:44:18 +00001592** ^These routines return 0 if the statement is incomplete. ^If a
drh709915d2009-04-28 04:46:41 +00001593** memory allocation fails, then SQLITE_NOMEM is returned.
drh33c1be32008-01-30 16:16:14 +00001594**
drhd68eee02009-12-11 03:44:18 +00001595** ^These routines do not parse the SQL statements thus
mihailimdb4f2ad2008-06-21 11:20:48 +00001596** will not detect syntactically incorrect SQL.
drhfddfa2d2007-12-05 18:05:16 +00001597**
drhd68eee02009-12-11 03:44:18 +00001598** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
drh709915d2009-04-28 04:46:41 +00001599** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
1600** automatically by sqlite3_complete16(). If that initialization fails,
1601** then the return value from sqlite3_complete16() will be non-zero
drhd68eee02009-12-11 03:44:18 +00001602** regardless of whether or not the input SQL is complete.)^
drh33c1be32008-01-30 16:16:14 +00001603**
drh8b39db12009-02-18 18:37:58 +00001604** The input to [sqlite3_complete()] must be a zero-terminated
1605** UTF-8 string.
drh33c1be32008-01-30 16:16:14 +00001606**
drh8b39db12009-02-18 18:37:58 +00001607** The input to [sqlite3_complete16()] must be a zero-terminated
1608** UTF-16 string in native byte order.
drh75897232000-05-29 14:26:00 +00001609*/
danielk19776f8a5032004-05-10 10:34:51 +00001610int sqlite3_complete(const char *sql);
danielk197761de0d12004-05-27 23:56:16 +00001611int sqlite3_complete16(const void *sql);
drh75897232000-05-29 14:26:00 +00001612
drh2dfbbca2000-07-28 14:32:48 +00001613/*
drhd68eee02009-12-11 03:44:18 +00001614** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
drh6ed48bf2007-06-14 20:57:18 +00001615**
drhd68eee02009-12-11 03:44:18 +00001616** ^This routine sets a callback function that might be invoked whenever
mihailimdb4f2ad2008-06-21 11:20:48 +00001617** an attempt is made to open a database table that another thread
1618** or process has locked.
1619**
drhd68eee02009-12-11 03:44:18 +00001620** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
1621** is returned immediately upon encountering the lock. ^If the busy callback
1622** is not NULL, then the callback might be invoked with two arguments.
mihailimdb4f2ad2008-06-21 11:20:48 +00001623**
drhd68eee02009-12-11 03:44:18 +00001624** ^The first argument to the busy handler is a copy of the void* pointer which
1625** is the third argument to sqlite3_busy_handler(). ^The second argument to
1626** the busy handler callback is the number of times that the busy handler has
1627** been invoked for this locking event. ^If the
drh6ed48bf2007-06-14 20:57:18 +00001628** busy callback returns 0, then no additional attempts are made to
1629** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
drhd68eee02009-12-11 03:44:18 +00001630** ^If the callback returns non-zero, then another attempt
drhfddfa2d2007-12-05 18:05:16 +00001631** is made to open the database for reading and the cycle repeats.
drh2dfbbca2000-07-28 14:32:48 +00001632**
mihailimdb4f2ad2008-06-21 11:20:48 +00001633** The presence of a busy handler does not guarantee that it will be invoked
drhd68eee02009-12-11 03:44:18 +00001634** when there is lock contention. ^If SQLite determines that invoking the busy
mihailimdb4f2ad2008-06-21 11:20:48 +00001635** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1636** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
drh86939b52007-01-10 12:54:51 +00001637** Consider a scenario where one process is holding a read lock that
1638** it is trying to promote to a reserved lock and
1639** a second process is holding a reserved lock that it is trying
1640** to promote to an exclusive lock. The first process cannot proceed
1641** because it is blocked by the second and the second process cannot
1642** proceed because it is blocked by the first. If both processes
drhf5befa02007-12-06 02:42:07 +00001643** invoke the busy handlers, neither will make any progress. Therefore,
drh6ed48bf2007-06-14 20:57:18 +00001644** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
drh86939b52007-01-10 12:54:51 +00001645** will induce the first process to release its read lock and allow
1646** the second process to proceed.
1647**
drhd68eee02009-12-11 03:44:18 +00001648** ^The default busy callback is NULL.
drh2dfbbca2000-07-28 14:32:48 +00001649**
drhd68eee02009-12-11 03:44:18 +00001650** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
drhfddfa2d2007-12-05 18:05:16 +00001651** when SQLite is in the middle of a large transaction where all the
drh33c1be32008-01-30 16:16:14 +00001652** changes will not fit into the in-memory cache. SQLite will
drh6ed48bf2007-06-14 20:57:18 +00001653** already hold a RESERVED lock on the database file, but it needs
1654** to promote this lock to EXCLUSIVE so that it can spill cache
1655** pages into the database file without harm to concurrent
drhd68eee02009-12-11 03:44:18 +00001656** readers. ^If it is unable to promote the lock, then the in-memory
drh6ed48bf2007-06-14 20:57:18 +00001657** cache will be left in an inconsistent state and so the error
1658** code is promoted from the relatively benign [SQLITE_BUSY] to
drhd68eee02009-12-11 03:44:18 +00001659** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion
drh33c1be32008-01-30 16:16:14 +00001660** forces an automatic rollback of the changes. See the
mihailimdb4f2ad2008-06-21 11:20:48 +00001661** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
drh6ed48bf2007-06-14 20:57:18 +00001662** CorruptionFollowingBusyError</a> wiki page for a discussion of why
1663** this is important.
mihailimdb4f2ad2008-06-21 11:20:48 +00001664**
drhd68eee02009-12-11 03:44:18 +00001665** ^(There can only be a single busy handler defined for each
mihailimdb4f2ad2008-06-21 11:20:48 +00001666** [database connection]. Setting a new busy handler clears any
drhd68eee02009-12-11 03:44:18 +00001667** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
mihailimdb4f2ad2008-06-21 11:20:48 +00001668** will also set or clear the busy handler.
drhd677b3d2007-08-20 22:48:41 +00001669**
drhc8075422008-09-10 13:09:23 +00001670** The busy callback should not take any actions which modify the
1671** database connection that invoked the busy handler. Any such actions
1672** result in undefined behavior.
1673**
drh8b39db12009-02-18 18:37:58 +00001674** A busy handler must not close the database connection
1675** or [prepared statement] that invoked the busy handler.
drh2dfbbca2000-07-28 14:32:48 +00001676*/
danielk1977f9d64d22004-06-19 08:18:07 +00001677int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
drh2dfbbca2000-07-28 14:32:48 +00001678
1679/*
drhd68eee02009-12-11 03:44:18 +00001680** CAPI3REF: Set A Busy Timeout
drh6ed48bf2007-06-14 20:57:18 +00001681**
drhd68eee02009-12-11 03:44:18 +00001682** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
1683** for a specified amount of time when a table is locked. ^The handler
mihailimdb4f2ad2008-06-21 11:20:48 +00001684** will sleep multiple times until at least "ms" milliseconds of sleeping
drhd68eee02009-12-11 03:44:18 +00001685** have accumulated. ^After at least "ms" milliseconds of sleeping,
mihailimdb4f2ad2008-06-21 11:20:48 +00001686** the handler returns 0 which causes [sqlite3_step()] to return
1687** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
drh2dfbbca2000-07-28 14:32:48 +00001688**
drhd68eee02009-12-11 03:44:18 +00001689** ^Calling this routine with an argument less than or equal to zero
drh2dfbbca2000-07-28 14:32:48 +00001690** turns off all busy handlers.
drh6ed48bf2007-06-14 20:57:18 +00001691**
drhd68eee02009-12-11 03:44:18 +00001692** ^(There can only be a single busy handler for a particular
mihailimdb4f2ad2008-06-21 11:20:48 +00001693** [database connection] any any given moment. If another busy handler
1694** was defined (using [sqlite3_busy_handler()]) prior to calling
drhd68eee02009-12-11 03:44:18 +00001695** this routine, that other busy handler is cleared.)^
drh2dfbbca2000-07-28 14:32:48 +00001696*/
danielk1977f9d64d22004-06-19 08:18:07 +00001697int sqlite3_busy_timeout(sqlite3*, int ms);
drh2dfbbca2000-07-28 14:32:48 +00001698
drhe3710332000-09-29 13:30:53 +00001699/*
drhd68eee02009-12-11 03:44:18 +00001700** CAPI3REF: Convenience Routines For Running Queries
drh6ed48bf2007-06-14 20:57:18 +00001701**
drh33c1be32008-01-30 16:16:14 +00001702** Definition: A <b>result table</b> is memory data structure created by the
1703** [sqlite3_get_table()] interface. A result table records the
1704** complete query results from one or more queries.
drha18c5682000-10-08 22:20:57 +00001705**
drh33c1be32008-01-30 16:16:14 +00001706** The table conceptually has a number of rows and columns. But
1707** these numbers are not part of the result table itself. These
1708** numbers are obtained separately. Let N be the number of rows
1709** and M be the number of columns.
1710**
mihailimdb4f2ad2008-06-21 11:20:48 +00001711** A result table is an array of pointers to zero-terminated UTF-8 strings.
1712** There are (N+1)*M elements in the array. The first M pointers point
1713** to zero-terminated strings that contain the names of the columns.
1714** The remaining entries all point to query results. NULL values result
1715** in NULL pointers. All other values are in their UTF-8 zero-terminated
1716** string representation as returned by [sqlite3_column_text()].
drh33c1be32008-01-30 16:16:14 +00001717**
mihailimdb4f2ad2008-06-21 11:20:48 +00001718** A result table might consist of one or more memory allocations.
drh33c1be32008-01-30 16:16:14 +00001719** It is not safe to pass a result table directly to [sqlite3_free()].
1720** A result table should be deallocated using [sqlite3_free_table()].
1721**
1722** As an example of the result table format, suppose a query result
1723** is as follows:
drha18c5682000-10-08 22:20:57 +00001724**
drh8bacf972007-08-25 16:21:29 +00001725** <blockquote><pre>
drha18c5682000-10-08 22:20:57 +00001726** Name | Age
1727** -----------------------
1728** Alice | 43
1729** Bob | 28
1730** Cindy | 21
drh8bacf972007-08-25 16:21:29 +00001731** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001732**
drh33c1be32008-01-30 16:16:14 +00001733** There are two column (M==2) and three rows (N==3). Thus the
1734** result table has 8 entries. Suppose the result table is stored
1735** in an array names azResult. Then azResult holds this content:
drha18c5682000-10-08 22:20:57 +00001736**
drh8bacf972007-08-25 16:21:29 +00001737** <blockquote><pre>
1738** azResult&#91;0] = "Name";
1739** azResult&#91;1] = "Age";
1740** azResult&#91;2] = "Alice";
1741** azResult&#91;3] = "43";
1742** azResult&#91;4] = "Bob";
1743** azResult&#91;5] = "28";
1744** azResult&#91;6] = "Cindy";
1745** azResult&#91;7] = "21";
1746** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001747**
drhd68eee02009-12-11 03:44:18 +00001748** ^The sqlite3_get_table() function evaluates one or more
drh33c1be32008-01-30 16:16:14 +00001749** semicolon-separated SQL statements in the zero-terminated UTF-8
drhd68eee02009-12-11 03:44:18 +00001750** string of its 2nd parameter and returns a result table to the
drh33c1be32008-01-30 16:16:14 +00001751** pointer given in its 3rd parameter.
drha18c5682000-10-08 22:20:57 +00001752**
drhd68eee02009-12-11 03:44:18 +00001753** After the application has finished with the result from sqlite3_get_table(),
1754** it should pass the result table pointer to sqlite3_free_table() in order to
mihailimdb4f2ad2008-06-21 11:20:48 +00001755** release the memory that was malloced. Because of the way the
drh33c1be32008-01-30 16:16:14 +00001756** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
mihailimdb4f2ad2008-06-21 11:20:48 +00001757** function must not try to call [sqlite3_free()] directly. Only
drh33c1be32008-01-30 16:16:14 +00001758** [sqlite3_free_table()] is able to release the memory properly and safely.
drhe3710332000-09-29 13:30:53 +00001759**
drhd68eee02009-12-11 03:44:18 +00001760** ^(The sqlite3_get_table() interface is implemented as a wrapper around
drh33c1be32008-01-30 16:16:14 +00001761** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
1762** to any internal data structures of SQLite. It uses only the public
1763** interface defined here. As a consequence, errors that occur in the
1764** wrapper layer outside of the internal [sqlite3_exec()] call are not
drhd68eee02009-12-11 03:44:18 +00001765** reflected in subsequent calls to [sqlite3_errcode()] or
1766** [sqlite3_errmsg()].)^
drhe3710332000-09-29 13:30:53 +00001767*/
danielk19776f8a5032004-05-10 10:34:51 +00001768int sqlite3_get_table(
drhcf538f42008-06-27 14:51:52 +00001769 sqlite3 *db, /* An open database */
1770 const char *zSql, /* SQL to be evaluated */
1771 char ***pazResult, /* Results of the query */
1772 int *pnRow, /* Number of result rows written here */
1773 int *pnColumn, /* Number of result columns written here */
1774 char **pzErrmsg /* Error msg written here */
drhe3710332000-09-29 13:30:53 +00001775);
danielk19776f8a5032004-05-10 10:34:51 +00001776void sqlite3_free_table(char **result);
drhe3710332000-09-29 13:30:53 +00001777
drha18c5682000-10-08 22:20:57 +00001778/*
drhd68eee02009-12-11 03:44:18 +00001779** CAPI3REF: Formatted String Printing Functions
drh6ed48bf2007-06-14 20:57:18 +00001780**
shane7c7c3112009-08-17 15:31:23 +00001781** These routines are work-alikes of the "printf()" family of functions
drh6ed48bf2007-06-14 20:57:18 +00001782** from the standard C library.
1783**
drhd68eee02009-12-11 03:44:18 +00001784** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
drh6d2069d2007-08-14 01:58:53 +00001785** results into memory obtained from [sqlite3_malloc()].
drh33c1be32008-01-30 16:16:14 +00001786** The strings returned by these two routines should be
drhd68eee02009-12-11 03:44:18 +00001787** released by [sqlite3_free()]. ^Both routines return a
drh6ed48bf2007-06-14 20:57:18 +00001788** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
1789** memory to hold the resulting string.
1790**
drhd68eee02009-12-11 03:44:18 +00001791** ^(In sqlite3_snprintf() routine is similar to "snprintf()" from
drh6ed48bf2007-06-14 20:57:18 +00001792** the standard C library. The result is written into the
1793** buffer supplied as the second parameter whose size is given by
drh33c1be32008-01-30 16:16:14 +00001794** the first parameter. Note that the order of the
drhd68eee02009-12-11 03:44:18 +00001795** first two parameters is reversed from snprintf().)^ This is an
drh6ed48bf2007-06-14 20:57:18 +00001796** historical accident that cannot be fixed without breaking
drhd68eee02009-12-11 03:44:18 +00001797** backwards compatibility. ^(Note also that sqlite3_snprintf()
drh6ed48bf2007-06-14 20:57:18 +00001798** returns a pointer to its buffer instead of the number of
drhd68eee02009-12-11 03:44:18 +00001799** characters actually written into the buffer.)^ We admit that
drh6ed48bf2007-06-14 20:57:18 +00001800** the number of characters written would be a more useful return
1801** value but we cannot change the implementation of sqlite3_snprintf()
1802** now without breaking compatibility.
1803**
drhd68eee02009-12-11 03:44:18 +00001804** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
1805** guarantees that the buffer is always zero-terminated. ^The first
drh6ed48bf2007-06-14 20:57:18 +00001806** parameter "n" is the total size of the buffer, including space for
drh33c1be32008-01-30 16:16:14 +00001807** the zero terminator. So the longest string that can be completely
drh6ed48bf2007-06-14 20:57:18 +00001808** written will be n-1 characters.
1809**
1810** These routines all implement some additional formatting
drh4f26d6c2004-05-26 23:25:30 +00001811** options that are useful for constructing SQL statements.
shane26b34032008-05-23 17:21:09 +00001812** All of the usual printf() formatting options apply. In addition, there
drh153c62c2007-08-24 03:51:33 +00001813** is are "%q", "%Q", and "%z" options.
drh6ed48bf2007-06-14 20:57:18 +00001814**
drhd68eee02009-12-11 03:44:18 +00001815** ^(The %q option works like %s in that it substitutes a null-terminated
drh66b89c82000-11-28 20:47:17 +00001816** string from the argument list. But %q also doubles every '\'' character.
drhd68eee02009-12-11 03:44:18 +00001817** %q is designed for use inside a string literal.)^ By doubling each '\''
drh66b89c82000-11-28 20:47:17 +00001818** character it escapes that character and allows it to be inserted into
drha18c5682000-10-08 22:20:57 +00001819** the string.
1820**
mihailimdb4f2ad2008-06-21 11:20:48 +00001821** For example, assume the string variable zText contains text as follows:
drha18c5682000-10-08 22:20:57 +00001822**
drh6ed48bf2007-06-14 20:57:18 +00001823** <blockquote><pre>
1824** char *zText = "It's a happy day!";
1825** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001826**
drh6ed48bf2007-06-14 20:57:18 +00001827** One can use this text in an SQL statement as follows:
drha18c5682000-10-08 22:20:57 +00001828**
drh6ed48bf2007-06-14 20:57:18 +00001829** <blockquote><pre>
1830** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
1831** sqlite3_exec(db, zSQL, 0, 0, 0);
1832** sqlite3_free(zSQL);
1833** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001834**
1835** Because the %q format string is used, the '\'' character in zText
1836** is escaped and the SQL generated is as follows:
1837**
drh6ed48bf2007-06-14 20:57:18 +00001838** <blockquote><pre>
1839** INSERT INTO table1 VALUES('It''s a happy day!')
1840** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001841**
1842** This is correct. Had we used %s instead of %q, the generated SQL
1843** would have looked like this:
1844**
drh6ed48bf2007-06-14 20:57:18 +00001845** <blockquote><pre>
1846** INSERT INTO table1 VALUES('It's a happy day!');
1847** </pre></blockquote>
drha18c5682000-10-08 22:20:57 +00001848**
mihailimdb4f2ad2008-06-21 11:20:48 +00001849** This second example is an SQL syntax error. As a general rule you should
1850** always use %q instead of %s when inserting text into a string literal.
drh6ed48bf2007-06-14 20:57:18 +00001851**
drhd68eee02009-12-11 03:44:18 +00001852** ^(The %Q option works like %q except it also adds single quotes around
mihailimdb4f2ad2008-06-21 11:20:48 +00001853** the outside of the total string. Additionally, if the parameter in the
1854** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
drhd68eee02009-12-11 03:44:18 +00001855** single quotes).)^ So, for example, one could say:
drh6ed48bf2007-06-14 20:57:18 +00001856**
1857** <blockquote><pre>
1858** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
1859** sqlite3_exec(db, zSQL, 0, 0, 0);
1860** sqlite3_free(zSQL);
1861** </pre></blockquote>
1862**
1863** The code above will render a correct SQL statement in the zSQL
1864** variable even if the zText variable is a NULL pointer.
drh153c62c2007-08-24 03:51:33 +00001865**
drhd68eee02009-12-11 03:44:18 +00001866** ^(The "%z" formatting option works like "%s" but with the
drh153c62c2007-08-24 03:51:33 +00001867** addition that after the string has been read and copied into
drhd68eee02009-12-11 03:44:18 +00001868** the result, [sqlite3_free()] is called on the input string.)^
drha18c5682000-10-08 22:20:57 +00001869*/
danielk19776f8a5032004-05-10 10:34:51 +00001870char *sqlite3_mprintf(const char*,...);
1871char *sqlite3_vmprintf(const char*, va_list);
drhfeac5f82004-08-01 00:10:45 +00001872char *sqlite3_snprintf(int,char*,const char*, ...);
drh5191b7e2002-03-08 02:12:00 +00001873
drh28dd4792006-06-26 21:35:44 +00001874/*
drhd68eee02009-12-11 03:44:18 +00001875** CAPI3REF: Memory Allocation Subsystem
drhd84f9462007-08-15 11:28:56 +00001876**
drhd68eee02009-12-11 03:44:18 +00001877** The SQLite core uses these three routines for all of its own
drh33c1be32008-01-30 16:16:14 +00001878** internal memory allocation needs. "Core" in the previous sentence
drhf5befa02007-12-06 02:42:07 +00001879** does not include operating-system specific VFS implementation. The
shane26b34032008-05-23 17:21:09 +00001880** Windows VFS uses native malloc() and free() for some operations.
drhd64621d2007-11-05 17:54:17 +00001881**
drhd68eee02009-12-11 03:44:18 +00001882** ^The sqlite3_malloc() routine returns a pointer to a block
drhfddfa2d2007-12-05 18:05:16 +00001883** of memory at least N bytes in length, where N is the parameter.
drhd68eee02009-12-11 03:44:18 +00001884** ^If sqlite3_malloc() is unable to obtain sufficient free
1885** memory, it returns a NULL pointer. ^If the parameter N to
drhfddfa2d2007-12-05 18:05:16 +00001886** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
1887** a NULL pointer.
1888**
drhd68eee02009-12-11 03:44:18 +00001889** ^Calling sqlite3_free() with a pointer previously returned
drhfddfa2d2007-12-05 18:05:16 +00001890** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
drhd68eee02009-12-11 03:44:18 +00001891** that it might be reused. ^The sqlite3_free() routine is
drhfddfa2d2007-12-05 18:05:16 +00001892** a no-op if is called with a NULL pointer. Passing a NULL pointer
drh33c1be32008-01-30 16:16:14 +00001893** to sqlite3_free() is harmless. After being freed, memory
drhfddfa2d2007-12-05 18:05:16 +00001894** should neither be read nor written. Even reading previously freed
1895** memory might result in a segmentation fault or other severe error.
drh33c1be32008-01-30 16:16:14 +00001896** Memory corruption, a segmentation fault, or other severe error
drhfddfa2d2007-12-05 18:05:16 +00001897** might result if sqlite3_free() is called with a non-NULL pointer that
drh7b228b32008-10-17 15:10:37 +00001898** was not obtained from sqlite3_malloc() or sqlite3_realloc().
drhfddfa2d2007-12-05 18:05:16 +00001899**
drhd68eee02009-12-11 03:44:18 +00001900** ^(The sqlite3_realloc() interface attempts to resize a
drhfddfa2d2007-12-05 18:05:16 +00001901** prior memory allocation to be at least N bytes, where N is the
1902** second parameter. The memory allocation to be resized is the first
drhd68eee02009-12-11 03:44:18 +00001903** parameter.)^ ^ If the first parameter to sqlite3_realloc()
drhfddfa2d2007-12-05 18:05:16 +00001904** is a NULL pointer then its behavior is identical to calling
1905** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
drhd68eee02009-12-11 03:44:18 +00001906** ^If the second parameter to sqlite3_realloc() is zero or
drhfddfa2d2007-12-05 18:05:16 +00001907** negative then the behavior is exactly the same as calling
1908** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
drhd68eee02009-12-11 03:44:18 +00001909** ^sqlite3_realloc() returns a pointer to a memory allocation
drhfddfa2d2007-12-05 18:05:16 +00001910** of at least N bytes in size or NULL if sufficient memory is unavailable.
drhd68eee02009-12-11 03:44:18 +00001911** ^If M is the size of the prior allocation, then min(N,M) bytes
drhfddfa2d2007-12-05 18:05:16 +00001912** of the prior allocation are copied into the beginning of buffer returned
1913** by sqlite3_realloc() and the prior allocation is freed.
drhd68eee02009-12-11 03:44:18 +00001914** ^If sqlite3_realloc() returns NULL, then the prior allocation
drhfddfa2d2007-12-05 18:05:16 +00001915** is not freed.
1916**
drhd68eee02009-12-11 03:44:18 +00001917** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
1918** is always aligned to at least an 8 byte boundary.
drhd64621d2007-11-05 17:54:17 +00001919**
1920** In SQLite version 3.5.0 and 3.5.1, it was possible to define
1921** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
1922** implementation of these routines to be omitted. That capability
mihailimdb4f2ad2008-06-21 11:20:48 +00001923** is no longer provided. Only built-in memory allocators can be used.
drh8bacf972007-08-25 16:21:29 +00001924**
shane26b34032008-05-23 17:21:09 +00001925** The Windows OS interface layer calls
drh8bacf972007-08-25 16:21:29 +00001926** the system malloc() and free() directly when converting
1927** filenames between the UTF-8 encoding used by SQLite
shane26b34032008-05-23 17:21:09 +00001928** and whatever filename encoding is used by the particular Windows
drh8bacf972007-08-25 16:21:29 +00001929** installation. Memory allocation errors are detected, but
1930** they are reported back as [SQLITE_CANTOPEN] or
1931** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
drh33c1be32008-01-30 16:16:14 +00001932**
drh8b39db12009-02-18 18:37:58 +00001933** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
1934** must be either NULL or else pointers obtained from a prior
1935** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
1936** not yet been released.
drh33c1be32008-01-30 16:16:14 +00001937**
drh8b39db12009-02-18 18:37:58 +00001938** The application must not read or write any part of
1939** a block of memory after it has been released using
1940** [sqlite3_free()] or [sqlite3_realloc()].
drh28dd4792006-06-26 21:35:44 +00001941*/
drhf3a65f72007-08-22 20:18:21 +00001942void *sqlite3_malloc(int);
1943void *sqlite3_realloc(void*, int);
drh28dd4792006-06-26 21:35:44 +00001944void sqlite3_free(void*);
1945
drh5191b7e2002-03-08 02:12:00 +00001946/*
drhd68eee02009-12-11 03:44:18 +00001947** CAPI3REF: Memory Allocator Statistics
drhd84f9462007-08-15 11:28:56 +00001948**
drh33c1be32008-01-30 16:16:14 +00001949** SQLite provides these two interfaces for reporting on the status
1950** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
mihailimdb4f2ad2008-06-21 11:20:48 +00001951** routines, which form the built-in memory allocation subsystem.
drhd84f9462007-08-15 11:28:56 +00001952**
drhd68eee02009-12-11 03:44:18 +00001953** ^The [sqlite3_memory_used()] routine returns the number of bytes
1954** of memory currently outstanding (malloced but not freed).
1955** ^The [sqlite3_memory_highwater()] routine returns the maximum
1956** value of [sqlite3_memory_used()] since the high-water mark
1957** was last reset. ^The values returned by [sqlite3_memory_used()] and
1958** [sqlite3_memory_highwater()] include any overhead
1959** added by SQLite in its implementation of [sqlite3_malloc()],
1960** but not overhead added by the any underlying system library
1961** routines that [sqlite3_malloc()] may call.
1962**
1963** ^The memory high-water mark is reset to the current value of
1964** [sqlite3_memory_used()] if and only if the parameter to
1965** [sqlite3_memory_highwater()] is true. ^The value returned
1966** by [sqlite3_memory_highwater(1)] is the high-water mark
1967** prior to the reset.
drhd84f9462007-08-15 11:28:56 +00001968*/
drh153c62c2007-08-24 03:51:33 +00001969sqlite3_int64 sqlite3_memory_used(void);
1970sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
drhd84f9462007-08-15 11:28:56 +00001971
1972/*
drhd68eee02009-12-11 03:44:18 +00001973** CAPI3REF: Pseudo-Random Number Generator
drh2fa18682008-03-19 14:15:34 +00001974**
1975** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
drh49c3d572008-12-15 22:51:38 +00001976** select random [ROWID | ROWIDs] when inserting new records into a table that
1977** already uses the largest possible [ROWID]. The PRNG is also used for
drh2fa18682008-03-19 14:15:34 +00001978** the build-in random() and randomblob() SQL functions. This interface allows
shane26b34032008-05-23 17:21:09 +00001979** applications to access the same PRNG for other purposes.
drh2fa18682008-03-19 14:15:34 +00001980**
drhd68eee02009-12-11 03:44:18 +00001981** ^A call to this routine stores N bytes of randomness into buffer P.
drh2fa18682008-03-19 14:15:34 +00001982**
drhd68eee02009-12-11 03:44:18 +00001983** ^The first time this routine is invoked (either internally or by
drh2fa18682008-03-19 14:15:34 +00001984** the application) the PRNG is seeded using randomness obtained
1985** from the xRandomness method of the default [sqlite3_vfs] object.
drhd68eee02009-12-11 03:44:18 +00001986** ^On all subsequent invocations, the pseudo-randomness is generated
drh2fa18682008-03-19 14:15:34 +00001987** internally and without recourse to the [sqlite3_vfs] xRandomness
1988** method.
drh2fa18682008-03-19 14:15:34 +00001989*/
1990void sqlite3_randomness(int N, void *P);
1991
1992/*
drhd68eee02009-12-11 03:44:18 +00001993** CAPI3REF: Compile-Time Authorization Callbacks
drhfddfa2d2007-12-05 18:05:16 +00001994**
drhd68eee02009-12-11 03:44:18 +00001995** ^This routine registers a authorizer callback with a particular
drhf47ce562008-03-20 18:00:49 +00001996** [database connection], supplied in the first argument.
drhd68eee02009-12-11 03:44:18 +00001997** ^The authorizer callback is invoked as SQL statements are being compiled
drh6ed48bf2007-06-14 20:57:18 +00001998** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
drhd68eee02009-12-11 03:44:18 +00001999** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
drh6ed48bf2007-06-14 20:57:18 +00002000** points during the compilation process, as logic is being created
2001** to perform various actions, the authorizer callback is invoked to
drhd68eee02009-12-11 03:44:18 +00002002** see if those actions are allowed. ^The authorizer callback should
drhf47ce562008-03-20 18:00:49 +00002003** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
drh6ed48bf2007-06-14 20:57:18 +00002004** specific action but allow the SQL statement to continue to be
2005** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
drhd68eee02009-12-11 03:44:18 +00002006** rejected with an error. ^If the authorizer callback returns
drhf5befa02007-12-06 02:42:07 +00002007** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
mihailima3f64902008-06-21 13:35:56 +00002008** then the [sqlite3_prepare_v2()] or equivalent call that triggered
drh33c1be32008-01-30 16:16:14 +00002009** the authorizer will fail with an error message.
drh6ed48bf2007-06-14 20:57:18 +00002010**
drhf5befa02007-12-06 02:42:07 +00002011** When the callback returns [SQLITE_OK], that means the operation
drhd68eee02009-12-11 03:44:18 +00002012** requested is ok. ^When the callback returns [SQLITE_DENY], the
drhf5befa02007-12-06 02:42:07 +00002013** [sqlite3_prepare_v2()] or equivalent call that triggered the
drh33c1be32008-01-30 16:16:14 +00002014** authorizer will fail with an error message explaining that
drh959b5302009-04-30 15:59:56 +00002015** access is denied.
drh6ed48bf2007-06-14 20:57:18 +00002016**
drhd68eee02009-12-11 03:44:18 +00002017** ^The first parameter to the authorizer callback is a copy of the third
2018** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
mihailima3f64902008-06-21 13:35:56 +00002019** to the callback is an integer [SQLITE_COPY | action code] that specifies
drhd68eee02009-12-11 03:44:18 +00002020** the particular action to be authorized. ^The third through sixth parameters
mihailima3f64902008-06-21 13:35:56 +00002021** to the callback are zero-terminated strings that contain additional
2022** details about the action to be authorized.
drh6ed48bf2007-06-14 20:57:18 +00002023**
drhd68eee02009-12-11 03:44:18 +00002024** ^If the action code is [SQLITE_READ]
drh959b5302009-04-30 15:59:56 +00002025** and the callback returns [SQLITE_IGNORE] then the
2026** [prepared statement] statement is constructed to substitute
2027** a NULL value in place of the table column that would have
2028** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
2029** return can be used to deny an untrusted user access to individual
2030** columns of a table.
drhd68eee02009-12-11 03:44:18 +00002031** ^If the action code is [SQLITE_DELETE] and the callback returns
drh959b5302009-04-30 15:59:56 +00002032** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
2033** [truncate optimization] is disabled and all rows are deleted individually.
2034**
drhf47ce562008-03-20 18:00:49 +00002035** An authorizer is used when [sqlite3_prepare | preparing]
mihailimebe796c2008-06-21 20:11:17 +00002036** SQL statements from an untrusted source, to ensure that the SQL statements
2037** do not try to access data they are not allowed to see, or that they do not
2038** try to execute malicious statements that damage the database. For
drh6ed48bf2007-06-14 20:57:18 +00002039** example, an application may allow a user to enter arbitrary
2040** SQL queries for evaluation by a database. But the application does
2041** not want the user to be able to make arbitrary changes to the
2042** database. An authorizer could then be put in place while the
drhf47ce562008-03-20 18:00:49 +00002043** user-entered SQL is being [sqlite3_prepare | prepared] that
2044** disallows everything except [SELECT] statements.
2045**
2046** Applications that need to process SQL from untrusted sources
2047** might also consider lowering resource limits using [sqlite3_limit()]
2048** and limiting database size using the [max_page_count] [PRAGMA]
2049** in addition to using an authorizer.
drh6ed48bf2007-06-14 20:57:18 +00002050**
drhd68eee02009-12-11 03:44:18 +00002051** ^(Only a single authorizer can be in place on a database connection
drh6ed48bf2007-06-14 20:57:18 +00002052** at a time. Each call to sqlite3_set_authorizer overrides the
drhd68eee02009-12-11 03:44:18 +00002053** previous call.)^ ^Disable the authorizer by installing a NULL callback.
drh33c1be32008-01-30 16:16:14 +00002054** The authorizer is disabled by default.
drh6ed48bf2007-06-14 20:57:18 +00002055**
drhc8075422008-09-10 13:09:23 +00002056** The authorizer callback must not do anything that will modify
2057** the database connection that invoked the authorizer callback.
2058** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2059** database connections for the meaning of "modify" in this paragraph.
2060**
drhd68eee02009-12-11 03:44:18 +00002061** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
shane7c7c3112009-08-17 15:31:23 +00002062** statement might be re-prepared during [sqlite3_step()] due to a
drh7b37c5d2008-08-12 14:51:29 +00002063** schema change. Hence, the application should ensure that the
2064** correct authorizer callback remains in place during the [sqlite3_step()].
2065**
drhd68eee02009-12-11 03:44:18 +00002066** ^Note that the authorizer callback is invoked only during
drh33c1be32008-01-30 16:16:14 +00002067** [sqlite3_prepare()] or its variants. Authorization is not
drh959b5302009-04-30 15:59:56 +00002068** performed during statement evaluation in [sqlite3_step()], unless
2069** as stated in the previous paragraph, sqlite3_step() invokes
2070** sqlite3_prepare_v2() to reprepare a statement after a schema change.
drhed6c8672003-01-12 18:02:16 +00002071*/
danielk19776f8a5032004-05-10 10:34:51 +00002072int sqlite3_set_authorizer(
danielk1977f9d64d22004-06-19 08:18:07 +00002073 sqlite3*,
drhe22a3342003-04-22 20:30:37 +00002074 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
drhe5f9c642003-01-13 23:27:31 +00002075 void *pUserData
drhed6c8672003-01-12 18:02:16 +00002076);
2077
2078/*
drhd68eee02009-12-11 03:44:18 +00002079** CAPI3REF: Authorizer Return Codes
drh6ed48bf2007-06-14 20:57:18 +00002080**
2081** The [sqlite3_set_authorizer | authorizer callback function] must
2082** return either [SQLITE_OK] or one of these two constants in order
2083** to signal SQLite whether or not the action is permitted. See the
2084** [sqlite3_set_authorizer | authorizer documentation] for additional
2085** information.
2086*/
2087#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
2088#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
2089
2090/*
drhd68eee02009-12-11 03:44:18 +00002091** CAPI3REF: Authorizer Action Codes
drh6ed48bf2007-06-14 20:57:18 +00002092**
2093** The [sqlite3_set_authorizer()] interface registers a callback function
mihailima3f64902008-06-21 13:35:56 +00002094** that is invoked to authorize certain SQL statement actions. The
drh6ed48bf2007-06-14 20:57:18 +00002095** second parameter to the callback is an integer code that specifies
2096** what action is being authorized. These are the integer action codes that
drh33c1be32008-01-30 16:16:14 +00002097** the authorizer callback may be passed.
drh6ed48bf2007-06-14 20:57:18 +00002098**
mihailima3f64902008-06-21 13:35:56 +00002099** These action code values signify what kind of operation is to be
drh33c1be32008-01-30 16:16:14 +00002100** authorized. The 3rd and 4th parameters to the authorization
drhf5befa02007-12-06 02:42:07 +00002101** callback function will be parameters or NULL depending on which of these
drh7a98b852009-12-13 23:03:01 +00002102** codes is used as the second parameter. ^(The 5th parameter to the
mihailima3f64902008-06-21 13:35:56 +00002103** authorizer callback is the name of the database ("main", "temp",
drh7a98b852009-12-13 23:03:01 +00002104** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
drh5cf590c2003-04-24 01:45:04 +00002105** is the name of the inner-most trigger or view that is responsible for
mihailima3f64902008-06-21 13:35:56 +00002106** the access attempt or NULL if this access attempt is directly from
drh6ed48bf2007-06-14 20:57:18 +00002107** top-level SQL code.
drhed6c8672003-01-12 18:02:16 +00002108*/
drh6ed48bf2007-06-14 20:57:18 +00002109/******************************************* 3rd ************ 4th ***********/
drhe5f9c642003-01-13 23:27:31 +00002110#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
2111#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
2112#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
2113#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002114#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002115#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002116#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002117#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
2118#define SQLITE_DELETE 9 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002119#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002120#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002121#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002122#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002123#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002124#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
drh77ad4e42003-01-14 02:49:27 +00002125#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
drhe5f9c642003-01-13 23:27:31 +00002126#define SQLITE_DROP_VIEW 17 /* View Name NULL */
2127#define SQLITE_INSERT 18 /* Table Name NULL */
2128#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
2129#define SQLITE_READ 20 /* Table Name Column Name */
2130#define SQLITE_SELECT 21 /* NULL NULL */
danielk1977ab9b7032008-12-30 06:24:58 +00002131#define SQLITE_TRANSACTION 22 /* Operation NULL */
drhe5f9c642003-01-13 23:27:31 +00002132#define SQLITE_UPDATE 23 /* Table Name Column Name */
drh81e293b2003-06-06 19:00:42 +00002133#define SQLITE_ATTACH 24 /* Filename NULL */
2134#define SQLITE_DETACH 25 /* Database Name NULL */
danielk19771c8c23c2004-11-12 15:53:37 +00002135#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
danielk19771d54df82004-11-23 15:41:16 +00002136#define SQLITE_REINDEX 27 /* Index Name NULL */
drhe6e04962005-07-23 02:17:03 +00002137#define SQLITE_ANALYZE 28 /* Table Name NULL */
danielk1977f1a381e2006-06-16 08:01:02 +00002138#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
2139#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
drh2e904c52008-11-10 23:54:05 +00002140#define SQLITE_FUNCTION 31 /* NULL Function Name */
danielk1977ab9b7032008-12-30 06:24:58 +00002141#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
drh6ed48bf2007-06-14 20:57:18 +00002142#define SQLITE_COPY 0 /* No longer used */
drhed6c8672003-01-12 18:02:16 +00002143
2144/*
drhd68eee02009-12-11 03:44:18 +00002145** CAPI3REF: Tracing And Profiling Functions
drh6ed48bf2007-06-14 20:57:18 +00002146**
2147** These routines register callback functions that can be used for
2148** tracing and profiling the execution of SQL statements.
drhfddfa2d2007-12-05 18:05:16 +00002149**
drhd68eee02009-12-11 03:44:18 +00002150** ^The callback function registered by sqlite3_trace() is invoked at
drh33c1be32008-01-30 16:16:14 +00002151** various times when an SQL statement is being run by [sqlite3_step()].
drhd68eee02009-12-11 03:44:18 +00002152** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
2153** SQL statement text as the statement first begins executing.
2154** ^(Additional sqlite3_trace() callbacks might occur
shane26b34032008-05-23 17:21:09 +00002155** as each triggered subprogram is entered. The callbacks for triggers
drhd68eee02009-12-11 03:44:18 +00002156** contain a UTF-8 SQL comment that identifies the trigger.)^
mihailima3f64902008-06-21 13:35:56 +00002157**
drhd68eee02009-12-11 03:44:18 +00002158** ^The callback function registered by sqlite3_profile() is invoked
2159** as each SQL statement finishes. ^The profile callback contains
drh33c1be32008-01-30 16:16:14 +00002160** the original statement text and an estimate of wall-clock time
2161** of how long that statement took to run.
drh18de4822003-01-16 16:28:53 +00002162*/
drh9f8da322010-03-10 20:06:37 +00002163void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
shanea79c3cc2008-08-11 17:27:01 +00002164SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
drh6d2069d2007-08-14 01:58:53 +00002165 void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
drh18de4822003-01-16 16:28:53 +00002166
danielk1977348bb5d2003-10-18 09:37:26 +00002167/*
drhd68eee02009-12-11 03:44:18 +00002168** CAPI3REF: Query Progress Callbacks
drh6ed48bf2007-06-14 20:57:18 +00002169**
drhd68eee02009-12-11 03:44:18 +00002170** ^This routine configures a callback function - the
drhfddfa2d2007-12-05 18:05:16 +00002171** progress callback - that is invoked periodically during long
2172** running calls to [sqlite3_exec()], [sqlite3_step()] and
mihailima3f64902008-06-21 13:35:56 +00002173** [sqlite3_get_table()]. An example use for this
drh6ed48bf2007-06-14 20:57:18 +00002174** interface is to keep a GUI updated during a large query.
danielk1977348bb5d2003-10-18 09:37:26 +00002175**
drhd68eee02009-12-11 03:44:18 +00002176** ^If the progress callback returns non-zero, the operation is
drh33c1be32008-01-30 16:16:14 +00002177** interrupted. This feature can be used to implement a
drhc8075422008-09-10 13:09:23 +00002178** "Cancel" button on a GUI progress dialog box.
2179**
2180** The progress handler must not do anything that will modify
2181** the database connection that invoked the progress handler.
2182** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
2183** database connections for the meaning of "modify" in this paragraph.
danielk1977348bb5d2003-10-18 09:37:26 +00002184**
danielk1977348bb5d2003-10-18 09:37:26 +00002185*/
danielk1977f9d64d22004-06-19 08:18:07 +00002186void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
danielk1977348bb5d2003-10-18 09:37:26 +00002187
drhaa940ea2004-01-15 02:44:03 +00002188/*
drhd68eee02009-12-11 03:44:18 +00002189** CAPI3REF: Opening A New Database Connection
drhaa940ea2004-01-15 02:44:03 +00002190**
drhd68eee02009-12-11 03:44:18 +00002191** ^These routines open an SQLite database file whose name is given by the
2192** filename argument. ^The filename argument is interpreted as UTF-8 for
mihailima3f64902008-06-21 13:35:56 +00002193** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
drhd68eee02009-12-11 03:44:18 +00002194** order for sqlite3_open16(). ^(A [database connection] handle is usually
mihailima3f64902008-06-21 13:35:56 +00002195** returned in *ppDb, even if an error occurs. The only exception is that
2196** if SQLite is unable to allocate memory to hold the [sqlite3] object,
2197** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
drhd68eee02009-12-11 03:44:18 +00002198** object.)^ ^(If the database is opened (and/or created) successfully, then
2199** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
mihailima3f64902008-06-21 13:35:56 +00002200** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
drhd68eee02009-12-11 03:44:18 +00002201** an English language description of the error following a failure of any
2202** of the sqlite3_open() routines.
drh22fbcb82004-02-01 01:22:50 +00002203**
drhd68eee02009-12-11 03:44:18 +00002204** ^The default encoding for the database will be UTF-8 if
mihailima3f64902008-06-21 13:35:56 +00002205** sqlite3_open() or sqlite3_open_v2() is called and
2206** UTF-16 in the native byte order if sqlite3_open16() is used.
danielk197765904932004-05-26 06:18:37 +00002207**
drh33c1be32008-01-30 16:16:14 +00002208** Whether or not an error occurs when it is opened, resources
mihailima3f64902008-06-21 13:35:56 +00002209** associated with the [database connection] handle should be released by
2210** passing it to [sqlite3_close()] when it is no longer required.
drh6d2069d2007-08-14 01:58:53 +00002211**
mihailima3f64902008-06-21 13:35:56 +00002212** The sqlite3_open_v2() interface works like sqlite3_open()
shane26b34032008-05-23 17:21:09 +00002213** except that it accepts two additional parameters for additional control
drhd68eee02009-12-11 03:44:18 +00002214** over the new database connection. ^(The flags parameter to
2215** sqlite3_open_v2() can take one of
danielk19779a6284c2008-07-10 17:52:49 +00002216** the following three values, optionally combined with the
drhf1f12682009-09-09 14:17:52 +00002217** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
drhd68eee02009-12-11 03:44:18 +00002218** and/or [SQLITE_OPEN_PRIVATECACHE] flags:)^
drh6d2069d2007-08-14 01:58:53 +00002219**
mihailima3f64902008-06-21 13:35:56 +00002220** <dl>
drhd68eee02009-12-11 03:44:18 +00002221** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
mihailima3f64902008-06-21 13:35:56 +00002222** <dd>The database is opened in read-only mode. If the database does not
drhd68eee02009-12-11 03:44:18 +00002223** already exist, an error is returned.</dd>)^
drh6d2069d2007-08-14 01:58:53 +00002224**
drhd68eee02009-12-11 03:44:18 +00002225** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
mihailima3f64902008-06-21 13:35:56 +00002226** <dd>The database is opened for reading and writing if possible, or reading
2227** only if the file is write protected by the operating system. In either
drhd68eee02009-12-11 03:44:18 +00002228** case the database must already exist, otherwise an error is returned.</dd>)^
drh9da9d962007-08-28 15:47:44 +00002229**
drhd68eee02009-12-11 03:44:18 +00002230** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
mihailima3f64902008-06-21 13:35:56 +00002231** <dd>The database is opened for reading and writing, and is creates it if
2232** it does not already exist. This is the behavior that is always used for
drhd68eee02009-12-11 03:44:18 +00002233** sqlite3_open() and sqlite3_open16().</dd>)^
mihailima3f64902008-06-21 13:35:56 +00002234** </dl>
2235**
2236** If the 3rd parameter to sqlite3_open_v2() is not one of the
danielk19779a6284c2008-07-10 17:52:49 +00002237** combinations shown above or one of the combinations shown above combined
drhf1f12682009-09-09 14:17:52 +00002238** with the [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX],
2239** [SQLITE_OPEN_SHAREDCACHE] and/or [SQLITE_OPEN_SHAREDCACHE] flags,
drhafacce02008-09-02 21:35:03 +00002240** then the behavior is undefined.
danielk19779a6284c2008-07-10 17:52:49 +00002241**
drhd68eee02009-12-11 03:44:18 +00002242** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
drhafacce02008-09-02 21:35:03 +00002243** opens in the multi-thread [threading mode] as long as the single-thread
drhd68eee02009-12-11 03:44:18 +00002244** mode has not been set at compile-time or start-time. ^If the
drhafacce02008-09-02 21:35:03 +00002245** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
2246** in the serialized [threading mode] unless single-thread was
2247** previously selected at compile-time or start-time.
drhd68eee02009-12-11 03:44:18 +00002248** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
drhf1f12682009-09-09 14:17:52 +00002249** eligible to use [shared cache mode], regardless of whether or not shared
drhd68eee02009-12-11 03:44:18 +00002250** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
drhf1f12682009-09-09 14:17:52 +00002251** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
2252** participate in [shared cache mode] even if it is enabled.
drhd9b97cf2008-04-10 13:38:17 +00002253**
drhd68eee02009-12-11 03:44:18 +00002254** ^If the filename is ":memory:", then a private, temporary in-memory database
2255** is created for the connection. ^This in-memory database will vanish when
mihailima3f64902008-06-21 13:35:56 +00002256** the database connection is closed. Future versions of SQLite might
2257** make use of additional special filenames that begin with the ":" character.
2258** It is recommended that when a database filename actually does begin with
2259** a ":" character you should prefix the filename with a pathname such as
2260** "./" to avoid ambiguity.
drh6d2069d2007-08-14 01:58:53 +00002261**
drhd68eee02009-12-11 03:44:18 +00002262** ^If the filename is an empty string, then a private, temporary
2263** on-disk database will be created. ^This private database will be
drh3f3b6352007-09-03 20:32:45 +00002264** automatically deleted as soon as the database connection is closed.
2265**
drhd68eee02009-12-11 03:44:18 +00002266** ^The fourth parameter to sqlite3_open_v2() is the name of the
mihailima3f64902008-06-21 13:35:56 +00002267** [sqlite3_vfs] object that defines the operating system interface that
drhd68eee02009-12-11 03:44:18 +00002268** the new database connection should use. ^If the fourth parameter is
mihailima3f64902008-06-21 13:35:56 +00002269** a NULL pointer then the default [sqlite3_vfs] object is used.
drh6ed48bf2007-06-14 20:57:18 +00002270**
shane26b34032008-05-23 17:21:09 +00002271** <b>Note to Windows users:</b> The encoding used for the filename argument
mihailima3f64902008-06-21 13:35:56 +00002272** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
drh9da9d962007-08-28 15:47:44 +00002273** codepage is currently defined. Filenames containing international
2274** characters must be converted to UTF-8 prior to passing them into
mihailima3f64902008-06-21 13:35:56 +00002275** sqlite3_open() or sqlite3_open_v2().
danielk197765904932004-05-26 06:18:37 +00002276*/
2277int sqlite3_open(
2278 const char *filename, /* Database filename (UTF-8) */
danielk19774f057f92004-06-08 00:02:33 +00002279 sqlite3 **ppDb /* OUT: SQLite db handle */
danielk197765904932004-05-26 06:18:37 +00002280);
danielk197765904932004-05-26 06:18:37 +00002281int sqlite3_open16(
2282 const void *filename, /* Database filename (UTF-16) */
danielk19774f057f92004-06-08 00:02:33 +00002283 sqlite3 **ppDb /* OUT: SQLite db handle */
danielk197765904932004-05-26 06:18:37 +00002284);
drh6d2069d2007-08-14 01:58:53 +00002285int sqlite3_open_v2(
drh428e2822007-08-30 16:23:19 +00002286 const char *filename, /* Database filename (UTF-8) */
drh6d2069d2007-08-14 01:58:53 +00002287 sqlite3 **ppDb, /* OUT: SQLite db handle */
2288 int flags, /* Flags */
drhd84f9462007-08-15 11:28:56 +00002289 const char *zVfs /* Name of VFS module to use */
drh6d2069d2007-08-14 01:58:53 +00002290);
danielk1977295ba552004-05-19 10:34:51 +00002291
danielk197765904932004-05-26 06:18:37 +00002292/*
drhd68eee02009-12-11 03:44:18 +00002293** CAPI3REF: Error Codes And Messages
drh6ed48bf2007-06-14 20:57:18 +00002294**
drhd68eee02009-12-11 03:44:18 +00002295** ^The sqlite3_errcode() interface returns the numeric [result code] or
mihailimefc8e8a2008-06-21 16:47:09 +00002296** [extended result code] for the most recent failed sqlite3_* API call
2297** associated with a [database connection]. If a prior API call failed
2298** but the most recent API call succeeded, the return value from
drhd68eee02009-12-11 03:44:18 +00002299** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
drh99dfe5e2008-10-30 15:03:15 +00002300** interface is the same except that it always returns the
2301** [extended result code] even when extended result codes are
2302** disabled.
drh6ed48bf2007-06-14 20:57:18 +00002303**
drhd68eee02009-12-11 03:44:18 +00002304** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
mihailimebe796c2008-06-21 20:11:17 +00002305** text that describes the error, as either UTF-8 or UTF-16 respectively.
drhd68eee02009-12-11 03:44:18 +00002306** ^(Memory to hold the error message string is managed internally.
mihailimefc8e8a2008-06-21 16:47:09 +00002307** The application does not need to worry about freeing the result.
mlcreech27358862008-03-01 23:34:46 +00002308** However, the error string might be overwritten or deallocated by
drhd68eee02009-12-11 03:44:18 +00002309** subsequent calls to other SQLite interface functions.)^
danielk197765904932004-05-26 06:18:37 +00002310**
drh2838b472008-11-04 14:48:22 +00002311** When the serialized [threading mode] is in use, it might be the
2312** case that a second error occurs on a separate thread in between
2313** the time of the first error and the call to these interfaces.
2314** When that happens, the second error will be reported since these
2315** interfaces always report the most recent result. To avoid
2316** this, each thread can obtain exclusive use of the [database connection] D
2317** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
2318** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
2319** all calls to the interfaces listed here are completed.
2320**
drhd55d57e2008-07-07 17:53:07 +00002321** If an interface fails with SQLITE_MISUSE, that means the interface
2322** was invoked incorrectly by the application. In that case, the
2323** error code and message may or may not be set.
danielk197765904932004-05-26 06:18:37 +00002324*/
2325int sqlite3_errcode(sqlite3 *db);
drh99dfe5e2008-10-30 15:03:15 +00002326int sqlite3_extended_errcode(sqlite3 *db);
danielk197765904932004-05-26 06:18:37 +00002327const char *sqlite3_errmsg(sqlite3*);
danielk197765904932004-05-26 06:18:37 +00002328const void *sqlite3_errmsg16(sqlite3*);
2329
2330/*
drhd68eee02009-12-11 03:44:18 +00002331** CAPI3REF: SQL Statement Object
drh33c1be32008-01-30 16:16:14 +00002332** KEYWORDS: {prepared statement} {prepared statements}
drh6ed48bf2007-06-14 20:57:18 +00002333**
mihailimefc8e8a2008-06-21 16:47:09 +00002334** An instance of this object represents a single SQL statement.
2335** This object is variously known as a "prepared statement" or a
drh6ed48bf2007-06-14 20:57:18 +00002336** "compiled SQL statement" or simply as a "statement".
mihailimefc8e8a2008-06-21 16:47:09 +00002337**
drh6ed48bf2007-06-14 20:57:18 +00002338** The life of a statement object goes something like this:
2339**
2340** <ol>
2341** <li> Create the object using [sqlite3_prepare_v2()] or a related
2342** function.
mihailimefc8e8a2008-06-21 16:47:09 +00002343** <li> Bind values to [host parameters] using the sqlite3_bind_*()
2344** interfaces.
drh6ed48bf2007-06-14 20:57:18 +00002345** <li> Run the SQL by calling [sqlite3_step()] one or more times.
2346** <li> Reset the statement using [sqlite3_reset()] then go back
2347** to step 2. Do this zero or more times.
2348** <li> Destroy the object using [sqlite3_finalize()].
2349** </ol>
2350**
2351** Refer to documentation on individual methods above for additional
2352** information.
danielk197765904932004-05-26 06:18:37 +00002353*/
danielk1977fc57d7b2004-05-26 02:04:57 +00002354typedef struct sqlite3_stmt sqlite3_stmt;
2355
danielk1977e3209e42004-05-20 01:40:18 +00002356/*
drhd68eee02009-12-11 03:44:18 +00002357** CAPI3REF: Run-time Limits
drhcaa639f2008-03-20 00:32:20 +00002358**
drhd68eee02009-12-11 03:44:18 +00002359** ^(This interface allows the size of various constructs to be limited
drhcaa639f2008-03-20 00:32:20 +00002360** on a connection by connection basis. The first parameter is the
2361** [database connection] whose limit is to be set or queried. The
2362** second parameter is one of the [limit categories] that define a
2363** class of constructs to be size limited. The third parameter is the
drhd68eee02009-12-11 03:44:18 +00002364** new limit for that construct. The function returns the old limit.)^
drhcaa639f2008-03-20 00:32:20 +00002365**
drhd68eee02009-12-11 03:44:18 +00002366** ^If the new limit is a negative number, the limit is unchanged.
2367** ^(For the limit category of SQLITE_LIMIT_XYZ there is a
drhae1a8802009-02-11 15:04:40 +00002368** [limits | hard upper bound]
2369** set by a compile-time C preprocessor macro named
2370** [limits | SQLITE_MAX_XYZ].
drhd68eee02009-12-11 03:44:18 +00002371** (The "_LIMIT_" in the name is changed to "_MAX_".))^
2372** ^Attempts to increase a limit above its hard upper bound are
drh7a98b852009-12-13 23:03:01 +00002373** silently truncated to the hard upper bound.
drhcaa639f2008-03-20 00:32:20 +00002374**
drhd68eee02009-12-11 03:44:18 +00002375** Run-time limits are intended for use in applications that manage
drhbb4957f2008-03-20 14:03:29 +00002376** both their own internal database and also databases that are controlled
2377** by untrusted external sources. An example application might be a
drh46f33ef2009-02-11 15:23:35 +00002378** web browser that has its own databases for storing history and
shane26b34032008-05-23 17:21:09 +00002379** separate databases controlled by JavaScript applications downloaded
shane236ce972008-05-30 15:35:30 +00002380** off the Internet. The internal databases can be given the
drhbb4957f2008-03-20 14:03:29 +00002381** large, default limits. Databases managed by external sources can
2382** be given much smaller limits designed to prevent a denial of service
mihailimefc8e8a2008-06-21 16:47:09 +00002383** attack. Developers might also want to use the [sqlite3_set_authorizer()]
drhf47ce562008-03-20 18:00:49 +00002384** interface to further control untrusted SQL. The size of the database
2385** created by an untrusted script can be contained using the
2386** [max_page_count] [PRAGMA].
drhbb4957f2008-03-20 14:03:29 +00002387**
drha911abe2008-07-16 13:29:51 +00002388** New run-time limit categories may be added in future releases.
drhcaa639f2008-03-20 00:32:20 +00002389*/
2390int sqlite3_limit(sqlite3*, int id, int newVal);
2391
2392/*
drhd68eee02009-12-11 03:44:18 +00002393** CAPI3REF: Run-Time Limit Categories
drhe7ae4e22009-11-02 15:51:52 +00002394** KEYWORDS: {limit category} {*limit categories}
mihailimefc8e8a2008-06-21 16:47:09 +00002395**
drh46f33ef2009-02-11 15:23:35 +00002396** These constants define various performance limits
2397** that can be lowered at run-time using [sqlite3_limit()].
2398** The synopsis of the meanings of the various limits is shown below.
2399** Additional information is available at [limits | Limits in SQLite].
drhbb4957f2008-03-20 14:03:29 +00002400**
2401** <dl>
drhd68eee02009-12-11 03:44:18 +00002402** ^(<dt>SQLITE_LIMIT_LENGTH</dt>
2403** <dd>The maximum size of any string or BLOB or table row.<dd>)^
drhbb4957f2008-03-20 14:03:29 +00002404**
drhd68eee02009-12-11 03:44:18 +00002405** ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
drhdf6473a2009-12-13 22:20:08 +00002406** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002407**
drhd68eee02009-12-11 03:44:18 +00002408** ^(<dt>SQLITE_LIMIT_COLUMN</dt>
drhbb4957f2008-03-20 14:03:29 +00002409** <dd>The maximum number of columns in a table definition or in the
drh46f33ef2009-02-11 15:23:35 +00002410** result set of a [SELECT] or the maximum number of columns in an index
drhd68eee02009-12-11 03:44:18 +00002411** or in an ORDER BY or GROUP BY clause.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002412**
drhd68eee02009-12-11 03:44:18 +00002413** ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
2414** <dd>The maximum depth of the parse tree on any expression.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002415**
drhd68eee02009-12-11 03:44:18 +00002416** ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
2417** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002418**
drhd68eee02009-12-11 03:44:18 +00002419** ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
drhbb4957f2008-03-20 14:03:29 +00002420** <dd>The maximum number of instructions in a virtual machine program
drhd68eee02009-12-11 03:44:18 +00002421** used to implement an SQL statement.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002422**
drhd68eee02009-12-11 03:44:18 +00002423** ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
2424** <dd>The maximum number of arguments on a function.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002425**
drhd68eee02009-12-11 03:44:18 +00002426** ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
drh7a98b852009-12-13 23:03:01 +00002427** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
drhbb4957f2008-03-20 14:03:29 +00002428**
drh7a98b852009-12-13 23:03:01 +00002429** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
drh46f33ef2009-02-11 15:23:35 +00002430** <dd>The maximum length of the pattern argument to the [LIKE] or
drhd68eee02009-12-11 03:44:18 +00002431** [GLOB] operators.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002432**
drhd68eee02009-12-11 03:44:18 +00002433** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
drhbb4957f2008-03-20 14:03:29 +00002434** <dd>The maximum number of variables in an SQL statement that can
drhd68eee02009-12-11 03:44:18 +00002435** be bound.</dd>)^
drh417168a2009-09-07 18:14:02 +00002436**
drhd68eee02009-12-11 03:44:18 +00002437** ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
2438** <dd>The maximum depth of recursion for triggers.</dd>)^
drhbb4957f2008-03-20 14:03:29 +00002439** </dl>
drhcaa639f2008-03-20 00:32:20 +00002440*/
2441#define SQLITE_LIMIT_LENGTH 0
2442#define SQLITE_LIMIT_SQL_LENGTH 1
2443#define SQLITE_LIMIT_COLUMN 2
2444#define SQLITE_LIMIT_EXPR_DEPTH 3
2445#define SQLITE_LIMIT_COMPOUND_SELECT 4
2446#define SQLITE_LIMIT_VDBE_OP 5
2447#define SQLITE_LIMIT_FUNCTION_ARG 6
2448#define SQLITE_LIMIT_ATTACHED 7
drhb1a6c3c2008-03-20 16:30:17 +00002449#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
2450#define SQLITE_LIMIT_VARIABLE_NUMBER 9
drh417168a2009-09-07 18:14:02 +00002451#define SQLITE_LIMIT_TRIGGER_DEPTH 10
drhcaa639f2008-03-20 00:32:20 +00002452
2453/*
drhd68eee02009-12-11 03:44:18 +00002454** CAPI3REF: Compiling An SQL Statement
mihailimefc8e8a2008-06-21 16:47:09 +00002455** KEYWORDS: {SQL statement compiler}
danielk197765904932004-05-26 06:18:37 +00002456**
drh6ed48bf2007-06-14 20:57:18 +00002457** To execute an SQL query, it must first be compiled into a byte-code
mihailimefc8e8a2008-06-21 16:47:09 +00002458** program using one of these routines.
drh6ed48bf2007-06-14 20:57:18 +00002459**
mihailimefc8e8a2008-06-21 16:47:09 +00002460** The first argument, "db", is a [database connection] obtained from a
drh860e0772009-04-02 18:32:26 +00002461** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
2462** [sqlite3_open16()]. The database connection must not have been closed.
mihailimefc8e8a2008-06-21 16:47:09 +00002463**
2464** The second argument, "zSql", is the statement to be compiled, encoded
drh6ed48bf2007-06-14 20:57:18 +00002465** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
mihailimefc8e8a2008-06-21 16:47:09 +00002466** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
mihailim04bcc002008-06-22 10:21:27 +00002467** use UTF-16.
drh21f06722007-07-19 12:41:39 +00002468**
drhd68eee02009-12-11 03:44:18 +00002469** ^If the nByte argument is less than zero, then zSql is read up to the
2470** first zero terminator. ^If nByte is non-negative, then it is the maximum
2471** number of bytes read from zSql. ^When nByte is non-negative, the
mihailimefc8e8a2008-06-21 16:47:09 +00002472** zSql string ends at either the first '\000' or '\u0000' character or
drhb08c2a72008-04-16 00:28:13 +00002473** the nByte-th byte, whichever comes first. If the caller knows
danielk19773a2c8c82008-04-03 14:36:25 +00002474** that the supplied string is nul-terminated, then there is a small
mihailimefc8e8a2008-06-21 16:47:09 +00002475** performance advantage to be gained by passing an nByte parameter that
2476** is equal to the number of bytes in the input string <i>including</i>
mihailim04bcc002008-06-22 10:21:27 +00002477** the nul-terminator bytes.
danielk197765904932004-05-26 06:18:37 +00002478**
drhd68eee02009-12-11 03:44:18 +00002479** ^If pzTail is not NULL then *pzTail is made to point to the first byte
drh860e0772009-04-02 18:32:26 +00002480** past the end of the first SQL statement in zSql. These routines only
2481** compile the first statement in zSql, so *pzTail is left pointing to
2482** what remains uncompiled.
danielk197765904932004-05-26 06:18:37 +00002483**
drhd68eee02009-12-11 03:44:18 +00002484** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
2485** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
2486** to NULL. ^If the input text contains no SQL (if the input is an empty
mihailimefc8e8a2008-06-21 16:47:09 +00002487** string or a comment) then *ppStmt is set to NULL.
drh860e0772009-04-02 18:32:26 +00002488** The calling procedure is responsible for deleting the compiled
mihailimefc8e8a2008-06-21 16:47:09 +00002489** SQL statement using [sqlite3_finalize()] after it has finished with it.
drh860e0772009-04-02 18:32:26 +00002490** ppStmt may not be NULL.
danielk197765904932004-05-26 06:18:37 +00002491**
drhd68eee02009-12-11 03:44:18 +00002492** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
2493** otherwise an [error code] is returned.
drh6ed48bf2007-06-14 20:57:18 +00002494**
2495** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
2496** recommended for all new programs. The two older interfaces are retained
2497** for backwards compatibility, but their use is discouraged.
drhd68eee02009-12-11 03:44:18 +00002498** ^In the "v2" interfaces, the prepared statement
mihailimefc8e8a2008-06-21 16:47:09 +00002499** that is returned (the [sqlite3_stmt] object) contains a copy of the
mihailim04bcc002008-06-22 10:21:27 +00002500** original SQL text. This causes the [sqlite3_step()] interface to
drh481aa742009-11-05 18:46:02 +00002501** behave differently in three ways:
drh6ed48bf2007-06-14 20:57:18 +00002502**
2503** <ol>
drh33c1be32008-01-30 16:16:14 +00002504** <li>
drhd68eee02009-12-11 03:44:18 +00002505** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
drh6ed48bf2007-06-14 20:57:18 +00002506** always used to do, [sqlite3_step()] will automatically recompile the SQL
drhd68eee02009-12-11 03:44:18 +00002507** statement and try to run it again. ^If the schema has changed in
drhfddfa2d2007-12-05 18:05:16 +00002508** a way that makes the statement no longer valid, [sqlite3_step()] will still
mihailimefc8e8a2008-06-21 16:47:09 +00002509** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
2510** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
drh33c1be32008-01-30 16:16:14 +00002511** error go away. Note: use [sqlite3_errmsg()] to find the text
mihailim04bcc002008-06-22 10:21:27 +00002512** of the parsing error that results in an [SQLITE_SCHEMA] return.
drh6ed48bf2007-06-14 20:57:18 +00002513** </li>
2514**
2515** <li>
drhd68eee02009-12-11 03:44:18 +00002516** ^When an error occurs, [sqlite3_step()] will return one of the detailed
2517** [error codes] or [extended error codes]. ^The legacy behavior was that
mihailimefc8e8a2008-06-21 16:47:09 +00002518** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
drhdf6473a2009-12-13 22:20:08 +00002519** and the application would have to make a second call to [sqlite3_reset()]
2520** in order to find the underlying cause of the problem. With the "v2" prepare
mihailimefc8e8a2008-06-21 16:47:09 +00002521** interfaces, the underlying reason for the error is returned immediately.
drh6ed48bf2007-06-14 20:57:18 +00002522** </li>
drh4b5af772009-10-20 14:08:41 +00002523**
2524** <li>
2525** ^If the value of a [parameter | host parameter] in the WHERE clause might
2526** change the query plan for a statement, then the statement may be
2527** automatically recompiled (as if there had been a schema change) on the first
2528** [sqlite3_step()] call following any change to the
2529** [sqlite3_bind_text | bindings] of the [parameter].
2530** </li>
drh6ed48bf2007-06-14 20:57:18 +00002531** </ol>
danielk197765904932004-05-26 06:18:37 +00002532*/
2533int sqlite3_prepare(
2534 sqlite3 *db, /* Database handle */
2535 const char *zSql, /* SQL statement, UTF-8 encoded */
drh21f06722007-07-19 12:41:39 +00002536 int nByte, /* Maximum length of zSql in bytes. */
danielk197765904932004-05-26 06:18:37 +00002537 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2538 const char **pzTail /* OUT: Pointer to unused portion of zSql */
2539);
drh6ed48bf2007-06-14 20:57:18 +00002540int sqlite3_prepare_v2(
2541 sqlite3 *db, /* Database handle */
2542 const char *zSql, /* SQL statement, UTF-8 encoded */
drh21f06722007-07-19 12:41:39 +00002543 int nByte, /* Maximum length of zSql in bytes. */
drh6ed48bf2007-06-14 20:57:18 +00002544 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2545 const char **pzTail /* OUT: Pointer to unused portion of zSql */
2546);
danielk197765904932004-05-26 06:18:37 +00002547int sqlite3_prepare16(
2548 sqlite3 *db, /* Database handle */
2549 const void *zSql, /* SQL statement, UTF-16 encoded */
drh21f06722007-07-19 12:41:39 +00002550 int nByte, /* Maximum length of zSql in bytes. */
danielk197765904932004-05-26 06:18:37 +00002551 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2552 const void **pzTail /* OUT: Pointer to unused portion of zSql */
2553);
drhb900aaf2006-11-09 00:24:53 +00002554int sqlite3_prepare16_v2(
2555 sqlite3 *db, /* Database handle */
2556 const void *zSql, /* SQL statement, UTF-16 encoded */
drh21f06722007-07-19 12:41:39 +00002557 int nByte, /* Maximum length of zSql in bytes. */
drhb900aaf2006-11-09 00:24:53 +00002558 sqlite3_stmt **ppStmt, /* OUT: Statement handle */
2559 const void **pzTail /* OUT: Pointer to unused portion of zSql */
2560);
2561
2562/*
drhd68eee02009-12-11 03:44:18 +00002563** CAPI3REF: Retrieving Statement SQL
danielk1977d0e2a852007-11-14 06:48:48 +00002564**
drhd68eee02009-12-11 03:44:18 +00002565** ^This interface can be used to retrieve a saved copy of the original
mihailimefc8e8a2008-06-21 16:47:09 +00002566** SQL text used to create a [prepared statement] if that statement was
2567** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
danielk1977d0e2a852007-11-14 06:48:48 +00002568*/
2569const char *sqlite3_sql(sqlite3_stmt *pStmt);
2570
2571/*
drhd68eee02009-12-11 03:44:18 +00002572** CAPI3REF: Dynamically Typed Value Object
drhaa28e142008-03-18 13:47:20 +00002573** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
drh6ed48bf2007-06-14 20:57:18 +00002574**
drh33c1be32008-01-30 16:16:14 +00002575** SQLite uses the sqlite3_value object to represent all values
mihailimefc8e8a2008-06-21 16:47:09 +00002576** that can be stored in a database table. SQLite uses dynamic typing
drhd68eee02009-12-11 03:44:18 +00002577** for the values it stores. ^Values stored in sqlite3_value objects
mihailimefc8e8a2008-06-21 16:47:09 +00002578** can be integers, floating point values, strings, BLOBs, or NULL.
drhaa28e142008-03-18 13:47:20 +00002579**
2580** An sqlite3_value object may be either "protected" or "unprotected".
2581** Some interfaces require a protected sqlite3_value. Other interfaces
2582** will accept either a protected or an unprotected sqlite3_value.
mihailimefc8e8a2008-06-21 16:47:09 +00002583** Every interface that accepts sqlite3_value arguments specifies
drhaa28e142008-03-18 13:47:20 +00002584** whether or not it requires a protected sqlite3_value.
2585**
2586** The terms "protected" and "unprotected" refer to whether or not
2587** a mutex is held. A internal mutex is held for a protected
2588** sqlite3_value object but no mutex is held for an unprotected
2589** sqlite3_value object. If SQLite is compiled to be single-threaded
drh4766b292008-06-26 02:53:02 +00002590** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
drh4ead1482008-06-26 18:16:05 +00002591** or if SQLite is run in one of reduced mutex modes
2592** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
mihailimefc8e8a2008-06-21 16:47:09 +00002593** then there is no distinction between protected and unprotected
2594** sqlite3_value objects and they can be used interchangeably. However,
2595** for maximum code portability it is recommended that applications
2596** still make the distinction between between protected and unprotected
drh4ead1482008-06-26 18:16:05 +00002597** sqlite3_value objects even when not strictly required.
drhaa28e142008-03-18 13:47:20 +00002598**
drhd68eee02009-12-11 03:44:18 +00002599** ^The sqlite3_value objects that are passed as parameters into the
mihailimefc8e8a2008-06-21 16:47:09 +00002600** implementation of [application-defined SQL functions] are protected.
drhd68eee02009-12-11 03:44:18 +00002601** ^The sqlite3_value object returned by
drhaa28e142008-03-18 13:47:20 +00002602** [sqlite3_column_value()] is unprotected.
2603** Unprotected sqlite3_value objects may only be used with
mihailimefc8e8a2008-06-21 16:47:09 +00002604** [sqlite3_result_value()] and [sqlite3_bind_value()].
drhce5a5a02008-06-10 17:41:44 +00002605** The [sqlite3_value_blob | sqlite3_value_type()] family of
2606** interfaces require protected sqlite3_value objects.
drhf4479502004-05-27 03:12:53 +00002607*/
drhf4479502004-05-27 03:12:53 +00002608typedef struct Mem sqlite3_value;
2609
2610/*
drhfb434032009-12-11 23:11:26 +00002611** CAPI3REF: SQL Function Context Object
drh4f26d6c2004-05-26 23:25:30 +00002612**
drh6ed48bf2007-06-14 20:57:18 +00002613** The context in which an SQL function executes is stored in an
drhd68eee02009-12-11 03:44:18 +00002614** sqlite3_context object. ^A pointer to an sqlite3_context object
mihailimefc8e8a2008-06-21 16:47:09 +00002615** is always first parameter to [application-defined SQL functions].
2616** The application-defined SQL function implementation will pass this
2617** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
2618** [sqlite3_aggregate_context()], [sqlite3_user_data()],
2619** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
2620** and/or [sqlite3_set_auxdata()].
drh6ed48bf2007-06-14 20:57:18 +00002621*/
2622typedef struct sqlite3_context sqlite3_context;
2623
2624/*
drhfb434032009-12-11 23:11:26 +00002625** CAPI3REF: Binding Values To Prepared Statements
mihailimefc8e8a2008-06-21 16:47:09 +00002626** KEYWORDS: {host parameter} {host parameters} {host parameter name}
mihailimebe796c2008-06-21 20:11:17 +00002627** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
drh6ed48bf2007-06-14 20:57:18 +00002628**
drhd68eee02009-12-11 03:44:18 +00002629** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
drh333ceb92009-08-25 14:59:37 +00002630** literals may be replaced by a [parameter] that matches one of following
2631** templates:
drh6ed48bf2007-06-14 20:57:18 +00002632**
2633** <ul>
2634** <li> ?
2635** <li> ?NNN
drh33c1be32008-01-30 16:16:14 +00002636** <li> :VVV
2637** <li> @VVV
drh6ed48bf2007-06-14 20:57:18 +00002638** <li> $VVV
2639** </ul>
2640**
drh333ceb92009-08-25 14:59:37 +00002641** In the templates above, NNN represents an integer literal,
drhd68eee02009-12-11 03:44:18 +00002642** and VVV represents an alphanumeric identifer.)^ ^The values of these
mihailimefc8e8a2008-06-21 16:47:09 +00002643** parameters (also called "host parameter names" or "SQL parameters")
drh6ed48bf2007-06-14 20:57:18 +00002644** can be set using the sqlite3_bind_*() routines defined here.
2645**
drhd68eee02009-12-11 03:44:18 +00002646** ^The first argument to the sqlite3_bind_*() routines is always
mihailimefc8e8a2008-06-21 16:47:09 +00002647** a pointer to the [sqlite3_stmt] object returned from
2648** [sqlite3_prepare_v2()] or its variants.
2649**
drhd68eee02009-12-11 03:44:18 +00002650** ^The second argument is the index of the SQL parameter to be set.
2651** ^The leftmost SQL parameter has an index of 1. ^When the same named
mihailimefc8e8a2008-06-21 16:47:09 +00002652** SQL parameter is used more than once, second and subsequent
2653** occurrences have the same index as the first occurrence.
drhd68eee02009-12-11 03:44:18 +00002654** ^The index for named parameters can be looked up using the
2655** [sqlite3_bind_parameter_index()] API if desired. ^The index
drhf5befa02007-12-06 02:42:07 +00002656** for "?NNN" parameters is the value of NNN.
drhd68eee02009-12-11 03:44:18 +00002657** ^The NNN value must be between 1 and the [sqlite3_limit()]
drh4ead1482008-06-26 18:16:05 +00002658** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
drh6ed48bf2007-06-14 20:57:18 +00002659**
drhd68eee02009-12-11 03:44:18 +00002660** ^The third argument is the value to bind to the parameter.
drh6ed48bf2007-06-14 20:57:18 +00002661**
drhd68eee02009-12-11 03:44:18 +00002662** ^(In those routines that have a fourth argument, its value is the
mihailimefc8e8a2008-06-21 16:47:09 +00002663** number of bytes in the parameter. To be clear: the value is the
drhd68eee02009-12-11 03:44:18 +00002664** number of <u>bytes</u> in the value, not the number of characters.)^
2665** ^If the fourth parameter is negative, the length of the string is
shane26b34032008-05-23 17:21:09 +00002666** the number of bytes up to the first zero terminator.
drh4f26d6c2004-05-26 23:25:30 +00002667**
drhd68eee02009-12-11 03:44:18 +00002668** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
drh900dfba2004-07-21 15:21:36 +00002669** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
drhd68eee02009-12-11 03:44:18 +00002670** string after SQLite has finished with it. ^If the fifth argument is
drh33c1be32008-01-30 16:16:14 +00002671** the special value [SQLITE_STATIC], then SQLite assumes that the
drhfddfa2d2007-12-05 18:05:16 +00002672** information is in static, unmanaged space and does not need to be freed.
drhd68eee02009-12-11 03:44:18 +00002673** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
drhfddfa2d2007-12-05 18:05:16 +00002674** SQLite makes its own private copy of the data immediately, before
drh33c1be32008-01-30 16:16:14 +00002675** the sqlite3_bind_*() routine returns.
drh4f26d6c2004-05-26 23:25:30 +00002676**
drhd68eee02009-12-11 03:44:18 +00002677** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
2678** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
mihailimefc8e8a2008-06-21 16:47:09 +00002679** (just an integer to hold its size) while it is being processed.
shane26b34032008-05-23 17:21:09 +00002680** Zeroblobs are intended to serve as placeholders for BLOBs whose
mihailimefc8e8a2008-06-21 16:47:09 +00002681** content is later written using
2682** [sqlite3_blob_open | incremental BLOB I/O] routines.
drhd68eee02009-12-11 03:44:18 +00002683** ^A negative value for the zeroblob results in a zero-length BLOB.
drh6ed48bf2007-06-14 20:57:18 +00002684**
drhd68eee02009-12-11 03:44:18 +00002685** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
2686** for the [prepared statement] or with a prepared statement for which
2687** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
2688** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
2689** routine is passed a [prepared statement] that has been finalized, the
2690** result is undefined and probably harmful.
drh6ed48bf2007-06-14 20:57:18 +00002691**
drhd68eee02009-12-11 03:44:18 +00002692** ^Bindings are not cleared by the [sqlite3_reset()] routine.
2693** ^Unbound parameters are interpreted as NULL.
2694**
2695** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
2696** [error code] if anything goes wrong.
2697** ^[SQLITE_RANGE] is returned if the parameter
2698** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
drh33c1be32008-01-30 16:16:14 +00002699**
2700** See also: [sqlite3_bind_parameter_count()],
mihailimefc8e8a2008-06-21 16:47:09 +00002701** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
drh4f26d6c2004-05-26 23:25:30 +00002702*/
danielk1977d8123362004-06-12 09:25:12 +00002703int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
drhf4479502004-05-27 03:12:53 +00002704int sqlite3_bind_double(sqlite3_stmt*, int, double);
2705int sqlite3_bind_int(sqlite3_stmt*, int, int);
drh6d2069d2007-08-14 01:58:53 +00002706int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
drhf4479502004-05-27 03:12:53 +00002707int sqlite3_bind_null(sqlite3_stmt*, int);
danielk1977d8123362004-06-12 09:25:12 +00002708int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
2709int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
drhf4479502004-05-27 03:12:53 +00002710int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
drhb026e052007-05-02 01:34:31 +00002711int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
drh4f26d6c2004-05-26 23:25:30 +00002712
2713/*
drhd68eee02009-12-11 03:44:18 +00002714** CAPI3REF: Number Of SQL Parameters
drh6ed48bf2007-06-14 20:57:18 +00002715**
drhd68eee02009-12-11 03:44:18 +00002716** ^This routine can be used to find the number of [SQL parameters]
mihailimefc8e8a2008-06-21 16:47:09 +00002717** in a [prepared statement]. SQL parameters are tokens of the
drh33c1be32008-01-30 16:16:14 +00002718** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
shane26b34032008-05-23 17:21:09 +00002719** placeholders for values that are [sqlite3_bind_blob | bound]
drh33c1be32008-01-30 16:16:14 +00002720** to the parameters at a later time.
drh605264d2007-08-21 15:13:19 +00002721**
drhd68eee02009-12-11 03:44:18 +00002722** ^(This routine actually returns the index of the largest (rightmost)
mihailimefc8e8a2008-06-21 16:47:09 +00002723** parameter. For all forms except ?NNN, this will correspond to the
drhd68eee02009-12-11 03:44:18 +00002724** number of unique parameters. If parameters of the ?NNN form are used,
2725** there may be gaps in the list.)^
drh33c1be32008-01-30 16:16:14 +00002726**
2727** See also: [sqlite3_bind_blob|sqlite3_bind()],
2728** [sqlite3_bind_parameter_name()], and
2729** [sqlite3_bind_parameter_index()].
drh75f6a032004-07-15 14:15:00 +00002730*/
2731int sqlite3_bind_parameter_count(sqlite3_stmt*);
2732
2733/*
drhd68eee02009-12-11 03:44:18 +00002734** CAPI3REF: Name Of A Host Parameter
drh6ed48bf2007-06-14 20:57:18 +00002735**
drhd68eee02009-12-11 03:44:18 +00002736** ^The sqlite3_bind_parameter_name(P,N) interface returns
2737** the name of the N-th [SQL parameter] in the [prepared statement] P.
2738** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
drhe1b3e802008-04-27 22:29:01 +00002739** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
2740** respectively.
2741** In other words, the initial ":" or "$" or "@" or "?"
drhd68eee02009-12-11 03:44:18 +00002742** is included as part of the name.)^
2743** ^Parameters of the form "?" without a following integer have no name
drhdf6473a2009-12-13 22:20:08 +00002744** and are referred to as "nameless" or "anonymous parameters".
drh6ed48bf2007-06-14 20:57:18 +00002745**
drhd68eee02009-12-11 03:44:18 +00002746** ^The first host parameter has an index of 1, not 0.
drh6ed48bf2007-06-14 20:57:18 +00002747**
drhd68eee02009-12-11 03:44:18 +00002748** ^If the value N is out of range or if the N-th parameter is
2749** nameless, then NULL is returned. ^The returned string is
mihailimefc8e8a2008-06-21 16:47:09 +00002750** always in UTF-8 encoding even if the named parameter was
drhfddfa2d2007-12-05 18:05:16 +00002751** originally specified as UTF-16 in [sqlite3_prepare16()] or
2752** [sqlite3_prepare16_v2()].
drh33c1be32008-01-30 16:16:14 +00002753**
2754** See also: [sqlite3_bind_blob|sqlite3_bind()],
2755** [sqlite3_bind_parameter_count()], and
2756** [sqlite3_bind_parameter_index()].
drh895d7472004-08-20 16:02:39 +00002757*/
2758const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
2759
2760/*
drhd68eee02009-12-11 03:44:18 +00002761** CAPI3REF: Index Of A Parameter With A Given Name
drh6ed48bf2007-06-14 20:57:18 +00002762**
drhd68eee02009-12-11 03:44:18 +00002763** ^Return the index of an SQL parameter given its name. ^The
drh33c1be32008-01-30 16:16:14 +00002764** index value returned is suitable for use as the second
drhd68eee02009-12-11 03:44:18 +00002765** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
2766** is returned if no matching parameter is found. ^The parameter
drh33c1be32008-01-30 16:16:14 +00002767** name must be given in UTF-8 even if the original statement
2768** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
2769**
2770** See also: [sqlite3_bind_blob|sqlite3_bind()],
2771** [sqlite3_bind_parameter_count()], and
2772** [sqlite3_bind_parameter_index()].
drhfa6bc002004-09-07 16:19:52 +00002773*/
2774int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
2775
2776/*
drhd68eee02009-12-11 03:44:18 +00002777** CAPI3REF: Reset All Bindings On A Prepared Statement
drh6ed48bf2007-06-14 20:57:18 +00002778**
drhd68eee02009-12-11 03:44:18 +00002779** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
mihailimefc8e8a2008-06-21 16:47:09 +00002780** the [sqlite3_bind_blob | bindings] on a [prepared statement].
drhd68eee02009-12-11 03:44:18 +00002781** ^Use this routine to reset all host parameters to NULL.
danielk1977600dd0b2005-01-20 01:14:23 +00002782*/
2783int sqlite3_clear_bindings(sqlite3_stmt*);
2784
2785/*
drhd68eee02009-12-11 03:44:18 +00002786** CAPI3REF: Number Of Columns In A Result Set
drh6ed48bf2007-06-14 20:57:18 +00002787**
drhd68eee02009-12-11 03:44:18 +00002788** ^Return the number of columns in the result set returned by the
2789** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
drh4ead1482008-06-26 18:16:05 +00002790** statement that does not return data (for example an [UPDATE]).
danielk197765904932004-05-26 06:18:37 +00002791*/
2792int sqlite3_column_count(sqlite3_stmt *pStmt);
2793
2794/*
drhd68eee02009-12-11 03:44:18 +00002795** CAPI3REF: Column Names In A Result Set
drh6ed48bf2007-06-14 20:57:18 +00002796**
drhd68eee02009-12-11 03:44:18 +00002797** ^These routines return the name assigned to a particular column
2798** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
mihailimefc8e8a2008-06-21 16:47:09 +00002799** interface returns a pointer to a zero-terminated UTF-8 string
drhf5befa02007-12-06 02:42:07 +00002800** and sqlite3_column_name16() returns a pointer to a zero-terminated
drhd68eee02009-12-11 03:44:18 +00002801** UTF-16 string. ^The first parameter is the [prepared statement]
2802** that implements the [SELECT] statement. ^The second parameter is the
2803** column number. ^The leftmost column is number 0.
drh6ed48bf2007-06-14 20:57:18 +00002804**
drhd68eee02009-12-11 03:44:18 +00002805** ^The returned string pointer is valid until either the [prepared statement]
mihailimefc8e8a2008-06-21 16:47:09 +00002806** is destroyed by [sqlite3_finalize()] or until the next call to
2807** sqlite3_column_name() or sqlite3_column_name16() on the same column.
drh4a50aac2007-08-23 02:47:53 +00002808**
drhd68eee02009-12-11 03:44:18 +00002809** ^If sqlite3_malloc() fails during the processing of either routine
drh4a50aac2007-08-23 02:47:53 +00002810** (for example during a conversion from UTF-8 to UTF-16) then a
2811** NULL pointer is returned.
drh33c1be32008-01-30 16:16:14 +00002812**
drhd68eee02009-12-11 03:44:18 +00002813** ^The name of a result column is the value of the "AS" clause for
drh33c1be32008-01-30 16:16:14 +00002814** that column, if there is an AS clause. If there is no AS clause
2815** then the name of the column is unspecified and may change from
2816** one release of SQLite to the next.
danielk197765904932004-05-26 06:18:37 +00002817*/
drh6ed48bf2007-06-14 20:57:18 +00002818const char *sqlite3_column_name(sqlite3_stmt*, int N);
2819const void *sqlite3_column_name16(sqlite3_stmt*, int N);
danielk197765904932004-05-26 06:18:37 +00002820
2821/*
drhd68eee02009-12-11 03:44:18 +00002822** CAPI3REF: Source Of Data In A Query Result
drh6ed48bf2007-06-14 20:57:18 +00002823**
drh9be37f62009-12-12 23:57:36 +00002824** ^These routines provide a means to determine the database, table, and
2825** table column that is the origin of a particular result column in
2826** [SELECT] statement.
drhd68eee02009-12-11 03:44:18 +00002827** ^The name of the database or table or column can be returned as
2828** either a UTF-8 or UTF-16 string. ^The _database_ routines return
drhbf2564f2007-06-21 15:25:05 +00002829** the database name, the _table_ routines return the table name, and
drh33c1be32008-01-30 16:16:14 +00002830** the origin_ routines return the column name.
drhd68eee02009-12-11 03:44:18 +00002831** ^The returned string is valid until the [prepared statement] is destroyed
mihailim1c492652008-06-21 18:02:16 +00002832** using [sqlite3_finalize()] or until the same information is requested
drhbf2564f2007-06-21 15:25:05 +00002833** again in a different encoding.
2834**
drhd68eee02009-12-11 03:44:18 +00002835** ^The names returned are the original un-aliased names of the
drhbf2564f2007-06-21 15:25:05 +00002836** database, table, and column.
drh6ed48bf2007-06-14 20:57:18 +00002837**
drh9be37f62009-12-12 23:57:36 +00002838** ^The first argument to these interfaces is a [prepared statement].
2839** ^These functions return information about the Nth result column returned by
danielk1977955de522006-02-10 02:27:42 +00002840** the statement, where N is the second function argument.
drh9be37f62009-12-12 23:57:36 +00002841** ^The left-most column is column 0 for these routines.
danielk1977955de522006-02-10 02:27:42 +00002842**
drhd68eee02009-12-11 03:44:18 +00002843** ^If the Nth column returned by the statement is an expression or
mihailim1c492652008-06-21 18:02:16 +00002844** subquery and is not a column value, then all of these functions return
drhd68eee02009-12-11 03:44:18 +00002845** NULL. ^These routine might also return NULL if a memory allocation error
drhdf6473a2009-12-13 22:20:08 +00002846** occurs. ^Otherwise, they return the name of the attached database, table,
drhd68eee02009-12-11 03:44:18 +00002847** or column that query result column was extracted from.
danielk1977955de522006-02-10 02:27:42 +00002848**
drh9be37f62009-12-12 23:57:36 +00002849** ^As with all other SQLite APIs, those whose names end with "16" return
2850** UTF-16 encoded strings and the other functions return UTF-8.
danielk19774b1ae992006-02-10 03:06:10 +00002851**
drhd68eee02009-12-11 03:44:18 +00002852** ^These APIs are only available if the library was compiled with the
drh9be37f62009-12-12 23:57:36 +00002853** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
drh32bc3f62007-08-21 20:25:39 +00002854**
2855** If two or more threads call one or more of these routines against the same
2856** prepared statement and column at the same time then the results are
2857** undefined.
drh33c1be32008-01-30 16:16:14 +00002858**
drh8b39db12009-02-18 18:37:58 +00002859** If two or more threads call one or more
2860** [sqlite3_column_database_name | column metadata interfaces]
2861** for the same [prepared statement] and result column
2862** at the same time then the results are undefined.
danielk1977955de522006-02-10 02:27:42 +00002863*/
2864const char *sqlite3_column_database_name(sqlite3_stmt*,int);
2865const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
2866const char *sqlite3_column_table_name(sqlite3_stmt*,int);
2867const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
2868const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
2869const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
2870
2871/*
drhd68eee02009-12-11 03:44:18 +00002872** CAPI3REF: Declared Datatype Of A Query Result
drh6ed48bf2007-06-14 20:57:18 +00002873**
drhd68eee02009-12-11 03:44:18 +00002874** ^(The first parameter is a [prepared statement].
drh4ead1482008-06-26 18:16:05 +00002875** If this statement is a [SELECT] statement and the Nth column of the
2876** returned result set of that [SELECT] is a table column (not an
drh6ed48bf2007-06-14 20:57:18 +00002877** expression or subquery) then the declared type of the table
drhdf6473a2009-12-13 22:20:08 +00002878** column is returned.)^ ^If the Nth column of the result set is an
drh6ed48bf2007-06-14 20:57:18 +00002879** expression or subquery, then a NULL pointer is returned.
drhd68eee02009-12-11 03:44:18 +00002880** ^The returned string is always UTF-8 encoded.
mihailim1c492652008-06-21 18:02:16 +00002881**
drhd68eee02009-12-11 03:44:18 +00002882** ^(For example, given the database schema:
danielk197765904932004-05-26 06:18:37 +00002883**
2884** CREATE TABLE t1(c1 VARIANT);
2885**
mihailim1c492652008-06-21 18:02:16 +00002886** and the following statement to be compiled:
danielk197765904932004-05-26 06:18:37 +00002887**
danielk1977955de522006-02-10 02:27:42 +00002888** SELECT c1 + 1, c1 FROM t1;
danielk197765904932004-05-26 06:18:37 +00002889**
mihailim1c492652008-06-21 18:02:16 +00002890** this routine would return the string "VARIANT" for the second result
drhd68eee02009-12-11 03:44:18 +00002891** column (i==1), and a NULL pointer for the first result column (i==0).)^
drh6ed48bf2007-06-14 20:57:18 +00002892**
drhd68eee02009-12-11 03:44:18 +00002893** ^SQLite uses dynamic run-time typing. ^So just because a column
drh6ed48bf2007-06-14 20:57:18 +00002894** is declared to contain a particular type does not mean that the
2895** data stored in that column is of the declared type. SQLite is
drhd68eee02009-12-11 03:44:18 +00002896** strongly typed, but the typing is dynamic not static. ^Type
drh6ed48bf2007-06-14 20:57:18 +00002897** is associated with individual values, not with the containers
2898** used to hold those values.
danielk197765904932004-05-26 06:18:37 +00002899*/
drh33c1be32008-01-30 16:16:14 +00002900const char *sqlite3_column_decltype(sqlite3_stmt*,int);
danielk197765904932004-05-26 06:18:37 +00002901const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
2902
mihailimebe796c2008-06-21 20:11:17 +00002903/*
drhd68eee02009-12-11 03:44:18 +00002904** CAPI3REF: Evaluate An SQL Statement
danielk1977106bb232004-05-21 10:08:53 +00002905**
mihailim1c492652008-06-21 18:02:16 +00002906** After a [prepared statement] has been prepared using either
2907** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
2908** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
2909** must be called one or more times to evaluate the statement.
danielk1977106bb232004-05-21 10:08:53 +00002910**
mihailim1c492652008-06-21 18:02:16 +00002911** The details of the behavior of the sqlite3_step() interface depend
drh6ed48bf2007-06-14 20:57:18 +00002912** on whether the statement was prepared using the newer "v2" interface
2913** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
2914** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
2915** new "v2" interface is recommended for new applications but the legacy
2916** interface will continue to be supported.
danielk1977106bb232004-05-21 10:08:53 +00002917**
drhd68eee02009-12-11 03:44:18 +00002918** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
drh6ed48bf2007-06-14 20:57:18 +00002919** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
drhd68eee02009-12-11 03:44:18 +00002920** ^With the "v2" interface, any of the other [result codes] or
mihailim1c492652008-06-21 18:02:16 +00002921** [extended result codes] might be returned as well.
drh6ed48bf2007-06-14 20:57:18 +00002922**
drhd68eee02009-12-11 03:44:18 +00002923** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
2924** database locks it needs to do its job. ^If the statement is a [COMMIT]
drh6ed48bf2007-06-14 20:57:18 +00002925** or occurs outside of an explicit transaction, then you can retry the
drh4ead1482008-06-26 18:16:05 +00002926** statement. If the statement is not a [COMMIT] and occurs within a
drh6ed48bf2007-06-14 20:57:18 +00002927** explicit transaction then you should rollback the transaction before
2928** continuing.
2929**
drhd68eee02009-12-11 03:44:18 +00002930** ^[SQLITE_DONE] means that the statement has finished executing
danielk1977106bb232004-05-21 10:08:53 +00002931** successfully. sqlite3_step() should not be called again on this virtual
drh6ed48bf2007-06-14 20:57:18 +00002932** machine without first calling [sqlite3_reset()] to reset the virtual
2933** machine back to its initial state.
danielk1977106bb232004-05-21 10:08:53 +00002934**
drhd68eee02009-12-11 03:44:18 +00002935** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
mihailim1c492652008-06-21 18:02:16 +00002936** is returned each time a new row of data is ready for processing by the
2937** caller. The values may be accessed using the [column access functions].
drh6ed48bf2007-06-14 20:57:18 +00002938** sqlite3_step() is called again to retrieve the next row of data.
mihailim1c492652008-06-21 18:02:16 +00002939**
drhd68eee02009-12-11 03:44:18 +00002940** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
danielk1977106bb232004-05-21 10:08:53 +00002941** violation) has occurred. sqlite3_step() should not be called again on
drh6ed48bf2007-06-14 20:57:18 +00002942** the VM. More information may be found by calling [sqlite3_errmsg()].
drhd68eee02009-12-11 03:44:18 +00002943** ^With the legacy interface, a more specific error code (for example,
drh6ed48bf2007-06-14 20:57:18 +00002944** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
2945** can be obtained by calling [sqlite3_reset()] on the
drhd68eee02009-12-11 03:44:18 +00002946** [prepared statement]. ^In the "v2" interface,
drh6ed48bf2007-06-14 20:57:18 +00002947** the more specific error code is returned directly by sqlite3_step().
danielk1977106bb232004-05-21 10:08:53 +00002948**
drh6ed48bf2007-06-14 20:57:18 +00002949** [SQLITE_MISUSE] means that the this routine was called inappropriately.
drh33c1be32008-01-30 16:16:14 +00002950** Perhaps it was called on a [prepared statement] that has
mihailim1c492652008-06-21 18:02:16 +00002951** already been [sqlite3_finalize | finalized] or on one that had
drh6ed48bf2007-06-14 20:57:18 +00002952** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
2953** be the case that the same database connection is being used by two or
2954** more threads at the same moment in time.
2955**
drh3674bfd2010-04-17 12:53:19 +00002956** For all versions of SQLite up to and including 3.6.23.1, it was required
2957** after sqlite3_step() returned anything other than [SQLITE_ROW] that
2958** [sqlite3_reset()] be called before any subsequent invocation of
2959** sqlite3_step(). Failure to invoke [sqlite3_reset()] in this way would
2960** result in an [SQLITE_MISUSE] return from sqlite3_step(). But after
2961** version 3.6.23.1, sqlite3_step() began calling [sqlite3_reset()]
2962** automatically in this circumstance rather than returning [SQLITE_MISUSE].
2963**
mihailim1c492652008-06-21 18:02:16 +00002964** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
2965** API always returns a generic error code, [SQLITE_ERROR], following any
2966** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
2967** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
2968** specific [error codes] that better describes the error.
drh6ed48bf2007-06-14 20:57:18 +00002969** We admit that this is a goofy design. The problem has been fixed
2970** with the "v2" interface. If you prepare all of your SQL statements
2971** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
mihailim1c492652008-06-21 18:02:16 +00002972** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
2973** then the more specific [error codes] are returned directly
drh6ed48bf2007-06-14 20:57:18 +00002974** by sqlite3_step(). The use of the "v2" interface is recommended.
danielk1977106bb232004-05-21 10:08:53 +00002975*/
danielk197717240fd2004-05-26 00:07:25 +00002976int sqlite3_step(sqlite3_stmt*);
danielk1977106bb232004-05-21 10:08:53 +00002977
danielk1977106bb232004-05-21 10:08:53 +00002978/*
drhd68eee02009-12-11 03:44:18 +00002979** CAPI3REF: Number of columns in a result set
drh6ed48bf2007-06-14 20:57:18 +00002980**
drhfb434032009-12-11 23:11:26 +00002981** ^The sqlite3_data_count(P) the number of columns in the
2982** of the result set of [prepared statement] P.
danielk1977106bb232004-05-21 10:08:53 +00002983*/
danielk197793d46752004-05-23 13:30:58 +00002984int sqlite3_data_count(sqlite3_stmt *pStmt);
danielk19774adee202004-05-08 08:23:19 +00002985
drh4f26d6c2004-05-26 23:25:30 +00002986/*
drhd68eee02009-12-11 03:44:18 +00002987** CAPI3REF: Fundamental Datatypes
drh33c1be32008-01-30 16:16:14 +00002988** KEYWORDS: SQLITE_TEXT
drh6ed48bf2007-06-14 20:57:18 +00002989**
drhfb434032009-12-11 23:11:26 +00002990** ^(Every value in SQLite has one of five fundamental datatypes:
drh6ed48bf2007-06-14 20:57:18 +00002991**
2992** <ul>
2993** <li> 64-bit signed integer
2994** <li> 64-bit IEEE floating point number
2995** <li> string
2996** <li> BLOB
2997** <li> NULL
drhfb434032009-12-11 23:11:26 +00002998** </ul>)^
drh6ed48bf2007-06-14 20:57:18 +00002999**
3000** These constants are codes for each of those types.
3001**
3002** Note that the SQLITE_TEXT constant was also used in SQLite version 2
3003** for a completely different meaning. Software that links against both
mihailim1c492652008-06-21 18:02:16 +00003004** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
drh6ed48bf2007-06-14 20:57:18 +00003005** SQLITE_TEXT.
drh4f26d6c2004-05-26 23:25:30 +00003006*/
drh9c054832004-05-31 18:51:57 +00003007#define SQLITE_INTEGER 1
3008#define SQLITE_FLOAT 2
drh9c054832004-05-31 18:51:57 +00003009#define SQLITE_BLOB 4
3010#define SQLITE_NULL 5
drh1e284f42004-10-06 15:52:01 +00003011#ifdef SQLITE_TEXT
3012# undef SQLITE_TEXT
3013#else
3014# define SQLITE_TEXT 3
3015#endif
3016#define SQLITE3_TEXT 3
3017
3018/*
drhd68eee02009-12-11 03:44:18 +00003019** CAPI3REF: Result Values From A Query
mihailim1c492652008-06-21 18:02:16 +00003020** KEYWORDS: {column access functions}
drh6ed48bf2007-06-14 20:57:18 +00003021**
drhd68eee02009-12-11 03:44:18 +00003022** These routines form the "result set" interface.
drh33c1be32008-01-30 16:16:14 +00003023**
drhd68eee02009-12-11 03:44:18 +00003024** ^These routines return information about a single column of the current
3025** result row of a query. ^In every case the first argument is a pointer
mihailim1c492652008-06-21 18:02:16 +00003026** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
3027** that was returned from [sqlite3_prepare_v2()] or one of its variants)
3028** and the second argument is the index of the column for which information
drhd68eee02009-12-11 03:44:18 +00003029** should be returned. ^The leftmost column of the result set has the index 0.
3030** ^The number of columns in the result can be determined using
drhedc17552009-10-22 00:14:05 +00003031** [sqlite3_column_count()].
danielk1977106bb232004-05-21 10:08:53 +00003032**
mihailim1c492652008-06-21 18:02:16 +00003033** If the SQL statement does not currently point to a valid row, or if the
3034** column index is out of range, the result is undefined.
drh32bc3f62007-08-21 20:25:39 +00003035** These routines may only be called when the most recent call to
3036** [sqlite3_step()] has returned [SQLITE_ROW] and neither
mihailim1c492652008-06-21 18:02:16 +00003037** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
drh32bc3f62007-08-21 20:25:39 +00003038** If any of these routines are called after [sqlite3_reset()] or
3039** [sqlite3_finalize()] or after [sqlite3_step()] has returned
3040** something other than [SQLITE_ROW], the results are undefined.
3041** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
3042** are called from a different thread while any of these routines
mihailim1c492652008-06-21 18:02:16 +00003043** are pending, then the results are undefined.
drh6ed48bf2007-06-14 20:57:18 +00003044**
drhd68eee02009-12-11 03:44:18 +00003045** ^The sqlite3_column_type() routine returns the
drh6ed48bf2007-06-14 20:57:18 +00003046** [SQLITE_INTEGER | datatype code] for the initial data type
drhd68eee02009-12-11 03:44:18 +00003047** of the result column. ^The returned value is one of [SQLITE_INTEGER],
drh6ed48bf2007-06-14 20:57:18 +00003048** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
3049** returned by sqlite3_column_type() is only meaningful if no type
3050** conversions have occurred as described below. After a type conversion,
3051** the value returned by sqlite3_column_type() is undefined. Future
3052** versions of SQLite may change the behavior of sqlite3_column_type()
3053** following a type conversion.
3054**
drhd68eee02009-12-11 03:44:18 +00003055** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
drh6ed48bf2007-06-14 20:57:18 +00003056** routine returns the number of bytes in that BLOB or string.
drhd68eee02009-12-11 03:44:18 +00003057** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
drh6ed48bf2007-06-14 20:57:18 +00003058** the string to UTF-8 and then returns the number of bytes.
drhd68eee02009-12-11 03:44:18 +00003059** ^If the result is a numeric value then sqlite3_column_bytes() uses
mihailimebe796c2008-06-21 20:11:17 +00003060** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
drh6ed48bf2007-06-14 20:57:18 +00003061** the number of bytes in that string.
drhd68eee02009-12-11 03:44:18 +00003062** ^The value returned does not include the zero terminator at the end
3063** of the string. ^For clarity: the value returned is the number of
drh6ed48bf2007-06-14 20:57:18 +00003064** bytes in the string, not the number of characters.
3065**
drhd68eee02009-12-11 03:44:18 +00003066** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
3067** even empty strings, are always zero terminated. ^The return
mihailim04bcc002008-06-22 10:21:27 +00003068** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary
drhc0b3abb2007-09-04 12:18:41 +00003069** pointer, possibly even a NULL pointer.
3070**
drhd68eee02009-12-11 03:44:18 +00003071** ^The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
mihailim1c492652008-06-21 18:02:16 +00003072** but leaves the result in UTF-16 in native byte order instead of UTF-8.
drhd68eee02009-12-11 03:44:18 +00003073** ^The zero terminator is not included in this count.
drh4f26d6c2004-05-26 23:25:30 +00003074**
drhd68eee02009-12-11 03:44:18 +00003075** ^The object returned by [sqlite3_column_value()] is an
drhaa28e142008-03-18 13:47:20 +00003076** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
3077** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
3078** If the [unprotected sqlite3_value] object returned by
3079** [sqlite3_column_value()] is used in any other way, including calls
mihailim1c492652008-06-21 18:02:16 +00003080** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
3081** or [sqlite3_value_bytes()], then the behavior is undefined.
drhaa28e142008-03-18 13:47:20 +00003082**
drhd68eee02009-12-11 03:44:18 +00003083** These routines attempt to convert the value where appropriate. ^For
drh4f26d6c2004-05-26 23:25:30 +00003084** example, if the internal representation is FLOAT and a text result
mihailim1c492652008-06-21 18:02:16 +00003085** is requested, [sqlite3_snprintf()] is used internally to perform the
drhd68eee02009-12-11 03:44:18 +00003086** conversion automatically. ^(The following table details the conversions
mihailim1c492652008-06-21 18:02:16 +00003087** that are applied:
drh4f26d6c2004-05-26 23:25:30 +00003088**
drh6ed48bf2007-06-14 20:57:18 +00003089** <blockquote>
3090** <table border="1">
drh8bacf972007-08-25 16:21:29 +00003091** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
drh4f26d6c2004-05-26 23:25:30 +00003092**
drh6ed48bf2007-06-14 20:57:18 +00003093** <tr><td> NULL <td> INTEGER <td> Result is 0
3094** <tr><td> NULL <td> FLOAT <td> Result is 0.0
3095** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
3096** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
3097** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
3098** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
mihailim1c492652008-06-21 18:02:16 +00003099** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
drh6ed48bf2007-06-14 20:57:18 +00003100** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
3101** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
3102** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
3103** <tr><td> TEXT <td> INTEGER <td> Use atoi()
3104** <tr><td> TEXT <td> FLOAT <td> Use atof()
3105** <tr><td> TEXT <td> BLOB <td> No change
3106** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
3107** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
3108** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
3109** </table>
drhd68eee02009-12-11 03:44:18 +00003110** </blockquote>)^
drh4f26d6c2004-05-26 23:25:30 +00003111**
drh6ed48bf2007-06-14 20:57:18 +00003112** The table above makes reference to standard C library functions atoi()
3113** and atof(). SQLite does not really use these functions. It has its
shane26b34032008-05-23 17:21:09 +00003114** own equivalent internal routines. The atoi() and atof() names are
drh6ed48bf2007-06-14 20:57:18 +00003115** used in the table for brevity and because they are familiar to most
3116** C programmers.
3117**
drhd68eee02009-12-11 03:44:18 +00003118** ^Note that when type conversions occur, pointers returned by prior
drh6ed48bf2007-06-14 20:57:18 +00003119** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
mihailim1c492652008-06-21 18:02:16 +00003120** sqlite3_column_text16() may be invalidated.
drhd68eee02009-12-11 03:44:18 +00003121** ^(Type conversions and pointer invalidations might occur
drh6ed48bf2007-06-14 20:57:18 +00003122** in the following cases:
3123**
3124** <ul>
mihailim1c492652008-06-21 18:02:16 +00003125** <li> The initial content is a BLOB and sqlite3_column_text() or
3126** sqlite3_column_text16() is called. A zero-terminator might
3127** need to be added to the string.</li>
3128** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
3129** sqlite3_column_text16() is called. The content must be converted
3130** to UTF-16.</li>
3131** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
3132** sqlite3_column_text() is called. The content must be converted
3133** to UTF-8.</li>
drhd68eee02009-12-11 03:44:18 +00003134** </ul>)^
drh6ed48bf2007-06-14 20:57:18 +00003135**
drhd68eee02009-12-11 03:44:18 +00003136** ^Conversions between UTF-16be and UTF-16le are always done in place and do
drh6ed48bf2007-06-14 20:57:18 +00003137** not invalidate a prior pointer, though of course the content of the buffer
3138** that the prior pointer points to will have been modified. Other kinds
mihailim1c492652008-06-21 18:02:16 +00003139** of conversion are done in place when it is possible, but sometimes they
3140** are not possible and in those cases prior pointers are invalidated.
drh6ed48bf2007-06-14 20:57:18 +00003141**
drhd68eee02009-12-11 03:44:18 +00003142** ^(The safest and easiest to remember policy is to invoke these routines
drh6ed48bf2007-06-14 20:57:18 +00003143** in one of the following ways:
3144**
mihailim1c492652008-06-21 18:02:16 +00003145** <ul>
drh6ed48bf2007-06-14 20:57:18 +00003146** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
3147** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
3148** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
drhd68eee02009-12-11 03:44:18 +00003149** </ul>)^
drh6ed48bf2007-06-14 20:57:18 +00003150**
mihailim1c492652008-06-21 18:02:16 +00003151** In other words, you should call sqlite3_column_text(),
3152** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
3153** into the desired format, then invoke sqlite3_column_bytes() or
3154** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
3155** to sqlite3_column_text() or sqlite3_column_blob() with calls to
3156** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
3157** with calls to sqlite3_column_bytes().
drh32bc3f62007-08-21 20:25:39 +00003158**
drhd68eee02009-12-11 03:44:18 +00003159** ^The pointers returned are valid until a type conversion occurs as
drh32bc3f62007-08-21 20:25:39 +00003160** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
drhd68eee02009-12-11 03:44:18 +00003161** [sqlite3_finalize()] is called. ^The memory space used to hold strings
mihailim04bcc002008-06-22 10:21:27 +00003162** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
mihailim1c492652008-06-21 18:02:16 +00003163** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
drh32bc3f62007-08-21 20:25:39 +00003164** [sqlite3_free()].
drh4a50aac2007-08-23 02:47:53 +00003165**
drhd68eee02009-12-11 03:44:18 +00003166** ^(If a memory allocation error occurs during the evaluation of any
drh4a50aac2007-08-23 02:47:53 +00003167** of these routines, a default value is returned. The default value
3168** is either the integer 0, the floating point number 0.0, or a NULL
3169** pointer. Subsequent calls to [sqlite3_errcode()] will return
drhd68eee02009-12-11 03:44:18 +00003170** [SQLITE_NOMEM].)^
danielk1977106bb232004-05-21 10:08:53 +00003171*/
drhf4479502004-05-27 03:12:53 +00003172const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
3173int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
3174int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
3175double sqlite3_column_double(sqlite3_stmt*, int iCol);
3176int sqlite3_column_int(sqlite3_stmt*, int iCol);
drh6d2069d2007-08-14 01:58:53 +00003177sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
drhf4479502004-05-27 03:12:53 +00003178const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
3179const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
drh4f26d6c2004-05-26 23:25:30 +00003180int sqlite3_column_type(sqlite3_stmt*, int iCol);
drh4be8b512006-06-13 23:51:34 +00003181sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
danielk19774adee202004-05-08 08:23:19 +00003182
danielk197765904932004-05-26 06:18:37 +00003183/*
drhd68eee02009-12-11 03:44:18 +00003184** CAPI3REF: Destroy A Prepared Statement Object
drh6ed48bf2007-06-14 20:57:18 +00003185**
drhd68eee02009-12-11 03:44:18 +00003186** ^The sqlite3_finalize() function is called to delete a [prepared statement].
3187** ^If the statement was executed successfully or not executed at all, then
3188** SQLITE_OK is returned. ^If execution of the statement failed then an
mihailimebe796c2008-06-21 20:11:17 +00003189** [error code] or [extended error code] is returned.
danielk197765904932004-05-26 06:18:37 +00003190**
drhd68eee02009-12-11 03:44:18 +00003191** ^This routine can be called at any point during the execution of the
3192** [prepared statement]. ^If the virtual machine has not
drh6ed48bf2007-06-14 20:57:18 +00003193** completed execution when this routine is called, that is like
mihailimebe796c2008-06-21 20:11:17 +00003194** encountering an error or an [sqlite3_interrupt | interrupt].
drhd68eee02009-12-11 03:44:18 +00003195** ^Incomplete updates may be rolled back and transactions canceled,
mihailimebe796c2008-06-21 20:11:17 +00003196** depending on the circumstances, and the
drh33c1be32008-01-30 16:16:14 +00003197** [error code] returned will be [SQLITE_ABORT].
danielk197765904932004-05-26 06:18:37 +00003198*/
3199int sqlite3_finalize(sqlite3_stmt *pStmt);
3200
3201/*
drhd68eee02009-12-11 03:44:18 +00003202** CAPI3REF: Reset A Prepared Statement Object
drh6ed48bf2007-06-14 20:57:18 +00003203**
mihailimebe796c2008-06-21 20:11:17 +00003204** The sqlite3_reset() function is called to reset a [prepared statement]
3205** object back to its initial state, ready to be re-executed.
drhd68eee02009-12-11 03:44:18 +00003206** ^Any SQL statement variables that had values bound to them using
drh6ed48bf2007-06-14 20:57:18 +00003207** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
3208** Use [sqlite3_clear_bindings()] to reset the bindings.
drh33c1be32008-01-30 16:16:14 +00003209**
drhd68eee02009-12-11 03:44:18 +00003210** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
3211** back to the beginning of its program.
drh33c1be32008-01-30 16:16:14 +00003212**
drhd68eee02009-12-11 03:44:18 +00003213** ^If the most recent call to [sqlite3_step(S)] for the
3214** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
3215** or if [sqlite3_step(S)] has never before been called on S,
3216** then [sqlite3_reset(S)] returns [SQLITE_OK].
drh33c1be32008-01-30 16:16:14 +00003217**
drhd68eee02009-12-11 03:44:18 +00003218** ^If the most recent call to [sqlite3_step(S)] for the
3219** [prepared statement] S indicated an error, then
3220** [sqlite3_reset(S)] returns an appropriate [error code].
drh33c1be32008-01-30 16:16:14 +00003221**
drhd68eee02009-12-11 03:44:18 +00003222** ^The [sqlite3_reset(S)] interface does not change the values
3223** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
danielk197765904932004-05-26 06:18:37 +00003224*/
3225int sqlite3_reset(sqlite3_stmt *pStmt);
3226
3227/*
drhd68eee02009-12-11 03:44:18 +00003228** CAPI3REF: Create Or Redefine SQL Functions
mihailimefc8e8a2008-06-21 16:47:09 +00003229** KEYWORDS: {function creation routines}
3230** KEYWORDS: {application-defined SQL function}
3231** KEYWORDS: {application-defined SQL functions}
drh6ed48bf2007-06-14 20:57:18 +00003232**
drhd68eee02009-12-11 03:44:18 +00003233** ^These two functions (collectively known as "function creation routines")
mihailimebe796c2008-06-21 20:11:17 +00003234** are used to add SQL functions or aggregates or to redefine the behavior
3235** of existing SQL functions or aggregates. The only difference between the
3236** two is that the second parameter, the name of the (scalar) function or
3237** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16
3238** for sqlite3_create_function16().
danielk197765904932004-05-26 06:18:37 +00003239**
drhdf6473a2009-12-13 22:20:08 +00003240** ^The first parameter is the [database connection] to which the SQL
3241** function is to be added. ^If an application uses more than one database
3242** connection then application-defined SQL functions must be added
3243** to each database connection separately.
danielk197765904932004-05-26 06:18:37 +00003244**
mihailimebe796c2008-06-21 20:11:17 +00003245** The second parameter is the name of the SQL function to be created or
drhd68eee02009-12-11 03:44:18 +00003246** redefined. ^The length of the name is limited to 255 bytes, exclusive of
mihailimebe796c2008-06-21 20:11:17 +00003247** the zero-terminator. Note that the name length limit is in bytes, not
drhd68eee02009-12-11 03:44:18 +00003248** characters. ^Any attempt to create a function with a longer name
mihailimebe796c2008-06-21 20:11:17 +00003249** will result in [SQLITE_ERROR] being returned.
drh6ed48bf2007-06-14 20:57:18 +00003250**
drhd68eee02009-12-11 03:44:18 +00003251** ^The third parameter (nArg)
drhc8075422008-09-10 13:09:23 +00003252** is the number of arguments that the SQL function or
drhd68eee02009-12-11 03:44:18 +00003253** aggregate takes. ^If this parameter is -1, then the SQL function or
drh97602f82009-05-24 11:07:49 +00003254** aggregate may take any number of arguments between 0 and the limit
3255** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
drh09943b52009-05-24 21:59:27 +00003256** parameter is less than -1 or greater than 127 then the behavior is
3257** undefined.
danielk197765904932004-05-26 06:18:37 +00003258**
mihailimebe796c2008-06-21 20:11:17 +00003259** The fourth parameter, eTextRep, specifies what
drh6ed48bf2007-06-14 20:57:18 +00003260** [SQLITE_UTF8 | text encoding] this SQL function prefers for
3261** its parameters. Any SQL function implementation should be able to work
3262** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
drhd68eee02009-12-11 03:44:18 +00003263** more efficient with one encoding than another. ^An application may
drh6d2069d2007-08-14 01:58:53 +00003264** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
drh6ed48bf2007-06-14 20:57:18 +00003265** times with the same function but with different values of eTextRep.
drhd68eee02009-12-11 03:44:18 +00003266** ^When multiple implementations of the same function are available, SQLite
drh6ed48bf2007-06-14 20:57:18 +00003267** will pick the one that involves the least amount of data conversion.
mihailimebe796c2008-06-21 20:11:17 +00003268** If there is only a single implementation which does not care what text
3269** encoding is used, then the fourth argument should be [SQLITE_ANY].
drh6ed48bf2007-06-14 20:57:18 +00003270**
drhd68eee02009-12-11 03:44:18 +00003271** ^(The fifth parameter is an arbitrary pointer. The implementation of the
3272** function can gain access to this pointer using [sqlite3_user_data()].)^
danielk1977d02eb1f2004-06-06 09:44:03 +00003273**
danielk197765904932004-05-26 06:18:37 +00003274** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
mihailimebe796c2008-06-21 20:11:17 +00003275** pointers to C-language functions that implement the SQL function or
drhd68eee02009-12-11 03:44:18 +00003276** aggregate. ^A scalar SQL function requires an implementation of the xFunc
3277** callback only; NULL pointers should be passed as the xStep and xFinal
3278** parameters. ^An aggregate SQL function requires an implementation of xStep
3279** and xFinal and NULL should be passed for xFunc. ^To delete an existing
mihailimebe796c2008-06-21 20:11:17 +00003280** SQL function or aggregate, pass NULL for all three function callbacks.
drh6ed48bf2007-06-14 20:57:18 +00003281**
drhd68eee02009-12-11 03:44:18 +00003282** ^It is permitted to register multiple implementations of the same
drh6ed48bf2007-06-14 20:57:18 +00003283** functions with the same name but with either differing numbers of
drhd68eee02009-12-11 03:44:18 +00003284** arguments or differing preferred text encodings. ^SQLite will use
drh6aa5f152009-08-19 15:57:07 +00003285** the implementation that most closely matches the way in which the
drhd68eee02009-12-11 03:44:18 +00003286** SQL function is used. ^A function implementation with a non-negative
drhc8075422008-09-10 13:09:23 +00003287** nArg parameter is a better match than a function implementation with
drhd68eee02009-12-11 03:44:18 +00003288** a negative nArg. ^A function where the preferred text encoding
drhc8075422008-09-10 13:09:23 +00003289** matches the database encoding is a better
3290** match than a function where the encoding is different.
drhd68eee02009-12-11 03:44:18 +00003291** ^A function where the encoding difference is between UTF16le and UTF16be
drhc8075422008-09-10 13:09:23 +00003292** is a closer match than a function where the encoding difference is
3293** between UTF8 and UTF16.
3294**
drhd68eee02009-12-11 03:44:18 +00003295** ^Built-in functions may be overloaded by new application-defined functions.
3296** ^The first application-defined function with a given name overrides all
drhc8075422008-09-10 13:09:23 +00003297** built-in functions in the same [database connection] with the same name.
drhd68eee02009-12-11 03:44:18 +00003298** ^Subsequent application-defined functions of the same name only override
drhc8075422008-09-10 13:09:23 +00003299** prior application-defined functions that are an exact match for the
3300** number of parameters and preferred encoding.
3301**
drhd68eee02009-12-11 03:44:18 +00003302** ^An application-defined function is permitted to call other
drhc8075422008-09-10 13:09:23 +00003303** SQLite interfaces. However, such calls must not
3304** close the database connection nor finalize or reset the prepared
3305** statement in which the function is running.
danielk197765904932004-05-26 06:18:37 +00003306*/
3307int sqlite3_create_function(
drh33c1be32008-01-30 16:16:14 +00003308 sqlite3 *db,
danielk197765904932004-05-26 06:18:37 +00003309 const char *zFunctionName,
3310 int nArg,
3311 int eTextRep,
drh33c1be32008-01-30 16:16:14 +00003312 void *pApp,
danielk197765904932004-05-26 06:18:37 +00003313 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3314 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3315 void (*xFinal)(sqlite3_context*)
3316);
3317int sqlite3_create_function16(
drh33c1be32008-01-30 16:16:14 +00003318 sqlite3 *db,
danielk197765904932004-05-26 06:18:37 +00003319 const void *zFunctionName,
3320 int nArg,
3321 int eTextRep,
drh33c1be32008-01-30 16:16:14 +00003322 void *pApp,
danielk197765904932004-05-26 06:18:37 +00003323 void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
3324 void (*xStep)(sqlite3_context*,int,sqlite3_value**),
3325 void (*xFinal)(sqlite3_context*)
3326);
3327
3328/*
drhd68eee02009-12-11 03:44:18 +00003329** CAPI3REF: Text Encodings
drh6ed48bf2007-06-14 20:57:18 +00003330**
3331** These constant define integer codes that represent the various
3332** text encodings supported by SQLite.
danielk197765904932004-05-26 06:18:37 +00003333*/
drh6ed48bf2007-06-14 20:57:18 +00003334#define SQLITE_UTF8 1
3335#define SQLITE_UTF16LE 2
3336#define SQLITE_UTF16BE 3
3337#define SQLITE_UTF16 4 /* Use native byte order */
3338#define SQLITE_ANY 5 /* sqlite3_create_function only */
3339#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
danielk197765904932004-05-26 06:18:37 +00003340
danielk19770ffba6b2004-05-24 09:10:10 +00003341/*
drhd5a68d32008-08-04 13:44:57 +00003342** CAPI3REF: Deprecated Functions
3343** DEPRECATED
drh6ed48bf2007-06-14 20:57:18 +00003344**
drhd5a68d32008-08-04 13:44:57 +00003345** These functions are [deprecated]. In order to maintain
3346** backwards compatibility with older code, these functions continue
3347** to be supported. However, new applications should avoid
drh6ed48bf2007-06-14 20:57:18 +00003348** the use of these functions. To help encourage people to avoid
shane7ba429a2008-11-10 17:08:49 +00003349** using these functions, we are not going to tell you what they do.
drh6ed48bf2007-06-14 20:57:18 +00003350*/
shaneeec556d2008-10-12 00:27:53 +00003351#ifndef SQLITE_OMIT_DEPRECATED
shanea79c3cc2008-08-11 17:27:01 +00003352SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
3353SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
3354SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
3355SQLITE_DEPRECATED int sqlite3_global_recover(void);
3356SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
3357SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
shaneeec556d2008-10-12 00:27:53 +00003358#endif
drh6ed48bf2007-06-14 20:57:18 +00003359
3360/*
drhd68eee02009-12-11 03:44:18 +00003361** CAPI3REF: Obtaining SQL Function Parameter Values
drh6ed48bf2007-06-14 20:57:18 +00003362**
3363** The C-language implementation of SQL functions and aggregates uses
3364** this set of interface routines to access the parameter values on
3365** the function or aggregate.
3366**
3367** The xFunc (for scalar functions) or xStep (for aggregates) parameters
3368** to [sqlite3_create_function()] and [sqlite3_create_function16()]
3369** define callbacks that implement the SQL functions and aggregates.
3370** The 4th parameter to these callbacks is an array of pointers to
drhaa28e142008-03-18 13:47:20 +00003371** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
drh6ed48bf2007-06-14 20:57:18 +00003372** each parameter to the SQL function. These routines are used to
3373** extract values from the [sqlite3_value] objects.
3374**
drhaa28e142008-03-18 13:47:20 +00003375** These routines work only with [protected sqlite3_value] objects.
3376** Any attempt to use these routines on an [unprotected sqlite3_value]
3377** object results in undefined behavior.
3378**
drhd68eee02009-12-11 03:44:18 +00003379** ^These routines work just like the corresponding [column access functions]
mihailim1c492652008-06-21 18:02:16 +00003380** except that these routines take a single [protected sqlite3_value] object
3381** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
drh6ed48bf2007-06-14 20:57:18 +00003382**
drhd68eee02009-12-11 03:44:18 +00003383** ^The sqlite3_value_text16() interface extracts a UTF-16 string
3384** in the native byte-order of the host machine. ^The
drh6ed48bf2007-06-14 20:57:18 +00003385** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
mihailimebe796c2008-06-21 20:11:17 +00003386** extract UTF-16 strings as big-endian and little-endian respectively.
drh6ed48bf2007-06-14 20:57:18 +00003387**
drhd68eee02009-12-11 03:44:18 +00003388** ^(The sqlite3_value_numeric_type() interface attempts to apply
drh6ed48bf2007-06-14 20:57:18 +00003389** numeric affinity to the value. This means that an attempt is
3390** made to convert the value to an integer or floating point. If
drhf5befa02007-12-06 02:42:07 +00003391** such a conversion is possible without loss of information (in other
mihailimebe796c2008-06-21 20:11:17 +00003392** words, if the value is a string that looks like a number)
3393** then the conversion is performed. Otherwise no conversion occurs.
drhd68eee02009-12-11 03:44:18 +00003394** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
drh6ed48bf2007-06-14 20:57:18 +00003395**
mihailimebe796c2008-06-21 20:11:17 +00003396** Please pay particular attention to the fact that the pointer returned
3397** from [sqlite3_value_blob()], [sqlite3_value_text()], or
drh6ed48bf2007-06-14 20:57:18 +00003398** [sqlite3_value_text16()] can be invalidated by a subsequent call to
drh6d2069d2007-08-14 01:58:53 +00003399** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
mihailimebe796c2008-06-21 20:11:17 +00003400** or [sqlite3_value_text16()].
drhe53831d2007-08-17 01:14:38 +00003401**
3402** These routines must be called from the same thread as
drhaa28e142008-03-18 13:47:20 +00003403** the SQL function that supplied the [sqlite3_value*] parameters.
danielk19770ffba6b2004-05-24 09:10:10 +00003404*/
drhf4479502004-05-27 03:12:53 +00003405const void *sqlite3_value_blob(sqlite3_value*);
3406int sqlite3_value_bytes(sqlite3_value*);
3407int sqlite3_value_bytes16(sqlite3_value*);
3408double sqlite3_value_double(sqlite3_value*);
3409int sqlite3_value_int(sqlite3_value*);
drh6d2069d2007-08-14 01:58:53 +00003410sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
drhf4479502004-05-27 03:12:53 +00003411const unsigned char *sqlite3_value_text(sqlite3_value*);
3412const void *sqlite3_value_text16(sqlite3_value*);
danielk1977d8123362004-06-12 09:25:12 +00003413const void *sqlite3_value_text16le(sqlite3_value*);
3414const void *sqlite3_value_text16be(sqlite3_value*);
danielk197793d46752004-05-23 13:30:58 +00003415int sqlite3_value_type(sqlite3_value*);
drh29d72102006-02-09 22:13:41 +00003416int sqlite3_value_numeric_type(sqlite3_value*);
danielk19770ffba6b2004-05-24 09:10:10 +00003417
3418/*
drhd68eee02009-12-11 03:44:18 +00003419** CAPI3REF: Obtain Aggregate Function Context
drh6ed48bf2007-06-14 20:57:18 +00003420**
drhd68eee02009-12-11 03:44:18 +00003421** Implementions of aggregate SQL functions use this
3422** routine to allocate memory for storing their state.
mihailimebe796c2008-06-21 20:11:17 +00003423**
drhd68eee02009-12-11 03:44:18 +00003424** ^The first time the sqlite3_aggregate_context(C,N) routine is called
3425** for a particular aggregate function, SQLite
3426** allocates N of memory, zeroes out that memory, and returns a pointer
3427** to the new memory. ^On second and subsequent calls to
3428** sqlite3_aggregate_context() for the same aggregate function instance,
3429** the same buffer is returned. Sqlite3_aggregate_context() is normally
3430** called once for each invocation of the xStep callback and then one
3431** last time when the xFinal callback is invoked. ^(When no rows match
3432** an aggregate query, the xStep() callback of the aggregate function
3433** implementation is never called and xFinal() is called exactly once.
3434** In those cases, sqlite3_aggregate_context() might be called for the
3435** first time from within xFinal().)^
danielk19770ae8b832004-05-25 12:05:56 +00003436**
drhd68eee02009-12-11 03:44:18 +00003437** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
3438** less than or equal to zero or if a memory allocate error occurs.
drh6ed48bf2007-06-14 20:57:18 +00003439**
drhd68eee02009-12-11 03:44:18 +00003440** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
3441** determined by the N parameter on first successful call. Changing the
3442** value of N in subsequent call to sqlite3_aggregate_context() within
3443** the same aggregate function instance will not resize the memory
3444** allocation.)^
3445**
3446** ^SQLite automatically frees the memory allocated by
3447** sqlite3_aggregate_context() when the aggregate query concludes.
3448**
3449** The first parameter must be a copy of the
mihailimebe796c2008-06-21 20:11:17 +00003450** [sqlite3_context | SQL function context] that is the first parameter
drhd68eee02009-12-11 03:44:18 +00003451** to the xStep or xFinal callback routine that implements the aggregate
3452** function.
drhe53831d2007-08-17 01:14:38 +00003453**
3454** This routine must be called from the same thread in which
drh605264d2007-08-21 15:13:19 +00003455** the aggregate SQL function is running.
danielk19770ae8b832004-05-25 12:05:56 +00003456*/
drh4f26d6c2004-05-26 23:25:30 +00003457void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
danielk19777e18c252004-05-25 11:47:24 +00003458
3459/*
drhd68eee02009-12-11 03:44:18 +00003460** CAPI3REF: User Data For Functions
drh6ed48bf2007-06-14 20:57:18 +00003461**
drhd68eee02009-12-11 03:44:18 +00003462** ^The sqlite3_user_data() interface returns a copy of
drhf5befa02007-12-06 02:42:07 +00003463** the pointer that was the pUserData parameter (the 5th parameter)
shane26b34032008-05-23 17:21:09 +00003464** of the [sqlite3_create_function()]
drhf5befa02007-12-06 02:42:07 +00003465** and [sqlite3_create_function16()] routines that originally
drhfa4a4b92008-03-19 21:45:51 +00003466** registered the application defined function.
3467**
drhd68eee02009-12-11 03:44:18 +00003468** This routine must be called from the same thread in which
3469** the application-defined function is running.
3470*/
3471void *sqlite3_user_data(sqlite3_context*);
3472
3473/*
3474** CAPI3REF: Database Connection For Functions
3475**
3476** ^The sqlite3_context_db_handle() interface returns a copy of
3477** the pointer to the [database connection] (the 1st parameter)
3478** of the [sqlite3_create_function()]
3479** and [sqlite3_create_function16()] routines that originally
3480** registered the application defined function.
drhfa4a4b92008-03-19 21:45:51 +00003481*/
3482sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
3483
3484/*
drhd68eee02009-12-11 03:44:18 +00003485** CAPI3REF: Function Auxiliary Data
drh6ed48bf2007-06-14 20:57:18 +00003486**
3487** The following two functions may be used by scalar SQL functions to
mihailimebe796c2008-06-21 20:11:17 +00003488** associate metadata with argument values. If the same value is passed to
drh6ed48bf2007-06-14 20:57:18 +00003489** multiple invocations of the same SQL function during query execution, under
mihailimebe796c2008-06-21 20:11:17 +00003490** some circumstances the associated metadata may be preserved. This may
danielk1977682f68b2004-06-05 10:22:17 +00003491** be used, for example, to add a regular-expression matching scalar
3492** function. The compiled version of the regular expression is stored as
mihailimebe796c2008-06-21 20:11:17 +00003493** metadata associated with the SQL value passed as the regular expression
drh6ed48bf2007-06-14 20:57:18 +00003494** pattern. The compiled regular expression can be reused on multiple
3495** invocations of the same function so that the original pattern string
3496** does not need to be recompiled on each invocation.
danielk1977682f68b2004-06-05 10:22:17 +00003497**
drhd68eee02009-12-11 03:44:18 +00003498** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
drhf5befa02007-12-06 02:42:07 +00003499** associated by the sqlite3_set_auxdata() function with the Nth argument
drhd68eee02009-12-11 03:44:18 +00003500** value to the application-defined function. ^If no metadata has been ever
mihailimebe796c2008-06-21 20:11:17 +00003501** been set for the Nth argument of the function, or if the corresponding
3502** function parameter has changed since the meta-data was set,
3503** then sqlite3_get_auxdata() returns a NULL pointer.
danielk1977682f68b2004-06-05 10:22:17 +00003504**
drhd68eee02009-12-11 03:44:18 +00003505** ^The sqlite3_set_auxdata() interface saves the metadata
mihailimebe796c2008-06-21 20:11:17 +00003506** pointed to by its 3rd parameter as the metadata for the N-th
drhafc91042008-02-21 02:09:45 +00003507** argument of the application-defined function. Subsequent
drhf5befa02007-12-06 02:42:07 +00003508** calls to sqlite3_get_auxdata() might return this data, if it has
mihailimebe796c2008-06-21 20:11:17 +00003509** not been destroyed.
drhd68eee02009-12-11 03:44:18 +00003510** ^If it is not NULL, SQLite will invoke the destructor
drhf5befa02007-12-06 02:42:07 +00003511** function given by the 4th parameter to sqlite3_set_auxdata() on
mihailimebe796c2008-06-21 20:11:17 +00003512** the metadata when the corresponding function parameter changes
drhafc91042008-02-21 02:09:45 +00003513** or when the SQL statement completes, whichever comes first.
3514**
mihailimebe796c2008-06-21 20:11:17 +00003515** SQLite is free to call the destructor and drop metadata on any
drhd68eee02009-12-11 03:44:18 +00003516** parameter of any function at any time. ^The only guarantee is that
mihailimebe796c2008-06-21 20:11:17 +00003517** the destructor will be called before the metadata is dropped.
danielk1977682f68b2004-06-05 10:22:17 +00003518**
drhd68eee02009-12-11 03:44:18 +00003519** ^(In practice, metadata is preserved between function calls for
danielk1977682f68b2004-06-05 10:22:17 +00003520** expressions that are constant at compile time. This includes literal
drhd68eee02009-12-11 03:44:18 +00003521** values and [parameters].)^
drhe53831d2007-08-17 01:14:38 +00003522**
drhb21c8cd2007-08-21 19:33:56 +00003523** These routines must be called from the same thread in which
3524** the SQL function is running.
danielk1977682f68b2004-06-05 10:22:17 +00003525*/
drhf5befa02007-12-06 02:42:07 +00003526void *sqlite3_get_auxdata(sqlite3_context*, int N);
3527void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
danielk1977682f68b2004-06-05 10:22:17 +00003528
drha2854222004-06-17 19:04:17 +00003529
3530/*
drhd68eee02009-12-11 03:44:18 +00003531** CAPI3REF: Constants Defining Special Destructor Behavior
drh6ed48bf2007-06-14 20:57:18 +00003532**
mihailimebe796c2008-06-21 20:11:17 +00003533** These are special values for the destructor that is passed in as the
drhd68eee02009-12-11 03:44:18 +00003534** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
drha2854222004-06-17 19:04:17 +00003535** argument is SQLITE_STATIC, it means that the content pointer is constant
drhd68eee02009-12-11 03:44:18 +00003536** and will never change. It does not need to be destroyed. ^The
drha2854222004-06-17 19:04:17 +00003537** SQLITE_TRANSIENT value means that the content will likely change in
3538** the near future and that SQLite should make its own private copy of
3539** the content before returning.
drh6c9121a2007-01-26 00:51:43 +00003540**
3541** The typedef is necessary to work around problems in certain
3542** C++ compilers. See ticket #2191.
drha2854222004-06-17 19:04:17 +00003543*/
drh6c9121a2007-01-26 00:51:43 +00003544typedef void (*sqlite3_destructor_type)(void*);
3545#define SQLITE_STATIC ((sqlite3_destructor_type)0)
3546#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
danielk1977d8123362004-06-12 09:25:12 +00003547
danielk1977682f68b2004-06-05 10:22:17 +00003548/*
drhd68eee02009-12-11 03:44:18 +00003549** CAPI3REF: Setting The Result Of An SQL Function
drh6ed48bf2007-06-14 20:57:18 +00003550**
3551** These routines are used by the xFunc or xFinal callbacks that
3552** implement SQL functions and aggregates. See
3553** [sqlite3_create_function()] and [sqlite3_create_function16()]
3554** for additional information.
3555**
mihailimebe796c2008-06-21 20:11:17 +00003556** These functions work very much like the [parameter binding] family of
3557** functions used to bind values to host parameters in prepared statements.
3558** Refer to the [SQL parameter] documentation for additional information.
drh6ed48bf2007-06-14 20:57:18 +00003559**
drhd68eee02009-12-11 03:44:18 +00003560** ^The sqlite3_result_blob() interface sets the result from
mihailimebe796c2008-06-21 20:11:17 +00003561** an application-defined function to be the BLOB whose content is pointed
drhf5befa02007-12-06 02:42:07 +00003562** to by the second parameter and which is N bytes long where N is the
mihailimebe796c2008-06-21 20:11:17 +00003563** third parameter.
3564**
drhd68eee02009-12-11 03:44:18 +00003565** ^The sqlite3_result_zeroblob() interfaces set the result of
mihailimebe796c2008-06-21 20:11:17 +00003566** the application-defined function to be a BLOB containing all zero
drhf5befa02007-12-06 02:42:07 +00003567** bytes and N bytes in size, where N is the value of the 2nd parameter.
drh6ed48bf2007-06-14 20:57:18 +00003568**
drhd68eee02009-12-11 03:44:18 +00003569** ^The sqlite3_result_double() interface sets the result from
mihailimebe796c2008-06-21 20:11:17 +00003570** an application-defined function to be a floating point value specified
drhf5befa02007-12-06 02:42:07 +00003571** by its 2nd argument.
drhe53831d2007-08-17 01:14:38 +00003572**
drhd68eee02009-12-11 03:44:18 +00003573** ^The sqlite3_result_error() and sqlite3_result_error16() functions
drhf5befa02007-12-06 02:42:07 +00003574** cause the implemented SQL function to throw an exception.
drhd68eee02009-12-11 03:44:18 +00003575** ^SQLite uses the string pointed to by the
drhf5befa02007-12-06 02:42:07 +00003576** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
drhd68eee02009-12-11 03:44:18 +00003577** as the text of an error message. ^SQLite interprets the error
3578** message string from sqlite3_result_error() as UTF-8. ^SQLite
mihailimebe796c2008-06-21 20:11:17 +00003579** interprets the string from sqlite3_result_error16() as UTF-16 in native
drhd68eee02009-12-11 03:44:18 +00003580** byte order. ^If the third parameter to sqlite3_result_error()
drhf5befa02007-12-06 02:42:07 +00003581** or sqlite3_result_error16() is negative then SQLite takes as the error
3582** message all text up through the first zero character.
drhd68eee02009-12-11 03:44:18 +00003583** ^If the third parameter to sqlite3_result_error() or
drhf5befa02007-12-06 02:42:07 +00003584** sqlite3_result_error16() is non-negative then SQLite takes that many
3585** bytes (not characters) from the 2nd parameter as the error message.
drhd68eee02009-12-11 03:44:18 +00003586** ^The sqlite3_result_error() and sqlite3_result_error16()
mihailimebe796c2008-06-21 20:11:17 +00003587** routines make a private copy of the error message text before
drhafc91042008-02-21 02:09:45 +00003588** they return. Hence, the calling function can deallocate or
drhf5befa02007-12-06 02:42:07 +00003589** modify the text after they return without harm.
drhd68eee02009-12-11 03:44:18 +00003590** ^The sqlite3_result_error_code() function changes the error code
3591** returned by SQLite as a result of an error in a function. ^By default,
3592** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
drh00e087b2008-04-10 17:14:07 +00003593** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
drhf5befa02007-12-06 02:42:07 +00003594**
drhd68eee02009-12-11 03:44:18 +00003595** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
drhdf6473a2009-12-13 22:20:08 +00003596** indicating that a string or BLOB is too long to represent.
mihailimebe796c2008-06-21 20:11:17 +00003597**
drhd68eee02009-12-11 03:44:18 +00003598** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
mihailimebe796c2008-06-21 20:11:17 +00003599** indicating that a memory allocation failed.
drhf5befa02007-12-06 02:42:07 +00003600**
drhd68eee02009-12-11 03:44:18 +00003601** ^The sqlite3_result_int() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003602** of the application-defined function to be the 32-bit signed integer
3603** value given in the 2nd argument.
drhd68eee02009-12-11 03:44:18 +00003604** ^The sqlite3_result_int64() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003605** of the application-defined function to be the 64-bit signed integer
3606** value given in the 2nd argument.
3607**
drhd68eee02009-12-11 03:44:18 +00003608** ^The sqlite3_result_null() interface sets the return value
drhf5befa02007-12-06 02:42:07 +00003609** of the application-defined function to be NULL.
3610**
drhd68eee02009-12-11 03:44:18 +00003611** ^The sqlite3_result_text(), sqlite3_result_text16(),
drhf5befa02007-12-06 02:42:07 +00003612** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
3613** set the return value of the application-defined function to be
3614** a text string which is represented as UTF-8, UTF-16 native byte order,
3615** UTF-16 little endian, or UTF-16 big endian, respectively.
drhd68eee02009-12-11 03:44:18 +00003616** ^SQLite takes the text result from the application from
drhf5befa02007-12-06 02:42:07 +00003617** the 2nd parameter of the sqlite3_result_text* interfaces.
drhd68eee02009-12-11 03:44:18 +00003618** ^If the 3rd parameter to the sqlite3_result_text* interfaces
mihailimebe796c2008-06-21 20:11:17 +00003619** is negative, then SQLite takes result text from the 2nd parameter
drhf5befa02007-12-06 02:42:07 +00003620** through the first zero character.
drhd68eee02009-12-11 03:44:18 +00003621** ^If the 3rd parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003622** is non-negative, then as many bytes (not characters) of the text
3623** pointed to by the 2nd parameter are taken as the application-defined
3624** function result.
drhd68eee02009-12-11 03:44:18 +00003625** ^If the 4th parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003626** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
mihailimebe796c2008-06-21 20:11:17 +00003627** function as the destructor on the text or BLOB result when it has
drhf5befa02007-12-06 02:42:07 +00003628** finished using that result.
drhd68eee02009-12-11 03:44:18 +00003629** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
mihailimebe796c2008-06-21 20:11:17 +00003630** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
3631** assumes that the text or BLOB result is in constant space and does not
drh9e42f8a2009-08-13 20:15:29 +00003632** copy the content of the parameter nor call a destructor on the content
3633** when it has finished using that result.
drhd68eee02009-12-11 03:44:18 +00003634** ^If the 4th parameter to the sqlite3_result_text* interfaces
drhf5befa02007-12-06 02:42:07 +00003635** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
3636** then SQLite makes a copy of the result into space obtained from
3637** from [sqlite3_malloc()] before it returns.
3638**
drhd68eee02009-12-11 03:44:18 +00003639** ^The sqlite3_result_value() interface sets the result of
drhaa28e142008-03-18 13:47:20 +00003640** the application-defined function to be a copy the
drhd68eee02009-12-11 03:44:18 +00003641** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
drhf5befa02007-12-06 02:42:07 +00003642** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
mihailimebe796c2008-06-21 20:11:17 +00003643** so that the [sqlite3_value] specified in the parameter may change or
drhf5befa02007-12-06 02:42:07 +00003644** be deallocated after sqlite3_result_value() returns without harm.
drhd68eee02009-12-11 03:44:18 +00003645** ^A [protected sqlite3_value] object may always be used where an
drhaa28e142008-03-18 13:47:20 +00003646** [unprotected sqlite3_value] object is required, so either
3647** kind of [sqlite3_value] object can be used with this interface.
drhf5befa02007-12-06 02:42:07 +00003648**
mihailimebe796c2008-06-21 20:11:17 +00003649** If these routines are called from within the different thread
shane26b34032008-05-23 17:21:09 +00003650** than the one containing the application-defined function that received
drhf5befa02007-12-06 02:42:07 +00003651** the [sqlite3_context] pointer, the results are undefined.
danielk19777e18c252004-05-25 11:47:24 +00003652*/
danielk1977d8123362004-06-12 09:25:12 +00003653void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
drh4f26d6c2004-05-26 23:25:30 +00003654void sqlite3_result_double(sqlite3_context*, double);
danielk19777e18c252004-05-25 11:47:24 +00003655void sqlite3_result_error(sqlite3_context*, const char*, int);
3656void sqlite3_result_error16(sqlite3_context*, const void*, int);
drh6ed48bf2007-06-14 20:57:18 +00003657void sqlite3_result_error_toobig(sqlite3_context*);
danielk1977a1644fd2007-08-29 12:31:25 +00003658void sqlite3_result_error_nomem(sqlite3_context*);
drh69544ec2008-02-06 14:11:34 +00003659void sqlite3_result_error_code(sqlite3_context*, int);
drh4f26d6c2004-05-26 23:25:30 +00003660void sqlite3_result_int(sqlite3_context*, int);
drh6d2069d2007-08-14 01:58:53 +00003661void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
drh4f26d6c2004-05-26 23:25:30 +00003662void sqlite3_result_null(sqlite3_context*);
danielk1977d8123362004-06-12 09:25:12 +00003663void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
3664void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
3665void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
3666void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
drh4f26d6c2004-05-26 23:25:30 +00003667void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
drhb026e052007-05-02 01:34:31 +00003668void sqlite3_result_zeroblob(sqlite3_context*, int n);
drhf9b596e2004-05-26 16:54:42 +00003669
drh52619df2004-06-11 17:48:02 +00003670/*
drhd68eee02009-12-11 03:44:18 +00003671** CAPI3REF: Define New Collating Sequences
drh6ed48bf2007-06-14 20:57:18 +00003672**
3673** These functions are used to add new collation sequences to the
mihailimebe796c2008-06-21 20:11:17 +00003674** [database connection] specified as the first argument.
danielk19777cedc8d2004-06-10 10:50:08 +00003675**
drhd68eee02009-12-11 03:44:18 +00003676** ^The name of the new collation sequence is specified as a UTF-8 string
drh6ed48bf2007-06-14 20:57:18 +00003677** for sqlite3_create_collation() and sqlite3_create_collation_v2()
drhd68eee02009-12-11 03:44:18 +00003678** and a UTF-16 string for sqlite3_create_collation16(). ^In all cases
drh6ed48bf2007-06-14 20:57:18 +00003679** the name is passed as the second function argument.
danielk19777cedc8d2004-06-10 10:50:08 +00003680**
drhd68eee02009-12-11 03:44:18 +00003681** ^The third argument may be one of the constants [SQLITE_UTF8],
drh51c7d862009-04-27 18:46:06 +00003682** [SQLITE_UTF16LE], or [SQLITE_UTF16BE], indicating that the user-supplied
danielk19777cedc8d2004-06-10 10:50:08 +00003683** routine expects to be passed pointers to strings encoded using UTF-8,
drhd68eee02009-12-11 03:44:18 +00003684** UTF-16 little-endian, or UTF-16 big-endian, respectively. ^The
drh51c7d862009-04-27 18:46:06 +00003685** third argument might also be [SQLITE_UTF16] to indicate that the routine
3686** expects pointers to be UTF-16 strings in the native byte order, or the
3687** argument can be [SQLITE_UTF16_ALIGNED] if the
drh4145f832007-10-12 18:30:12 +00003688** the routine expects pointers to 16-bit word aligned strings
drh51c7d862009-04-27 18:46:06 +00003689** of UTF-16 in the native byte order.
danielk19777cedc8d2004-06-10 10:50:08 +00003690**
3691** A pointer to the user supplied routine must be passed as the fifth
drhd68eee02009-12-11 03:44:18 +00003692** argument. ^If it is NULL, this is the same as deleting the collation
drhf5befa02007-12-06 02:42:07 +00003693** sequence (so that SQLite cannot call it anymore).
drhd68eee02009-12-11 03:44:18 +00003694** ^Each time the application supplied function is invoked, it is passed
mihailimebe796c2008-06-21 20:11:17 +00003695** as its first parameter a copy of the void* passed as the fourth argument
3696** to sqlite3_create_collation() or sqlite3_create_collation16().
danielk19777cedc8d2004-06-10 10:50:08 +00003697**
drhd68eee02009-12-11 03:44:18 +00003698** ^The remaining arguments to the application-supplied routine are two strings,
drh33c1be32008-01-30 16:16:14 +00003699** each represented by a (length, data) pair and encoded in the encoding
danielk19777cedc8d2004-06-10 10:50:08 +00003700** that was passed as the third argument when the collation sequence was
drhfb434032009-12-11 23:11:26 +00003701** registered. The application defined collation routine should
mihailimebe796c2008-06-21 20:11:17 +00003702** return negative, zero or positive if the first string is less than,
3703** equal to, or greater than the second string. i.e. (STRING1 - STRING2).
drh6ed48bf2007-06-14 20:57:18 +00003704**
drhd68eee02009-12-11 03:44:18 +00003705** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
shane26b34032008-05-23 17:21:09 +00003706** except that it takes an extra argument which is a destructor for
drhd68eee02009-12-11 03:44:18 +00003707** the collation. ^The destructor is called when the collation is
drh6ed48bf2007-06-14 20:57:18 +00003708** destroyed and is passed a copy of the fourth parameter void* pointer
drhf5befa02007-12-06 02:42:07 +00003709** of the sqlite3_create_collation_v2().
drhd68eee02009-12-11 03:44:18 +00003710** ^Collations are destroyed when they are overridden by later calls to the
mihailimebe796c2008-06-21 20:11:17 +00003711** collation creation functions or when the [database connection] is closed
3712** using [sqlite3_close()].
drhafc91042008-02-21 02:09:45 +00003713**
drh51c7d862009-04-27 18:46:06 +00003714** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
danielk19777cedc8d2004-06-10 10:50:08 +00003715*/
danielk19770202b292004-06-09 09:55:16 +00003716int sqlite3_create_collation(
3717 sqlite3*,
3718 const char *zName,
danielk19777cedc8d2004-06-10 10:50:08 +00003719 int eTextRep,
danielk19770202b292004-06-09 09:55:16 +00003720 void*,
3721 int(*xCompare)(void*,int,const void*,int,const void*)
3722);
drh6ed48bf2007-06-14 20:57:18 +00003723int sqlite3_create_collation_v2(
3724 sqlite3*,
3725 const char *zName,
3726 int eTextRep,
3727 void*,
3728 int(*xCompare)(void*,int,const void*,int,const void*),
3729 void(*xDestroy)(void*)
3730);
danielk19770202b292004-06-09 09:55:16 +00003731int sqlite3_create_collation16(
3732 sqlite3*,
mihailimbda2e622008-06-23 11:23:14 +00003733 const void *zName,
danielk19777cedc8d2004-06-10 10:50:08 +00003734 int eTextRep,
danielk19770202b292004-06-09 09:55:16 +00003735 void*,
3736 int(*xCompare)(void*,int,const void*,int,const void*)
3737);
3738
danielk19777cedc8d2004-06-10 10:50:08 +00003739/*
drhfb434032009-12-11 23:11:26 +00003740** CAPI3REF: Collation Needed Callbacks
danielk1977a393c032007-05-07 14:58:53 +00003741**
drhd68eee02009-12-11 03:44:18 +00003742** ^To avoid having to register all collation sequences before a database
danielk19777cedc8d2004-06-10 10:50:08 +00003743** can be used, a single callback function may be registered with the
drh9be37f62009-12-12 23:57:36 +00003744** [database connection] to be invoked whenever an undefined collation
mihailimdc884822008-06-22 08:58:50 +00003745** sequence is required.
danielk19777cedc8d2004-06-10 10:50:08 +00003746**
drhd68eee02009-12-11 03:44:18 +00003747** ^If the function is registered using the sqlite3_collation_needed() API,
danielk19777cedc8d2004-06-10 10:50:08 +00003748** then it is passed the names of undefined collation sequences as strings
drhd68eee02009-12-11 03:44:18 +00003749** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
mihailimdc884822008-06-22 08:58:50 +00003750** the names are passed as UTF-16 in machine native byte order.
drh9be37f62009-12-12 23:57:36 +00003751** ^A call to either function replaces the existing collation-needed callback.
danielk19777cedc8d2004-06-10 10:50:08 +00003752**
drhd68eee02009-12-11 03:44:18 +00003753** ^(When the callback is invoked, the first argument passed is a copy
danielk19777cedc8d2004-06-10 10:50:08 +00003754** of the second argument to sqlite3_collation_needed() or
drhafc91042008-02-21 02:09:45 +00003755** sqlite3_collation_needed16(). The second argument is the database
mihailimdc884822008-06-22 08:58:50 +00003756** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
3757** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
3758** sequence function required. The fourth parameter is the name of the
drhd68eee02009-12-11 03:44:18 +00003759** required collation sequence.)^
danielk19777cedc8d2004-06-10 10:50:08 +00003760**
drh6ed48bf2007-06-14 20:57:18 +00003761** The callback function should register the desired collation using
3762** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
3763** [sqlite3_create_collation_v2()].
danielk19777cedc8d2004-06-10 10:50:08 +00003764*/
3765int sqlite3_collation_needed(
3766 sqlite3*,
3767 void*,
3768 void(*)(void*,sqlite3*,int eTextRep,const char*)
3769);
3770int sqlite3_collation_needed16(
3771 sqlite3*,
3772 void*,
3773 void(*)(void*,sqlite3*,int eTextRep,const void*)
3774);
3775
drhd4542142010-03-30 11:57:01 +00003776#ifdef SQLITE_HAS_CODEC
drh2011d5f2004-07-22 02:40:37 +00003777/*
3778** Specify the key for an encrypted database. This routine should be
3779** called right after sqlite3_open().
3780**
3781** The code to implement this API is not available in the public release
3782** of SQLite.
3783*/
3784int sqlite3_key(
3785 sqlite3 *db, /* Database to be rekeyed */
3786 const void *pKey, int nKey /* The key */
3787);
3788
3789/*
3790** Change the key on an open database. If the current database is not
3791** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
3792** database is decrypted.
3793**
3794** The code to implement this API is not available in the public release
3795** of SQLite.
3796*/
3797int sqlite3_rekey(
3798 sqlite3 *db, /* Database to be rekeyed */
3799 const void *pKey, int nKey /* The new key */
3800);
danielk19770202b292004-06-09 09:55:16 +00003801
drhab3f9fe2004-08-14 17:10:10 +00003802/*
shaneh959dda62010-01-28 19:56:27 +00003803** Specify the activation key for a SEE database. Unless
3804** activated, none of the SEE routines will work.
3805*/
drha7564662010-02-22 19:32:31 +00003806void sqlite3_activate_see(
3807 const char *zPassPhrase /* Activation phrase */
3808);
3809#endif
3810
3811#ifdef SQLITE_ENABLE_CEROD
shaneh959dda62010-01-28 19:56:27 +00003812/*
3813** Specify the activation key for a CEROD database. Unless
3814** activated, none of the CEROD routines will work.
3815*/
drha7564662010-02-22 19:32:31 +00003816void sqlite3_activate_cerod(
3817 const char *zPassPhrase /* Activation phrase */
3818);
shaneh959dda62010-01-28 19:56:27 +00003819#endif
3820
3821/*
drhd68eee02009-12-11 03:44:18 +00003822** CAPI3REF: Suspend Execution For A Short Time
drh6ed48bf2007-06-14 20:57:18 +00003823**
drhd68eee02009-12-11 03:44:18 +00003824** ^The sqlite3_sleep() function causes the current thread to suspend execution
drhfddfa2d2007-12-05 18:05:16 +00003825** for at least a number of milliseconds specified in its parameter.
danielk1977600dd0b2005-01-20 01:14:23 +00003826**
drhd68eee02009-12-11 03:44:18 +00003827** ^If the operating system does not support sleep requests with
mihailimdc884822008-06-22 08:58:50 +00003828** millisecond time resolution, then the time will be rounded up to
drhd68eee02009-12-11 03:44:18 +00003829** the nearest second. ^The number of milliseconds of sleep actually
danielk1977600dd0b2005-01-20 01:14:23 +00003830** requested from the operating system is returned.
drh8bacf972007-08-25 16:21:29 +00003831**
drhd68eee02009-12-11 03:44:18 +00003832** ^SQLite implements this interface by calling the xSleep()
drhafc91042008-02-21 02:09:45 +00003833** method of the default [sqlite3_vfs] object.
danielk1977600dd0b2005-01-20 01:14:23 +00003834*/
3835int sqlite3_sleep(int);
3836
3837/*
drhd68eee02009-12-11 03:44:18 +00003838** CAPI3REF: Name Of The Folder Holding Temporary Files
drhd89bd002005-01-22 03:03:54 +00003839**
drh7a98b852009-12-13 23:03:01 +00003840** ^(If this global variable is made to point to a string which is
shane26b34032008-05-23 17:21:09 +00003841** the name of a folder (a.k.a. directory), then all temporary files
drhd68eee02009-12-11 03:44:18 +00003842** created by SQLite when using a built-in [sqlite3_vfs | VFS]
drh7a98b852009-12-13 23:03:01 +00003843** will be placed in that directory.)^ ^If this variable
mihailimdc884822008-06-22 08:58:50 +00003844** is a NULL pointer, then SQLite performs a search for an appropriate
3845** temporary file directory.
drhab3f9fe2004-08-14 17:10:10 +00003846**
drh1a25f112009-04-06 15:55:03 +00003847** It is not safe to read or modify this variable in more than one
3848** thread at a time. It is not safe to read or modify this variable
3849** if a [database connection] is being used at the same time in a separate
3850** thread.
3851** It is intended that this variable be set once
drh4ff7fa02007-09-01 18:17:21 +00003852** as part of process initialization and before any SQLite interface
drh1a25f112009-04-06 15:55:03 +00003853** routines have been called and that this variable remain unchanged
3854** thereafter.
3855**
drhd68eee02009-12-11 03:44:18 +00003856** ^The [temp_store_directory pragma] may modify this variable and cause
3857** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
drh1a25f112009-04-06 15:55:03 +00003858** the [temp_store_directory pragma] always assumes that any string
3859** that this variable points to is held in memory obtained from
3860** [sqlite3_malloc] and the pragma may attempt to free that memory
3861** using [sqlite3_free].
3862** Hence, if this variable is modified directly, either it should be
3863** made NULL or made to point to memory obtained from [sqlite3_malloc]
3864** or else the use of the [temp_store_directory pragma] should be avoided.
drhab3f9fe2004-08-14 17:10:10 +00003865*/
drh73be5012007-08-08 12:11:21 +00003866SQLITE_EXTERN char *sqlite3_temp_directory;
drhab3f9fe2004-08-14 17:10:10 +00003867
danielk19776b456a22005-03-21 04:04:02 +00003868/*
drhd68eee02009-12-11 03:44:18 +00003869** CAPI3REF: Test For Auto-Commit Mode
mihailim15194222008-06-22 09:55:14 +00003870** KEYWORDS: {autocommit mode}
danielk19776b456a22005-03-21 04:04:02 +00003871**
drhd68eee02009-12-11 03:44:18 +00003872** ^The sqlite3_get_autocommit() interface returns non-zero or
drhf5befa02007-12-06 02:42:07 +00003873** zero if the given database connection is or is not in autocommit mode,
drhd68eee02009-12-11 03:44:18 +00003874** respectively. ^Autocommit mode is on by default.
3875** ^Autocommit mode is disabled by a [BEGIN] statement.
3876** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
drhe30f4422007-08-21 16:15:55 +00003877**
drh7c3472a2007-10-03 20:15:28 +00003878** If certain kinds of errors occur on a statement within a multi-statement
mihailimdc884822008-06-22 08:58:50 +00003879** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
drh7c3472a2007-10-03 20:15:28 +00003880** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
drh33c1be32008-01-30 16:16:14 +00003881** transaction might be rolled back automatically. The only way to
mihailimdc884822008-06-22 08:58:50 +00003882** find out whether SQLite automatically rolled back the transaction after
drh33c1be32008-01-30 16:16:14 +00003883** an error is to use this function.
drh7c3472a2007-10-03 20:15:28 +00003884**
drh8b39db12009-02-18 18:37:58 +00003885** If another thread changes the autocommit status of the database
3886** connection while this routine is running, then the return value
3887** is undefined.
drh3e1d8e62005-05-26 16:23:34 +00003888*/
3889int sqlite3_get_autocommit(sqlite3*);
3890
drh51942bc2005-06-12 22:01:42 +00003891/*
drhd68eee02009-12-11 03:44:18 +00003892** CAPI3REF: Find The Database Handle Of A Prepared Statement
drh6ed48bf2007-06-14 20:57:18 +00003893**
drhd68eee02009-12-11 03:44:18 +00003894** ^The sqlite3_db_handle interface returns the [database connection] handle
3895** to which a [prepared statement] belongs. ^The [database connection]
3896** returned by sqlite3_db_handle is the same [database connection]
3897** that was the first argument
mihailimdc884822008-06-22 08:58:50 +00003898** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
3899** create the statement in the first place.
drh51942bc2005-06-12 22:01:42 +00003900*/
3901sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
drh3e1d8e62005-05-26 16:23:34 +00003902
drhbb5a9c32008-06-19 02:52:25 +00003903/*
drhd68eee02009-12-11 03:44:18 +00003904** CAPI3REF: Find the next prepared statement
drhbb5a9c32008-06-19 02:52:25 +00003905**
drhd68eee02009-12-11 03:44:18 +00003906** ^This interface returns a pointer to the next [prepared statement] after
3907** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
mihailimdc884822008-06-22 08:58:50 +00003908** then this interface returns a pointer to the first prepared statement
drhd68eee02009-12-11 03:44:18 +00003909** associated with the database connection pDb. ^If no prepared statement
mihailimdc884822008-06-22 08:58:50 +00003910** satisfies the conditions of this routine, it returns NULL.
drhbb5a9c32008-06-19 02:52:25 +00003911**
drh8b39db12009-02-18 18:37:58 +00003912** The [database connection] pointer D in a call to
3913** [sqlite3_next_stmt(D,S)] must refer to an open database
3914** connection and in particular must not be a NULL pointer.
drhbb5a9c32008-06-19 02:52:25 +00003915*/
3916sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
3917
drhb37df7b2005-10-13 02:09:49 +00003918/*
drhfb434032009-12-11 23:11:26 +00003919** CAPI3REF: Commit And Rollback Notification Callbacks
drh6ed48bf2007-06-14 20:57:18 +00003920**
drhd68eee02009-12-11 03:44:18 +00003921** ^The sqlite3_commit_hook() interface registers a callback
drhabda6112009-05-14 22:37:47 +00003922** function to be invoked whenever a transaction is [COMMIT | committed].
drhd68eee02009-12-11 03:44:18 +00003923** ^Any callback set by a previous call to sqlite3_commit_hook()
drhf5befa02007-12-06 02:42:07 +00003924** for the same database connection is overridden.
drhd68eee02009-12-11 03:44:18 +00003925** ^The sqlite3_rollback_hook() interface registers a callback
drhabda6112009-05-14 22:37:47 +00003926** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
drhd68eee02009-12-11 03:44:18 +00003927** ^Any callback set by a previous call to sqlite3_rollback_hook()
drhf5befa02007-12-06 02:42:07 +00003928** for the same database connection is overridden.
drhd68eee02009-12-11 03:44:18 +00003929** ^The pArg argument is passed through to the callback.
3930** ^If the callback on a commit hook function returns non-zero,
mihailimdc884822008-06-22 08:58:50 +00003931** then the commit is converted into a rollback.
drh6ed48bf2007-06-14 20:57:18 +00003932**
drhd68eee02009-12-11 03:44:18 +00003933** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
3934** return the P argument from the previous call of the same function
3935** on the same [database connection] D, or NULL for
3936** the first call for each function on D.
drh6ed48bf2007-06-14 20:57:18 +00003937**
drhc8075422008-09-10 13:09:23 +00003938** The callback implementation must not do anything that will modify
3939** the database connection that invoked the callback. Any actions
3940** to modify the database connection must be deferred until after the
3941** completion of the [sqlite3_step()] call that triggered the commit
3942** or rollback hook in the first place.
3943** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
3944** database connections for the meaning of "modify" in this paragraph.
3945**
drhd68eee02009-12-11 03:44:18 +00003946** ^Registering a NULL function disables the callback.
drh6ed48bf2007-06-14 20:57:18 +00003947**
drhd68eee02009-12-11 03:44:18 +00003948** ^When the commit hook callback routine returns zero, the [COMMIT]
3949** operation is allowed to continue normally. ^If the commit hook
drhabda6112009-05-14 22:37:47 +00003950** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
drhd68eee02009-12-11 03:44:18 +00003951** ^The rollback hook is invoked on a rollback that results from a commit
drhabda6112009-05-14 22:37:47 +00003952** hook returning non-zero, just as it would be with any other rollback.
3953**
drhd68eee02009-12-11 03:44:18 +00003954** ^For the purposes of this API, a transaction is said to have been
drh6ed48bf2007-06-14 20:57:18 +00003955** rolled back if an explicit "ROLLBACK" statement is executed, or
drhf5befa02007-12-06 02:42:07 +00003956** an error or constraint causes an implicit rollback to occur.
drhd68eee02009-12-11 03:44:18 +00003957** ^The rollback callback is not invoked if a transaction is
drhf5befa02007-12-06 02:42:07 +00003958** automatically rolled back because the database connection is closed.
drh6ed48bf2007-06-14 20:57:18 +00003959**
drhabda6112009-05-14 22:37:47 +00003960** See also the [sqlite3_update_hook()] interface.
drh6ed48bf2007-06-14 20:57:18 +00003961*/
3962void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
3963void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
3964
3965/*
drhd68eee02009-12-11 03:44:18 +00003966** CAPI3REF: Data Change Notification Callbacks
drh6ed48bf2007-06-14 20:57:18 +00003967**
drhd68eee02009-12-11 03:44:18 +00003968** ^The sqlite3_update_hook() interface registers a callback function
mihailimdc884822008-06-22 08:58:50 +00003969** with the [database connection] identified by the first argument
3970** to be invoked whenever a row is updated, inserted or deleted.
drhd68eee02009-12-11 03:44:18 +00003971** ^Any callback set by a previous call to this function
mihailimdc884822008-06-22 08:58:50 +00003972** for the same database connection is overridden.
danielk197794eb6a12005-12-15 15:22:08 +00003973**
drhd68eee02009-12-11 03:44:18 +00003974** ^The second argument is a pointer to the function to invoke when a
mihailimdc884822008-06-22 08:58:50 +00003975** row is updated, inserted or deleted.
drhd68eee02009-12-11 03:44:18 +00003976** ^The first argument to the callback is a copy of the third argument
mihailimdc884822008-06-22 08:58:50 +00003977** to sqlite3_update_hook().
drhd68eee02009-12-11 03:44:18 +00003978** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
mihailimdc884822008-06-22 08:58:50 +00003979** or [SQLITE_UPDATE], depending on the operation that caused the callback
3980** to be invoked.
drhd68eee02009-12-11 03:44:18 +00003981** ^The third and fourth arguments to the callback contain pointers to the
mihailimdc884822008-06-22 08:58:50 +00003982** database and table name containing the affected row.
drhd68eee02009-12-11 03:44:18 +00003983** ^The final callback parameter is the [rowid] of the row.
3984** ^In the case of an update, this is the [rowid] after the update takes place.
danielk197794eb6a12005-12-15 15:22:08 +00003985**
drhd68eee02009-12-11 03:44:18 +00003986** ^(The update hook is not invoked when internal system tables are
3987** modified (i.e. sqlite_master and sqlite_sequence).)^
danielk197771fd80b2005-12-16 06:54:01 +00003988**
drhd68eee02009-12-11 03:44:18 +00003989** ^In the current implementation, the update hook
drhabda6112009-05-14 22:37:47 +00003990** is not invoked when duplication rows are deleted because of an
drhd68eee02009-12-11 03:44:18 +00003991** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
drhabda6112009-05-14 22:37:47 +00003992** invoked when rows are deleted using the [truncate optimization].
3993** The exceptions defined in this paragraph might change in a future
3994** release of SQLite.
3995**
drhc8075422008-09-10 13:09:23 +00003996** The update hook implementation must not do anything that will modify
3997** the database connection that invoked the update hook. Any actions
3998** to modify the database connection must be deferred until after the
3999** completion of the [sqlite3_step()] call that triggered the update hook.
4000** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
4001** database connections for the meaning of "modify" in this paragraph.
4002**
drhd68eee02009-12-11 03:44:18 +00004003** ^The sqlite3_update_hook(D,C,P) function
4004** returns the P argument from the previous call
4005** on the same [database connection] D, or NULL for
4006** the first call on D.
drhafc91042008-02-21 02:09:45 +00004007**
drhabda6112009-05-14 22:37:47 +00004008** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
4009** interfaces.
danielk197794eb6a12005-12-15 15:22:08 +00004010*/
danielk197771fd80b2005-12-16 06:54:01 +00004011void *sqlite3_update_hook(
danielk197794eb6a12005-12-15 15:22:08 +00004012 sqlite3*,
drh6d2069d2007-08-14 01:58:53 +00004013 void(*)(void *,int ,char const *,char const *,sqlite3_int64),
danielk197794eb6a12005-12-15 15:22:08 +00004014 void*
4015);
danielk197713a68c32005-12-15 10:11:30 +00004016
danielk1977f3f06bb2005-12-16 15:24:28 +00004017/*
drhd68eee02009-12-11 03:44:18 +00004018** CAPI3REF: Enable Or Disable Shared Pager Cache
drhe33b0ed2009-08-06 17:40:45 +00004019** KEYWORDS: {shared cache}
danielk1977f3f06bb2005-12-16 15:24:28 +00004020**
drhd68eee02009-12-11 03:44:18 +00004021** ^(This routine enables or disables the sharing of the database cache
mihailimdc884822008-06-22 08:58:50 +00004022** and schema data structures between [database connection | connections]
4023** to the same database. Sharing is enabled if the argument is true
drhd68eee02009-12-11 03:44:18 +00004024** and disabled if the argument is false.)^
danielk1977f3f06bb2005-12-16 15:24:28 +00004025**
drhd68eee02009-12-11 03:44:18 +00004026** ^Cache sharing is enabled and disabled for an entire process.
mihailimdc884822008-06-22 08:58:50 +00004027** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
4028** sharing was enabled or disabled for each thread separately.
drh6ed48bf2007-06-14 20:57:18 +00004029**
drhd68eee02009-12-11 03:44:18 +00004030** ^(The cache sharing mode set by this interface effects all subsequent
drhe30f4422007-08-21 16:15:55 +00004031** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
drhafc91042008-02-21 02:09:45 +00004032** Existing database connections continue use the sharing mode
drhd68eee02009-12-11 03:44:18 +00004033** that was in effect at the time they were opened.)^
drh6ed48bf2007-06-14 20:57:18 +00004034**
drhd68eee02009-12-11 03:44:18 +00004035** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
4036** successfully. An [error code] is returned otherwise.)^
drh6ed48bf2007-06-14 20:57:18 +00004037**
drhd68eee02009-12-11 03:44:18 +00004038** ^Shared cache is disabled by default. But this might change in
drh4ff7fa02007-09-01 18:17:21 +00004039** future releases of SQLite. Applications that care about shared
4040** cache setting should set it explicitly.
drhafc91042008-02-21 02:09:45 +00004041**
drhaff46972009-02-12 17:07:34 +00004042** See Also: [SQLite Shared-Cache Mode]
danielk1977aef0bf62005-12-30 16:28:01 +00004043*/
4044int sqlite3_enable_shared_cache(int);
4045
4046/*
drhd68eee02009-12-11 03:44:18 +00004047** CAPI3REF: Attempt To Free Heap Memory
drh6ed48bf2007-06-14 20:57:18 +00004048**
drhd68eee02009-12-11 03:44:18 +00004049** ^The sqlite3_release_memory() interface attempts to free N bytes
mihailim04bcc002008-06-22 10:21:27 +00004050** of heap memory by deallocating non-essential memory allocations
drhd68eee02009-12-11 03:44:18 +00004051** held by the database library. Memory used to cache database
mihailim04bcc002008-06-22 10:21:27 +00004052** pages to improve performance is an example of non-essential memory.
drhd68eee02009-12-11 03:44:18 +00004053** ^sqlite3_release_memory() returns the number of bytes actually freed,
mihailim04bcc002008-06-22 10:21:27 +00004054** which might be more or less than the amount requested.
danielk197752622822006-01-09 09:59:49 +00004055*/
4056int sqlite3_release_memory(int);
4057
4058/*
drhd68eee02009-12-11 03:44:18 +00004059** CAPI3REF: Impose A Limit On Heap Size
drh6ed48bf2007-06-14 20:57:18 +00004060**
drhd68eee02009-12-11 03:44:18 +00004061** ^The sqlite3_soft_heap_limit() interface places a "soft" limit
mihailimdc884822008-06-22 08:58:50 +00004062** on the amount of heap memory that may be allocated by SQLite.
drhd68eee02009-12-11 03:44:18 +00004063** ^If an internal allocation is requested that would exceed the
mihailimdc884822008-06-22 08:58:50 +00004064** soft heap limit, [sqlite3_release_memory()] is invoked one or
4065** more times to free up some space before the allocation is performed.
danielk197752622822006-01-09 09:59:49 +00004066**
drhdf6473a2009-12-13 22:20:08 +00004067** ^The limit is called "soft" because if [sqlite3_release_memory()]
mihailimdc884822008-06-22 08:58:50 +00004068** cannot free sufficient memory to prevent the limit from being exceeded,
drhe30f4422007-08-21 16:15:55 +00004069** the memory is allocated anyway and the current operation proceeds.
drh6ed48bf2007-06-14 20:57:18 +00004070**
drhd68eee02009-12-11 03:44:18 +00004071** ^A negative or zero value for N means that there is no soft heap limit and
drhe30f4422007-08-21 16:15:55 +00004072** [sqlite3_release_memory()] will only be called when memory is exhausted.
drhd68eee02009-12-11 03:44:18 +00004073** ^The default value for the soft heap limit is zero.
drh6ed48bf2007-06-14 20:57:18 +00004074**
drhd68eee02009-12-11 03:44:18 +00004075** ^(SQLite makes a best effort to honor the soft heap limit.
shane26b34032008-05-23 17:21:09 +00004076** But if the soft heap limit cannot be honored, execution will
drhd68eee02009-12-11 03:44:18 +00004077** continue without error or notification.)^ This is why the limit is
drh6ed48bf2007-06-14 20:57:18 +00004078** called a "soft" limit. It is advisory only.
4079**
drhe30f4422007-08-21 16:15:55 +00004080** Prior to SQLite version 3.5.0, this routine only constrained the memory
4081** allocated by a single thread - the same thread in which this routine
4082** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
drhafc91042008-02-21 02:09:45 +00004083** applied to all threads. The value specified for the soft heap limit
4084** is an upper bound on the total memory allocation for all threads. In
drh8bacf972007-08-25 16:21:29 +00004085** version 3.5.0 there is no mechanism for limiting the heap usage for
4086** individual threads.
danielk197752622822006-01-09 09:59:49 +00004087*/
drhd2d4a6b2006-01-10 15:18:27 +00004088void sqlite3_soft_heap_limit(int);
danielk197752622822006-01-09 09:59:49 +00004089
4090/*
drhfb434032009-12-11 23:11:26 +00004091** CAPI3REF: Extract Metadata About A Column Of A Table
drh6ed48bf2007-06-14 20:57:18 +00004092**
drhd68eee02009-12-11 03:44:18 +00004093** ^This routine returns metadata about a specific column of a specific
mihailimdc884822008-06-22 08:58:50 +00004094** database table accessible using the [database connection] handle
4095** passed as the first function argument.
danielk1977deb802c2006-02-09 13:43:28 +00004096**
drhd68eee02009-12-11 03:44:18 +00004097** ^The column is identified by the second, third and fourth parameters to
drhdf6473a2009-12-13 22:20:08 +00004098** this function. ^The second parameter is either the name of the database
4099** (i.e. "main", "temp", or an attached database) containing the specified
4100** table or NULL. ^If it is NULL, then all attached databases are searched
mihailimdc884822008-06-22 08:58:50 +00004101** for the table using the same algorithm used by the database engine to
drh7a98b852009-12-13 23:03:01 +00004102** resolve unqualified table references.
danielk1977deb802c2006-02-09 13:43:28 +00004103**
drhd68eee02009-12-11 03:44:18 +00004104** ^The third and fourth parameters to this function are the table and column
mihailimdc884822008-06-22 08:58:50 +00004105** name of the desired column, respectively. Neither of these parameters
danielk1977deb802c2006-02-09 13:43:28 +00004106** may be NULL.
4107**
drhd68eee02009-12-11 03:44:18 +00004108** ^Metadata is returned by writing to the memory locations passed as the 5th
4109** and subsequent parameters to this function. ^Any of these arguments may be
mihailimdc884822008-06-22 08:58:50 +00004110** NULL, in which case the corresponding element of metadata is omitted.
mihailim15194222008-06-22 09:55:14 +00004111**
drhd68eee02009-12-11 03:44:18 +00004112** ^(<blockquote>
mihailimdc884822008-06-22 08:58:50 +00004113** <table border="1">
4114** <tr><th> Parameter <th> Output<br>Type <th> Description
danielk1977deb802c2006-02-09 13:43:28 +00004115**
mihailimdc884822008-06-22 08:58:50 +00004116** <tr><td> 5th <td> const char* <td> Data type
4117** <tr><td> 6th <td> const char* <td> Name of default collation sequence
4118** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
4119** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
drh49c3d572008-12-15 22:51:38 +00004120** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
mihailimdc884822008-06-22 08:58:50 +00004121** </table>
drhd68eee02009-12-11 03:44:18 +00004122** </blockquote>)^
danielk1977deb802c2006-02-09 13:43:28 +00004123**
drhd68eee02009-12-11 03:44:18 +00004124** ^The memory pointed to by the character pointers returned for the
mihailimdc884822008-06-22 08:58:50 +00004125** declaration type and collation sequence is valid only until the next
4126** call to any SQLite API function.
danielk1977deb802c2006-02-09 13:43:28 +00004127**
drhd68eee02009-12-11 03:44:18 +00004128** ^If the specified table is actually a view, an [error code] is returned.
danielk1977deb802c2006-02-09 13:43:28 +00004129**
drhd68eee02009-12-11 03:44:18 +00004130** ^If the specified column is "rowid", "oid" or "_rowid_" and an
drh49c3d572008-12-15 22:51:38 +00004131** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
drhd68eee02009-12-11 03:44:18 +00004132** parameters are set for the explicitly declared column. ^(If there is no
drh49c3d572008-12-15 22:51:38 +00004133** explicitly declared [INTEGER PRIMARY KEY] column, then the output
mihailimdc884822008-06-22 08:58:50 +00004134** parameters are set as follows:
danielk1977deb802c2006-02-09 13:43:28 +00004135**
drh6ed48bf2007-06-14 20:57:18 +00004136** <pre>
danielk1977deb802c2006-02-09 13:43:28 +00004137** data type: "INTEGER"
4138** collation sequence: "BINARY"
4139** not null: 0
4140** primary key: 1
4141** auto increment: 0
drhd68eee02009-12-11 03:44:18 +00004142** </pre>)^
danielk1977deb802c2006-02-09 13:43:28 +00004143**
drhd68eee02009-12-11 03:44:18 +00004144** ^(This function may load one or more schemas from database files. If an
danielk1977deb802c2006-02-09 13:43:28 +00004145** error occurs during this process, or if the requested table or column
mihailimdc884822008-06-22 08:58:50 +00004146** cannot be found, an [error code] is returned and an error message left
drhd68eee02009-12-11 03:44:18 +00004147** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
danielk19774b1ae992006-02-10 03:06:10 +00004148**
drhd68eee02009-12-11 03:44:18 +00004149** ^This API is only available if the library was compiled with the
drh4ead1482008-06-26 18:16:05 +00004150** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
danielk1977deb802c2006-02-09 13:43:28 +00004151*/
4152int sqlite3_table_column_metadata(
4153 sqlite3 *db, /* Connection handle */
4154 const char *zDbName, /* Database name or NULL */
4155 const char *zTableName, /* Table name */
4156 const char *zColumnName, /* Column name */
4157 char const **pzDataType, /* OUTPUT: Declared data type */
4158 char const **pzCollSeq, /* OUTPUT: Collation sequence name */
4159 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
4160 int *pPrimaryKey, /* OUTPUT: True if column part of PK */
drh98c94802007-10-01 13:50:31 +00004161 int *pAutoinc /* OUTPUT: True if column is auto-increment */
danielk1977deb802c2006-02-09 13:43:28 +00004162);
4163
4164/*
drhd68eee02009-12-11 03:44:18 +00004165** CAPI3REF: Load An Extension
drh1e397f82006-06-08 15:28:43 +00004166**
drhd68eee02009-12-11 03:44:18 +00004167** ^This interface loads an SQLite extension library from the named file.
drh1e397f82006-06-08 15:28:43 +00004168**
drhd68eee02009-12-11 03:44:18 +00004169** ^The sqlite3_load_extension() interface attempts to load an
4170** SQLite extension library contained in the file zFile.
drh1e397f82006-06-08 15:28:43 +00004171**
drhd68eee02009-12-11 03:44:18 +00004172** ^The entry point is zProc.
4173** ^zProc may be 0, in which case the name of the entry point
4174** defaults to "sqlite3_extension_init".
4175** ^The sqlite3_load_extension() interface returns
4176** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
4177** ^If an error occurs and pzErrMsg is not 0, then the
4178** [sqlite3_load_extension()] interface shall attempt to
4179** fill *pzErrMsg with error message text stored in memory
4180** obtained from [sqlite3_malloc()]. The calling function
4181** should free this memory by calling [sqlite3_free()].
mihailimdc884822008-06-22 08:58:50 +00004182**
drhd68eee02009-12-11 03:44:18 +00004183** ^Extension loading must be enabled using
4184** [sqlite3_enable_load_extension()] prior to calling this API,
4185** otherwise an error will be returned.
drha94cc422009-12-03 01:01:02 +00004186**
4187** See also the [load_extension() SQL function].
drh1e397f82006-06-08 15:28:43 +00004188*/
4189int sqlite3_load_extension(
4190 sqlite3 *db, /* Load the extension into this database connection */
4191 const char *zFile, /* Name of the shared library containing extension */
4192 const char *zProc, /* Entry point. Derived from zFile if 0 */
4193 char **pzErrMsg /* Put error message here if not 0 */
4194);
4195
4196/*
drhd68eee02009-12-11 03:44:18 +00004197** CAPI3REF: Enable Or Disable Extension Loading
drh6ed48bf2007-06-14 20:57:18 +00004198**
drhd68eee02009-12-11 03:44:18 +00004199** ^So as not to open security holes in older applications that are
drh6ed48bf2007-06-14 20:57:18 +00004200** unprepared to deal with extension loading, and as a means of disabling
mihailimdc884822008-06-22 08:58:50 +00004201** extension loading while evaluating user-entered SQL, the following API
4202** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
drhc2e87a32006-06-27 15:16:14 +00004203**
drhd68eee02009-12-11 03:44:18 +00004204** ^Extension loading is off by default. See ticket #1863.
4205** ^Call the sqlite3_enable_load_extension() routine with onoff==1
4206** to turn extension loading on and call it with onoff==0 to turn
4207** it back off again.
drhc2e87a32006-06-27 15:16:14 +00004208*/
4209int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
4210
4211/*
drhd68eee02009-12-11 03:44:18 +00004212** CAPI3REF: Automatically Load An Extensions
drh9eff6162006-06-12 21:59:13 +00004213**
drhd68eee02009-12-11 03:44:18 +00004214** ^This API can be invoked at program startup in order to register
drh1409be62006-08-23 20:07:20 +00004215** one or more statically linked extensions that will be available
drhd68eee02009-12-11 03:44:18 +00004216** to all new [database connections].
mihailimdc884822008-06-22 08:58:50 +00004217**
drhd68eee02009-12-11 03:44:18 +00004218** ^(This routine stores a pointer to the extension entry point
4219** in an array that is obtained from [sqlite3_malloc()]. That memory
4220** is deallocated by [sqlite3_reset_auto_extension()].)^
mihailimdc884822008-06-22 08:58:50 +00004221**
drhd68eee02009-12-11 03:44:18 +00004222** ^This function registers an extension entry point that is
4223** automatically invoked whenever a new [database connection]
4224** is opened using [sqlite3_open()], [sqlite3_open16()],
4225** or [sqlite3_open_v2()].
4226** ^Duplicate extensions are detected so calling this routine
4227** multiple times with the same extension is harmless.
4228** ^Automatic extensions apply across all threads.
drh1409be62006-08-23 20:07:20 +00004229*/
drh1875f7a2008-12-08 18:19:17 +00004230int sqlite3_auto_extension(void (*xEntryPoint)(void));
drh1409be62006-08-23 20:07:20 +00004231
drh1409be62006-08-23 20:07:20 +00004232/*
drhd68eee02009-12-11 03:44:18 +00004233** CAPI3REF: Reset Automatic Extension Loading
drh1409be62006-08-23 20:07:20 +00004234**
drhd68eee02009-12-11 03:44:18 +00004235** ^(This function disables all previously registered automatic
4236** extensions. It undoes the effect of all prior
4237** [sqlite3_auto_extension()] calls.)^
drh6ed48bf2007-06-14 20:57:18 +00004238**
drhd68eee02009-12-11 03:44:18 +00004239** ^This function disables automatic extensions in all threads.
drh1409be62006-08-23 20:07:20 +00004240*/
4241void sqlite3_reset_auto_extension(void);
4242
drh1409be62006-08-23 20:07:20 +00004243/*
drh9eff6162006-06-12 21:59:13 +00004244** The interface to the virtual-table mechanism is currently considered
4245** to be experimental. The interface might change in incompatible ways.
4246** If this is a problem for you, do not use the interface at this time.
4247**
shane26b34032008-05-23 17:21:09 +00004248** When the virtual-table mechanism stabilizes, we will declare the
drh9eff6162006-06-12 21:59:13 +00004249** interface fixed, support it indefinitely, and remove this comment.
4250*/
4251
4252/*
4253** Structures used by the virtual table interface
drhe09daa92006-06-10 13:29:31 +00004254*/
4255typedef struct sqlite3_vtab sqlite3_vtab;
4256typedef struct sqlite3_index_info sqlite3_index_info;
4257typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
4258typedef struct sqlite3_module sqlite3_module;
drh9eff6162006-06-12 21:59:13 +00004259
4260/*
drhd68eee02009-12-11 03:44:18 +00004261** CAPI3REF: Virtual Table Object
drh9cff9dc2009-04-13 14:43:40 +00004262** KEYWORDS: sqlite3_module {virtual table module}
drhb4d58ae2008-02-21 20:17:06 +00004263**
drh9cff9dc2009-04-13 14:43:40 +00004264** This structure, sometimes called a a "virtual table module",
4265** defines the implementation of a [virtual tables].
4266** This structure consists mostly of methods for the module.
mihailim15194222008-06-22 09:55:14 +00004267**
drhd68eee02009-12-11 03:44:18 +00004268** ^A virtual table module is created by filling in a persistent
drh9cff9dc2009-04-13 14:43:40 +00004269** instance of this structure and passing a pointer to that instance
4270** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
drhd68eee02009-12-11 03:44:18 +00004271** ^The registration remains valid until it is replaced by a different
drh9cff9dc2009-04-13 14:43:40 +00004272** module or until the [database connection] closes. The content
4273** of this structure must not change while it is registered with
4274** any database connection.
drh9eff6162006-06-12 21:59:13 +00004275*/
drhe09daa92006-06-10 13:29:31 +00004276struct sqlite3_module {
4277 int iVersion;
danielk19779da9d472006-06-14 06:58:15 +00004278 int (*xCreate)(sqlite3*, void *pAux,
drhe4102962006-09-11 00:34:22 +00004279 int argc, const char *const*argv,
drh4ca8aac2006-09-10 17:31:58 +00004280 sqlite3_vtab **ppVTab, char**);
danielk19779da9d472006-06-14 06:58:15 +00004281 int (*xConnect)(sqlite3*, void *pAux,
drhe4102962006-09-11 00:34:22 +00004282 int argc, const char *const*argv,
drh4ca8aac2006-09-10 17:31:58 +00004283 sqlite3_vtab **ppVTab, char**);
drhe09daa92006-06-10 13:29:31 +00004284 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
4285 int (*xDisconnect)(sqlite3_vtab *pVTab);
4286 int (*xDestroy)(sqlite3_vtab *pVTab);
4287 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
4288 int (*xClose)(sqlite3_vtab_cursor*);
drh4be8b512006-06-13 23:51:34 +00004289 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
drhe09daa92006-06-10 13:29:31 +00004290 int argc, sqlite3_value **argv);
4291 int (*xNext)(sqlite3_vtab_cursor*);
danielk1977a298e902006-06-22 09:53:48 +00004292 int (*xEof)(sqlite3_vtab_cursor*);
drhe09daa92006-06-10 13:29:31 +00004293 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
drh6d2069d2007-08-14 01:58:53 +00004294 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
4295 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
drhe09daa92006-06-10 13:29:31 +00004296 int (*xBegin)(sqlite3_vtab *pVTab);
4297 int (*xSync)(sqlite3_vtab *pVTab);
4298 int (*xCommit)(sqlite3_vtab *pVTab);
4299 int (*xRollback)(sqlite3_vtab *pVTab);
drhb7f6f682006-07-08 17:06:43 +00004300 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
drhe94b0c32006-07-08 18:09:15 +00004301 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
4302 void **ppArg);
danielk1977182c4ba2007-06-27 15:53:34 +00004303 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
drhe09daa92006-06-10 13:29:31 +00004304};
drh9eff6162006-06-12 21:59:13 +00004305
4306/*
drhd68eee02009-12-11 03:44:18 +00004307** CAPI3REF: Virtual Table Indexing Information
drhb4d58ae2008-02-21 20:17:06 +00004308** KEYWORDS: sqlite3_index_info
4309**
drh9eff6162006-06-12 21:59:13 +00004310** The sqlite3_index_info structure and its substructures is used to
drh9cff9dc2009-04-13 14:43:40 +00004311** pass information into and receive the reply from the [xBestIndex]
4312** method of a [virtual table module]. The fields under **Inputs** are the
drh9eff6162006-06-12 21:59:13 +00004313** inputs to xBestIndex and are read-only. xBestIndex inserts its
4314** results into the **Outputs** fields.
4315**
drhd68eee02009-12-11 03:44:18 +00004316** ^(The aConstraint[] array records WHERE clause constraints of the form:
drh9eff6162006-06-12 21:59:13 +00004317**
mihailim15194222008-06-22 09:55:14 +00004318** <pre>column OP expr</pre>
drh9eff6162006-06-12 21:59:13 +00004319**
drhdf6473a2009-12-13 22:20:08 +00004320** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^ ^(The particular operator is
drh7a98b852009-12-13 23:03:01 +00004321** stored in aConstraint[].op.)^ ^(The index of the column is stored in
4322** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
drh9eff6162006-06-12 21:59:13 +00004323** expr on the right-hand side can be evaluated (and thus the constraint
drhd68eee02009-12-11 03:44:18 +00004324** is usable) and false if it cannot.)^
drh9eff6162006-06-12 21:59:13 +00004325**
drhd68eee02009-12-11 03:44:18 +00004326** ^The optimizer automatically inverts terms of the form "expr OP column"
drh98c94802007-10-01 13:50:31 +00004327** and makes other simplifications to the WHERE clause in an attempt to
drh9eff6162006-06-12 21:59:13 +00004328** get as many WHERE clause terms into the form shown above as possible.
drhdf6473a2009-12-13 22:20:08 +00004329** ^The aConstraint[] array only reports WHERE clause terms that are
4330** relevant to the particular virtual table being queried.
drh9eff6162006-06-12 21:59:13 +00004331**
drhd68eee02009-12-11 03:44:18 +00004332** ^Information about the ORDER BY clause is stored in aOrderBy[].
4333** ^Each term of aOrderBy records a column of the ORDER BY clause.
drh9eff6162006-06-12 21:59:13 +00004334**
drh9cff9dc2009-04-13 14:43:40 +00004335** The [xBestIndex] method must fill aConstraintUsage[] with information
drhd68eee02009-12-11 03:44:18 +00004336** about what parameters to pass to xFilter. ^If argvIndex>0 then
drh9eff6162006-06-12 21:59:13 +00004337** the right-hand side of the corresponding aConstraint[] is evaluated
drhd68eee02009-12-11 03:44:18 +00004338** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
drh9eff6162006-06-12 21:59:13 +00004339** is true, then the constraint is assumed to be fully handled by the
drhd68eee02009-12-11 03:44:18 +00004340** virtual table and is not checked again by SQLite.)^
drh9eff6162006-06-12 21:59:13 +00004341**
drhd68eee02009-12-11 03:44:18 +00004342** ^The idxNum and idxPtr values are recorded and passed into the
drh9cff9dc2009-04-13 14:43:40 +00004343** [xFilter] method.
drh7a98b852009-12-13 23:03:01 +00004344** ^[sqlite3_free()] is used to free idxPtr if and only if
drh9cff9dc2009-04-13 14:43:40 +00004345** needToFreeIdxPtr is true.
drh9eff6162006-06-12 21:59:13 +00004346**
drhd68eee02009-12-11 03:44:18 +00004347** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
drh9eff6162006-06-12 21:59:13 +00004348** the correct order to satisfy the ORDER BY clause so that no separate
4349** sorting step is required.
4350**
drhd68eee02009-12-11 03:44:18 +00004351** ^The estimatedCost value is an estimate of the cost of doing the
drh9eff6162006-06-12 21:59:13 +00004352** particular lookup. A full scan of a table with N entries should have
4353** a cost of N. A binary search of a table of N entries should have a
4354** cost of approximately log(N).
4355*/
drhe09daa92006-06-10 13:29:31 +00004356struct sqlite3_index_info {
4357 /* Inputs */
drh6cca08c2007-09-21 12:43:16 +00004358 int nConstraint; /* Number of entries in aConstraint */
4359 struct sqlite3_index_constraint {
drh9eff6162006-06-12 21:59:13 +00004360 int iColumn; /* Column on left-hand side of constraint */
4361 unsigned char op; /* Constraint operator */
4362 unsigned char usable; /* True if this constraint is usable */
4363 int iTermOffset; /* Used internally - xBestIndex should ignore */
drh6cca08c2007-09-21 12:43:16 +00004364 } *aConstraint; /* Table of WHERE clause constraints */
4365 int nOrderBy; /* Number of terms in the ORDER BY clause */
4366 struct sqlite3_index_orderby {
drh9eff6162006-06-12 21:59:13 +00004367 int iColumn; /* Column number */
4368 unsigned char desc; /* True for DESC. False for ASC. */
drh6cca08c2007-09-21 12:43:16 +00004369 } *aOrderBy; /* The ORDER BY clause */
drhe09daa92006-06-10 13:29:31 +00004370 /* Outputs */
drh9eff6162006-06-12 21:59:13 +00004371 struct sqlite3_index_constraint_usage {
4372 int argvIndex; /* if >0, constraint is part of argv to xFilter */
4373 unsigned char omit; /* Do not code a test for this constraint */
drh6cca08c2007-09-21 12:43:16 +00004374 } *aConstraintUsage;
drh4be8b512006-06-13 23:51:34 +00004375 int idxNum; /* Number used to identify the index */
4376 char *idxStr; /* String, possibly obtained from sqlite3_malloc */
4377 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
drh9eff6162006-06-12 21:59:13 +00004378 int orderByConsumed; /* True if output is already ordered */
4379 double estimatedCost; /* Estimated cost of using this index */
drhe09daa92006-06-10 13:29:31 +00004380};
drh9eff6162006-06-12 21:59:13 +00004381#define SQLITE_INDEX_CONSTRAINT_EQ 2
4382#define SQLITE_INDEX_CONSTRAINT_GT 4
4383#define SQLITE_INDEX_CONSTRAINT_LE 8
4384#define SQLITE_INDEX_CONSTRAINT_LT 16
4385#define SQLITE_INDEX_CONSTRAINT_GE 32
4386#define SQLITE_INDEX_CONSTRAINT_MATCH 64
4387
4388/*
drhd68eee02009-12-11 03:44:18 +00004389** CAPI3REF: Register A Virtual Table Implementation
drhb4d58ae2008-02-21 20:17:06 +00004390**
drhfb434032009-12-11 23:11:26 +00004391** ^These routines are used to register a new [virtual table module] name.
drhd68eee02009-12-11 03:44:18 +00004392** ^Module names must be registered before
drhdf6473a2009-12-13 22:20:08 +00004393** creating a new [virtual table] using the module and before using a
drh9cff9dc2009-04-13 14:43:40 +00004394** preexisting [virtual table] for the module.
mihailim15194222008-06-22 09:55:14 +00004395**
drhd68eee02009-12-11 03:44:18 +00004396** ^The module name is registered on the [database connection] specified
4397** by the first parameter. ^The name of the module is given by the
4398** second parameter. ^The third parameter is a pointer to
4399** the implementation of the [virtual table module]. ^The fourth
drh9cff9dc2009-04-13 14:43:40 +00004400** parameter is an arbitrary client data pointer that is passed through
4401** into the [xCreate] and [xConnect] methods of the virtual table module
4402** when a new virtual table is be being created or reinitialized.
4403**
drhfb434032009-12-11 23:11:26 +00004404** ^The sqlite3_create_module_v2() interface has a fifth parameter which
4405** is a pointer to a destructor for the pClientData. ^SQLite will
4406** invoke the destructor function (if it is not NULL) when SQLite
4407** no longer needs the pClientData pointer. ^The sqlite3_create_module()
4408** interface is equivalent to sqlite3_create_module_v2() with a NULL
4409** destructor.
drh9eff6162006-06-12 21:59:13 +00004410*/
drh9f8da322010-03-10 20:06:37 +00004411int sqlite3_create_module(
drh9eff6162006-06-12 21:59:13 +00004412 sqlite3 *db, /* SQLite connection to register module with */
4413 const char *zName, /* Name of the module */
drh9cff9dc2009-04-13 14:43:40 +00004414 const sqlite3_module *p, /* Methods for the module */
4415 void *pClientData /* Client data for xCreate/xConnect */
drhb9bb7c12006-06-11 23:41:55 +00004416);
drh9f8da322010-03-10 20:06:37 +00004417int sqlite3_create_module_v2(
danielk1977832a58a2007-06-22 15:21:15 +00004418 sqlite3 *db, /* SQLite connection to register module with */
4419 const char *zName, /* Name of the module */
drh9cff9dc2009-04-13 14:43:40 +00004420 const sqlite3_module *p, /* Methods for the module */
4421 void *pClientData, /* Client data for xCreate/xConnect */
danielk1977832a58a2007-06-22 15:21:15 +00004422 void(*xDestroy)(void*) /* Module destructor function */
4423);
4424
4425/*
drhd68eee02009-12-11 03:44:18 +00004426** CAPI3REF: Virtual Table Instance Object
drhb4d58ae2008-02-21 20:17:06 +00004427** KEYWORDS: sqlite3_vtab
4428**
drh9cff9dc2009-04-13 14:43:40 +00004429** Every [virtual table module] implementation uses a subclass
drhd68eee02009-12-11 03:44:18 +00004430** of this object to describe a particular instance
drh9cff9dc2009-04-13 14:43:40 +00004431** of the [virtual table]. Each subclass will
mihailim15194222008-06-22 09:55:14 +00004432** be tailored to the specific needs of the module implementation.
4433** The purpose of this superclass is to define certain fields that are
4434** common to all module implementations.
drhfe1368e2006-09-10 17:08:29 +00004435**
drhd68eee02009-12-11 03:44:18 +00004436** ^Virtual tables methods can set an error message by assigning a
mihailim15194222008-06-22 09:55:14 +00004437** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
4438** take care that any prior string is freed by a call to [sqlite3_free()]
drhd68eee02009-12-11 03:44:18 +00004439** prior to assigning a new string to zErrMsg. ^After the error message
drhfe1368e2006-09-10 17:08:29 +00004440** is delivered up to the client application, the string will be automatically
drh9cff9dc2009-04-13 14:43:40 +00004441** freed by sqlite3_free() and the zErrMsg field will be zeroed.
drh9eff6162006-06-12 21:59:13 +00004442*/
4443struct sqlite3_vtab {
drha967e882006-06-13 01:04:52 +00004444 const sqlite3_module *pModule; /* The module for this virtual table */
danielk1977595a5232009-07-24 17:58:53 +00004445 int nRef; /* NO LONGER USED */
drh4ca8aac2006-09-10 17:31:58 +00004446 char *zErrMsg; /* Error message from sqlite3_mprintf() */
drh9eff6162006-06-12 21:59:13 +00004447 /* Virtual table implementations will typically add additional fields */
4448};
4449
drhb4d58ae2008-02-21 20:17:06 +00004450/*
drhd68eee02009-12-11 03:44:18 +00004451** CAPI3REF: Virtual Table Cursor Object
drh9cff9dc2009-04-13 14:43:40 +00004452** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
drhb4d58ae2008-02-21 20:17:06 +00004453**
drh9cff9dc2009-04-13 14:43:40 +00004454** Every [virtual table module] implementation uses a subclass of the
4455** following structure to describe cursors that point into the
4456** [virtual table] and are used
drh9eff6162006-06-12 21:59:13 +00004457** to loop through the virtual table. Cursors are created using the
drh9cff9dc2009-04-13 14:43:40 +00004458** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
drhd68eee02009-12-11 03:44:18 +00004459** by the [sqlite3_module.xClose | xClose] method. Cursors are used
drh9cff9dc2009-04-13 14:43:40 +00004460** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
4461** of the module. Each module implementation will define
drh9eff6162006-06-12 21:59:13 +00004462** the content of a cursor structure to suit its own needs.
4463**
4464** This superclass exists in order to define fields of the cursor that
4465** are common to all implementations.
4466*/
4467struct sqlite3_vtab_cursor {
4468 sqlite3_vtab *pVtab; /* Virtual table of this cursor */
4469 /* Virtual table implementations will typically add additional fields */
4470};
4471
4472/*
drhd68eee02009-12-11 03:44:18 +00004473** CAPI3REF: Declare The Schema Of A Virtual Table
drhb4d58ae2008-02-21 20:17:06 +00004474**
drhd68eee02009-12-11 03:44:18 +00004475** ^The [xCreate] and [xConnect] methods of a
drh9cff9dc2009-04-13 14:43:40 +00004476** [virtual table module] call this interface
drh9eff6162006-06-12 21:59:13 +00004477** to declare the format (the names and datatypes of the columns) of
4478** the virtual tables they implement.
4479*/
drh9f8da322010-03-10 20:06:37 +00004480int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
drhe09daa92006-06-10 13:29:31 +00004481
4482/*
drhd68eee02009-12-11 03:44:18 +00004483** CAPI3REF: Overload A Function For A Virtual Table
drhb4d58ae2008-02-21 20:17:06 +00004484**
drhd68eee02009-12-11 03:44:18 +00004485** ^(Virtual tables can provide alternative implementations of functions
drh9cff9dc2009-04-13 14:43:40 +00004486** using the [xFindFunction] method of the [virtual table module].
4487** But global versions of those functions
drh7a98b852009-12-13 23:03:01 +00004488** must exist in order to be overloaded.)^
drhb7481e72006-09-16 21:45:14 +00004489**
drhd68eee02009-12-11 03:44:18 +00004490** ^(This API makes sure a global version of a function with a particular
drhb7481e72006-09-16 21:45:14 +00004491** name and number of parameters exists. If no such function exists
drhd68eee02009-12-11 03:44:18 +00004492** before this API is called, a new function is created.)^ ^The implementation
drhb7481e72006-09-16 21:45:14 +00004493** of the new function always causes an exception to be thrown. So
4494** the new function is not good for anything by itself. Its only
shane26b34032008-05-23 17:21:09 +00004495** purpose is to be a placeholder function that can be overloaded
drh9cff9dc2009-04-13 14:43:40 +00004496** by a [virtual table].
drhb7481e72006-09-16 21:45:14 +00004497*/
drh9f8da322010-03-10 20:06:37 +00004498int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
drhb7481e72006-09-16 21:45:14 +00004499
4500/*
drh9eff6162006-06-12 21:59:13 +00004501** The interface to the virtual-table mechanism defined above (back up
4502** to a comment remarkably similar to this one) is currently considered
4503** to be experimental. The interface might change in incompatible ways.
4504** If this is a problem for you, do not use the interface at this time.
4505**
drh98c94802007-10-01 13:50:31 +00004506** When the virtual-table mechanism stabilizes, we will declare the
drh9eff6162006-06-12 21:59:13 +00004507** interface fixed, support it indefinitely, and remove this comment.
drh9eff6162006-06-12 21:59:13 +00004508*/
4509
danielk19778cbadb02007-05-03 16:31:26 +00004510/*
drhd68eee02009-12-11 03:44:18 +00004511** CAPI3REF: A Handle To An Open BLOB
mihailim15194222008-06-22 09:55:14 +00004512** KEYWORDS: {BLOB handle} {BLOB handles}
drh6ed48bf2007-06-14 20:57:18 +00004513**
drhb4d58ae2008-02-21 20:17:06 +00004514** An instance of this object represents an open BLOB on which
mihailim1c492652008-06-21 18:02:16 +00004515** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
drhd68eee02009-12-11 03:44:18 +00004516** ^Objects of this type are created by [sqlite3_blob_open()]
mihailim15194222008-06-22 09:55:14 +00004517** and destroyed by [sqlite3_blob_close()].
drhd68eee02009-12-11 03:44:18 +00004518** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
mihailim15194222008-06-22 09:55:14 +00004519** can be used to read or write small subsections of the BLOB.
drhd68eee02009-12-11 03:44:18 +00004520** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
danielk19778cbadb02007-05-03 16:31:26 +00004521*/
danielk1977b4e9af92007-05-01 17:49:49 +00004522typedef struct sqlite3_blob sqlite3_blob;
4523
danielk19778cbadb02007-05-03 16:31:26 +00004524/*
drhfb434032009-12-11 23:11:26 +00004525** CAPI3REF: Open A BLOB For Incremental I/O
drh6ed48bf2007-06-14 20:57:18 +00004526**
drhd68eee02009-12-11 03:44:18 +00004527** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
drhf84ddc12008-03-24 12:51:46 +00004528** in row iRow, column zColumn, table zTable in database zDb;
mihailim15194222008-06-22 09:55:14 +00004529** in other words, the same BLOB that would be selected by:
danielk19778cbadb02007-05-03 16:31:26 +00004530**
drh6ed48bf2007-06-14 20:57:18 +00004531** <pre>
drh49c3d572008-12-15 22:51:38 +00004532** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
drhd68eee02009-12-11 03:44:18 +00004533** </pre>)^
danielk19778cbadb02007-05-03 16:31:26 +00004534**
drhd68eee02009-12-11 03:44:18 +00004535** ^If the flags parameter is non-zero, then the BLOB is opened for read
4536** and write access. ^If it is zero, the BLOB is opened for read access.
4537** ^It is not possible to open a column that is part of an index or primary
danfedd4802009-10-07 11:29:40 +00004538** key for writing. ^If [foreign key constraints] are enabled, it is
drhc4ad1e92009-10-10 14:29:30 +00004539** not possible to open a column that is part of a [child key] for writing.
danielk19778cbadb02007-05-03 16:31:26 +00004540**
drhd68eee02009-12-11 03:44:18 +00004541** ^Note that the database name is not the filename that contains
drhf84ddc12008-03-24 12:51:46 +00004542** the database but rather the symbolic name of the database that
drhd68eee02009-12-11 03:44:18 +00004543** appears after the AS keyword when the database is connected using [ATTACH].
4544** ^For the main database file, the database name is "main".
4545** ^For TEMP tables, the database name is "temp".
drhf84ddc12008-03-24 12:51:46 +00004546**
drhd68eee02009-12-11 03:44:18 +00004547** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
drhabda6112009-05-14 22:37:47 +00004548** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
drhd68eee02009-12-11 03:44:18 +00004549** to be a null pointer.)^
4550** ^This function sets the [database connection] error code and message
drhabda6112009-05-14 22:37:47 +00004551** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
drhd68eee02009-12-11 03:44:18 +00004552** functions. ^Note that the *ppBlob variable is always initialized in a
drhabda6112009-05-14 22:37:47 +00004553** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
4554** regardless of the success or failure of this routine.
mihailim15194222008-06-22 09:55:14 +00004555**
drhd68eee02009-12-11 03:44:18 +00004556** ^(If the row that a BLOB handle points to is modified by an
drh9de1b352008-06-26 15:04:57 +00004557** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
4558** then the BLOB handle is marked as "expired".
4559** This is true if any column of the row is changed, even a column
drhd68eee02009-12-11 03:44:18 +00004560** other than the one the BLOB handle is open on.)^
4561** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
drh9de1b352008-06-26 15:04:57 +00004562** a expired BLOB handle fail with an return code of [SQLITE_ABORT].
drhd68eee02009-12-11 03:44:18 +00004563** ^(Changes written into a BLOB prior to the BLOB expiring are not
drhdf6473a2009-12-13 22:20:08 +00004564** rolled back by the expiration of the BLOB. Such changes will eventually
drhd68eee02009-12-11 03:44:18 +00004565** commit if the transaction continues to completion.)^
drh9de1b352008-06-26 15:04:57 +00004566**
drhd68eee02009-12-11 03:44:18 +00004567** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
4568** the opened blob. ^The size of a blob may not be changed by this
drh9e42f8a2009-08-13 20:15:29 +00004569** interface. Use the [UPDATE] SQL command to change the size of a
drhabda6112009-05-14 22:37:47 +00004570** blob.
4571**
drhd68eee02009-12-11 03:44:18 +00004572** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
drhabda6112009-05-14 22:37:47 +00004573** and the built-in [zeroblob] SQL function can be used, if desired,
4574** to create an empty, zero-filled blob in which to read or write using
4575** this interface.
4576**
4577** To avoid a resource leak, every open [BLOB handle] should eventually
4578** be released by a call to [sqlite3_blob_close()].
danielk19778cbadb02007-05-03 16:31:26 +00004579*/
danielk1977b4e9af92007-05-01 17:49:49 +00004580int sqlite3_blob_open(
4581 sqlite3*,
4582 const char *zDb,
4583 const char *zTable,
4584 const char *zColumn,
drh6d2069d2007-08-14 01:58:53 +00004585 sqlite3_int64 iRow,
danielk1977b4e9af92007-05-01 17:49:49 +00004586 int flags,
4587 sqlite3_blob **ppBlob
4588);
4589
danielk19778cbadb02007-05-03 16:31:26 +00004590/*
drhd68eee02009-12-11 03:44:18 +00004591** CAPI3REF: Close A BLOB Handle
drh6ed48bf2007-06-14 20:57:18 +00004592**
drhd68eee02009-12-11 03:44:18 +00004593** ^Closes an open [BLOB handle].
drh2dd62be2007-12-04 13:22:43 +00004594**
drhd68eee02009-12-11 03:44:18 +00004595** ^Closing a BLOB shall cause the current transaction to commit
drhf5befa02007-12-06 02:42:07 +00004596** if there are no other BLOBs, no pending prepared statements, and the
mihailim15194222008-06-22 09:55:14 +00004597** database connection is in [autocommit mode].
drhd68eee02009-12-11 03:44:18 +00004598** ^If any writes were made to the BLOB, they might be held in cache
drhabda6112009-05-14 22:37:47 +00004599** until the close operation if they will fit.
mihailim15194222008-06-22 09:55:14 +00004600**
drhd68eee02009-12-11 03:44:18 +00004601** ^(Closing the BLOB often forces the changes
drh2dd62be2007-12-04 13:22:43 +00004602** out to disk and so if any I/O errors occur, they will likely occur
drhabda6112009-05-14 22:37:47 +00004603** at the time when the BLOB is closed. Any errors that occur during
drhd68eee02009-12-11 03:44:18 +00004604** closing are reported as a non-zero return value.)^
drh2dd62be2007-12-04 13:22:43 +00004605**
drhd68eee02009-12-11 03:44:18 +00004606** ^(The BLOB is closed unconditionally. Even if this routine returns
4607** an error code, the BLOB is still closed.)^
drhb4d58ae2008-02-21 20:17:06 +00004608**
drhd68eee02009-12-11 03:44:18 +00004609** ^Calling this routine with a null pointer (such as would be returned
4610** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
danielk19778cbadb02007-05-03 16:31:26 +00004611*/
danielk1977b4e9af92007-05-01 17:49:49 +00004612int sqlite3_blob_close(sqlite3_blob *);
4613
danielk19778cbadb02007-05-03 16:31:26 +00004614/*
drhd68eee02009-12-11 03:44:18 +00004615** CAPI3REF: Return The Size Of An Open BLOB
drh6ed48bf2007-06-14 20:57:18 +00004616**
drhd68eee02009-12-11 03:44:18 +00004617** ^Returns the size in bytes of the BLOB accessible via the
4618** successfully opened [BLOB handle] in its only argument. ^The
drhabda6112009-05-14 22:37:47 +00004619** incremental blob I/O routines can only read or overwriting existing
4620** blob content; they cannot change the size of a blob.
4621**
4622** This routine only works on a [BLOB handle] which has been created
4623** by a prior successful call to [sqlite3_blob_open()] and which has not
4624** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4625** to this routine results in undefined and probably undesirable behavior.
danielk19778cbadb02007-05-03 16:31:26 +00004626*/
danielk1977b4e9af92007-05-01 17:49:49 +00004627int sqlite3_blob_bytes(sqlite3_blob *);
4628
drh9eff6162006-06-12 21:59:13 +00004629/*
drhd68eee02009-12-11 03:44:18 +00004630** CAPI3REF: Read Data From A BLOB Incrementally
drh6ed48bf2007-06-14 20:57:18 +00004631**
drhd68eee02009-12-11 03:44:18 +00004632** ^(This function is used to read data from an open [BLOB handle] into a
mihailim15194222008-06-22 09:55:14 +00004633** caller-supplied buffer. N bytes of data are copied into buffer Z
drhd68eee02009-12-11 03:44:18 +00004634** from the open BLOB, starting at offset iOffset.)^
danielk19778cbadb02007-05-03 16:31:26 +00004635**
drhd68eee02009-12-11 03:44:18 +00004636** ^If offset iOffset is less than N bytes from the end of the BLOB,
4637** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
mihailim15194222008-06-22 09:55:14 +00004638** less than zero, [SQLITE_ERROR] is returned and no data is read.
drhd68eee02009-12-11 03:44:18 +00004639** ^The size of the blob (and hence the maximum value of N+iOffset)
drhabda6112009-05-14 22:37:47 +00004640** can be determined using the [sqlite3_blob_bytes()] interface.
drhf5befa02007-12-06 02:42:07 +00004641**
drhd68eee02009-12-11 03:44:18 +00004642** ^An attempt to read from an expired [BLOB handle] fails with an
drh9de1b352008-06-26 15:04:57 +00004643** error code of [SQLITE_ABORT].
4644**
drhd68eee02009-12-11 03:44:18 +00004645** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
4646** Otherwise, an [error code] or an [extended error code] is returned.)^
drhb4d58ae2008-02-21 20:17:06 +00004647**
drhabda6112009-05-14 22:37:47 +00004648** This routine only works on a [BLOB handle] which has been created
4649** by a prior successful call to [sqlite3_blob_open()] and which has not
4650** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4651** to this routine results in undefined and probably undesirable behavior.
4652**
4653** See also: [sqlite3_blob_write()].
danielk19778cbadb02007-05-03 16:31:26 +00004654*/
drhb4d58ae2008-02-21 20:17:06 +00004655int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
danielk19778cbadb02007-05-03 16:31:26 +00004656
4657/*
drhd68eee02009-12-11 03:44:18 +00004658** CAPI3REF: Write Data Into A BLOB Incrementally
drh6ed48bf2007-06-14 20:57:18 +00004659**
drhd68eee02009-12-11 03:44:18 +00004660** ^This function is used to write data into an open [BLOB handle] from a
4661** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
mihailim15194222008-06-22 09:55:14 +00004662** into the open BLOB, starting at offset iOffset.
danielk19778cbadb02007-05-03 16:31:26 +00004663**
drhd68eee02009-12-11 03:44:18 +00004664** ^If the [BLOB handle] passed as the first argument was not opened for
mihailim15194222008-06-22 09:55:14 +00004665** writing (the flags parameter to [sqlite3_blob_open()] was zero),
4666** this function returns [SQLITE_READONLY].
danielk19778cbadb02007-05-03 16:31:26 +00004667**
drhd68eee02009-12-11 03:44:18 +00004668** ^This function may only modify the contents of the BLOB; it is
mihailim15194222008-06-22 09:55:14 +00004669** not possible to increase the size of a BLOB using this API.
drhd68eee02009-12-11 03:44:18 +00004670** ^If offset iOffset is less than N bytes from the end of the BLOB,
4671** [SQLITE_ERROR] is returned and no data is written. ^If N is
drhf5befa02007-12-06 02:42:07 +00004672** less than zero [SQLITE_ERROR] is returned and no data is written.
drhabda6112009-05-14 22:37:47 +00004673** The size of the BLOB (and hence the maximum value of N+iOffset)
4674** can be determined using the [sqlite3_blob_bytes()] interface.
danielk19778cbadb02007-05-03 16:31:26 +00004675**
drhd68eee02009-12-11 03:44:18 +00004676** ^An attempt to write to an expired [BLOB handle] fails with an
4677** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
drh9de1b352008-06-26 15:04:57 +00004678** before the [BLOB handle] expired are not rolled back by the
4679** expiration of the handle, though of course those changes might
4680** have been overwritten by the statement that expired the BLOB handle
4681** or by other independent statements.
4682**
drhd68eee02009-12-11 03:44:18 +00004683** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
4684** Otherwise, an [error code] or an [extended error code] is returned.)^
drhb4d58ae2008-02-21 20:17:06 +00004685**
drhabda6112009-05-14 22:37:47 +00004686** This routine only works on a [BLOB handle] which has been created
4687** by a prior successful call to [sqlite3_blob_open()] and which has not
4688** been closed by [sqlite3_blob_close()]. Passing any other pointer in
4689** to this routine results in undefined and probably undesirable behavior.
4690**
4691** See also: [sqlite3_blob_read()].
danielk19778cbadb02007-05-03 16:31:26 +00004692*/
4693int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
4694
drhd84f9462007-08-15 11:28:56 +00004695/*
drhd68eee02009-12-11 03:44:18 +00004696** CAPI3REF: Virtual File System Objects
drhd84f9462007-08-15 11:28:56 +00004697**
4698** A virtual filesystem (VFS) is an [sqlite3_vfs] object
4699** that SQLite uses to interact
drhb4d58ae2008-02-21 20:17:06 +00004700** with the underlying operating system. Most SQLite builds come with a
drhd84f9462007-08-15 11:28:56 +00004701** single default VFS that is appropriate for the host computer.
4702** New VFSes can be registered and existing VFSes can be unregistered.
4703** The following interfaces are provided.
4704**
drhd68eee02009-12-11 03:44:18 +00004705** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
4706** ^Names are case sensitive.
4707** ^Names are zero-terminated UTF-8 strings.
4708** ^If there is no match, a NULL pointer is returned.
4709** ^If zVfsName is NULL then the default VFS is returned.
drhd84f9462007-08-15 11:28:56 +00004710**
drhd68eee02009-12-11 03:44:18 +00004711** ^New VFSes are registered with sqlite3_vfs_register().
4712** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
4713** ^The same VFS can be registered multiple times without injury.
4714** ^To make an existing VFS into the default VFS, register it again
drhb4d58ae2008-02-21 20:17:06 +00004715** with the makeDflt flag set. If two different VFSes with the
4716** same name are registered, the behavior is undefined. If a
drhb6f5cf32007-08-28 15:21:45 +00004717** VFS is registered with a name that is NULL or an empty string,
4718** then the behavior is undefined.
mihailim15194222008-06-22 09:55:14 +00004719**
drhd68eee02009-12-11 03:44:18 +00004720** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
4721** ^(If the default VFS is unregistered, another VFS is chosen as
4722** the default. The choice for the new VFS is arbitrary.)^
drhd84f9462007-08-15 11:28:56 +00004723*/
drhd677b3d2007-08-20 22:48:41 +00004724sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
drhd677b3d2007-08-20 22:48:41 +00004725int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
4726int sqlite3_vfs_unregister(sqlite3_vfs*);
drhd84f9462007-08-15 11:28:56 +00004727
4728/*
drhd68eee02009-12-11 03:44:18 +00004729** CAPI3REF: Mutexes
drhd84f9462007-08-15 11:28:56 +00004730**
4731** The SQLite core uses these routines for thread
danielk19774a9d1f62008-06-19 08:51:23 +00004732** synchronization. Though they are intended for internal
drhd84f9462007-08-15 11:28:56 +00004733** use by SQLite, code that links against SQLite is
4734** permitted to use any of these routines.
4735**
mihailim15194222008-06-22 09:55:14 +00004736** The SQLite source code contains multiple implementations
drh8bacf972007-08-25 16:21:29 +00004737** of these mutex routines. An appropriate implementation
drhd68eee02009-12-11 03:44:18 +00004738** is selected automatically at compile-time. ^(The following
drh8bacf972007-08-25 16:21:29 +00004739** implementations are available in the SQLite core:
drhd84f9462007-08-15 11:28:56 +00004740**
4741** <ul>
drhc7ce76a2007-08-30 14:10:30 +00004742** <li> SQLITE_MUTEX_OS2
drhd84f9462007-08-15 11:28:56 +00004743** <li> SQLITE_MUTEX_PTHREAD
drhc7ce76a2007-08-30 14:10:30 +00004744** <li> SQLITE_MUTEX_W32
drhd84f9462007-08-15 11:28:56 +00004745** <li> SQLITE_MUTEX_NOOP
drhd68eee02009-12-11 03:44:18 +00004746** </ul>)^
drhd84f9462007-08-15 11:28:56 +00004747**
drhd68eee02009-12-11 03:44:18 +00004748** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
mihailim15194222008-06-22 09:55:14 +00004749** that does no real locking and is appropriate for use in
drhd68eee02009-12-11 03:44:18 +00004750** a single-threaded application. ^The SQLITE_MUTEX_OS2,
drhc7ce76a2007-08-30 14:10:30 +00004751** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
shane26b34032008-05-23 17:21:09 +00004752** are appropriate for use on OS/2, Unix, and Windows.
mihailim15194222008-06-22 09:55:14 +00004753**
drhd68eee02009-12-11 03:44:18 +00004754** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
drh8bacf972007-08-25 16:21:29 +00004755** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
danielk19774a9d1f62008-06-19 08:51:23 +00004756** implementation is included with the library. In this case the
4757** application must supply a custom mutex implementation using the
4758** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
mihailim15194222008-06-22 09:55:14 +00004759** before calling sqlite3_initialize() or any other public sqlite3_
drhd68eee02009-12-11 03:44:18 +00004760** function that calls sqlite3_initialize().)^
drhcb041342008-06-12 00:07:29 +00004761**
drhd68eee02009-12-11 03:44:18 +00004762** ^The sqlite3_mutex_alloc() routine allocates a new
4763** mutex and returns a pointer to it. ^If it returns NULL
4764** that means that a mutex could not be allocated. ^SQLite
4765** will unwind its stack and return an error. ^(The argument
drh6bdec4a2007-08-16 19:40:16 +00004766** to sqlite3_mutex_alloc() is one of these integer constants:
4767**
4768** <ul>
4769** <li> SQLITE_MUTEX_FAST
4770** <li> SQLITE_MUTEX_RECURSIVE
4771** <li> SQLITE_MUTEX_STATIC_MASTER
4772** <li> SQLITE_MUTEX_STATIC_MEM
drh86f8c192007-08-22 00:39:19 +00004773** <li> SQLITE_MUTEX_STATIC_MEM2
drh6bdec4a2007-08-16 19:40:16 +00004774** <li> SQLITE_MUTEX_STATIC_PRNG
danielk19779f61c2f2007-08-27 17:27:49 +00004775** <li> SQLITE_MUTEX_STATIC_LRU
danielk1977dfb316d2008-03-26 18:34:43 +00004776** <li> SQLITE_MUTEX_STATIC_LRU2
drhd68eee02009-12-11 03:44:18 +00004777** </ul>)^
drh6bdec4a2007-08-16 19:40:16 +00004778**
drhd68eee02009-12-11 03:44:18 +00004779** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
4780** cause sqlite3_mutex_alloc() to create
4781** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
4782** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
drh6bdec4a2007-08-16 19:40:16 +00004783** The mutex implementation does not need to make a distinction
4784** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
drhd68eee02009-12-11 03:44:18 +00004785** not want to. ^SQLite will only request a recursive mutex in
4786** cases where it really needs one. ^If a faster non-recursive mutex
drh6bdec4a2007-08-16 19:40:16 +00004787** implementation is available on the host platform, the mutex subsystem
4788** might return such a mutex in response to SQLITE_MUTEX_FAST.
4789**
drhd68eee02009-12-11 03:44:18 +00004790** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
4791** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
4792** a pointer to a static preexisting mutex. ^Six static mutexes are
drh6bdec4a2007-08-16 19:40:16 +00004793** used by the current version of SQLite. Future versions of SQLite
4794** may add additional static mutexes. Static mutexes are for internal
4795** use by SQLite only. Applications that use SQLite mutexes should
4796** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
4797** SQLITE_MUTEX_RECURSIVE.
4798**
drhd68eee02009-12-11 03:44:18 +00004799** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
drh6bdec4a2007-08-16 19:40:16 +00004800** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
drhd68eee02009-12-11 03:44:18 +00004801** returns a different mutex on every call. ^But for the static
drh6bdec4a2007-08-16 19:40:16 +00004802** mutex types, the same mutex is returned on every call that has
mihailim04bcc002008-06-22 10:21:27 +00004803** the same type number.
drhd84f9462007-08-15 11:28:56 +00004804**
drhd68eee02009-12-11 03:44:18 +00004805** ^The sqlite3_mutex_free() routine deallocates a previously
4806** allocated dynamic mutex. ^SQLite is careful to deallocate every
4807** dynamic mutex that it allocates. The dynamic mutexes must not be in
4808** use when they are deallocated. Attempting to deallocate a static
4809** mutex results in undefined behavior. ^SQLite never deallocates
4810** a static mutex.
drhd84f9462007-08-15 11:28:56 +00004811**
drhd68eee02009-12-11 03:44:18 +00004812** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
4813** to enter a mutex. ^If another thread is already within the mutex,
drh6bdec4a2007-08-16 19:40:16 +00004814** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
drhd68eee02009-12-11 03:44:18 +00004815** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
4816** upon successful entry. ^(Mutexes created using
drhf5befa02007-12-06 02:42:07 +00004817** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
drhd68eee02009-12-11 03:44:18 +00004818** In such cases the,
drh6bdec4a2007-08-16 19:40:16 +00004819** mutex must be exited an equal number of times before another thread
drhd68eee02009-12-11 03:44:18 +00004820** can enter.)^ ^(If the same thread tries to enter any other
drhf5befa02007-12-06 02:42:07 +00004821** kind of mutex more than once, the behavior is undefined.
drhd68eee02009-12-11 03:44:18 +00004822** SQLite will never exhibit
4823** such behavior in its own use of mutexes.)^
drhd84f9462007-08-15 11:28:56 +00004824**
drhd68eee02009-12-11 03:44:18 +00004825** ^(Some systems (for example, Windows 95) do not support the operation
mihailim15194222008-06-22 09:55:14 +00004826** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
drhd68eee02009-12-11 03:44:18 +00004827** will always return SQLITE_BUSY. The SQLite core only ever uses
4828** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
drhca49cba2007-09-04 22:31:36 +00004829**
drhd68eee02009-12-11 03:44:18 +00004830** ^The sqlite3_mutex_leave() routine exits a mutex that was
4831** previously entered by the same thread. ^(The behavior
drh8bacf972007-08-25 16:21:29 +00004832** is undefined if the mutex is not currently entered by the
drhd68eee02009-12-11 03:44:18 +00004833** calling thread or is not currently allocated. SQLite will
4834** never do either.)^
drh8bacf972007-08-25 16:21:29 +00004835**
drhd68eee02009-12-11 03:44:18 +00004836** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
drh40257ff2008-06-13 18:24:27 +00004837** sqlite3_mutex_leave() is a NULL pointer, then all three routines
4838** behave as no-ops.
4839**
drh8bacf972007-08-25 16:21:29 +00004840** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
4841*/
4842sqlite3_mutex *sqlite3_mutex_alloc(int);
4843void sqlite3_mutex_free(sqlite3_mutex*);
4844void sqlite3_mutex_enter(sqlite3_mutex*);
4845int sqlite3_mutex_try(sqlite3_mutex*);
4846void sqlite3_mutex_leave(sqlite3_mutex*);
4847
drh56a40a82008-06-18 13:47:03 +00004848/*
drhd68eee02009-12-11 03:44:18 +00004849** CAPI3REF: Mutex Methods Object
drh56a40a82008-06-18 13:47:03 +00004850**
4851** An instance of this structure defines the low-level routines
danielk19774a9d1f62008-06-19 08:51:23 +00004852** used to allocate and use mutexes.
4853**
4854** Usually, the default mutex implementations provided by SQLite are
mihailim15194222008-06-22 09:55:14 +00004855** sufficient, however the user has the option of substituting a custom
4856** implementation for specialized deployments or systems for which SQLite
danielk19774a9d1f62008-06-19 08:51:23 +00004857** does not provide a suitable implementation. In this case, the user
4858** creates and populates an instance of this structure to pass
mihailim15194222008-06-22 09:55:14 +00004859** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
danielk19774a9d1f62008-06-19 08:51:23 +00004860** Additionally, an instance of this structure can be used as an
4861** output variable when querying the system for the current mutex
4862** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
4863**
drhd68eee02009-12-11 03:44:18 +00004864** ^The xMutexInit method defined by this structure is invoked as
danielk19774a9d1f62008-06-19 08:51:23 +00004865** part of system initialization by the sqlite3_initialize() function.
drhd68eee02009-12-11 03:44:18 +00004866** ^The xMutexInit routine is calle by SQLite exactly once for each
mihailim15194222008-06-22 09:55:14 +00004867** effective call to [sqlite3_initialize()].
danielk19774a9d1f62008-06-19 08:51:23 +00004868**
drhd68eee02009-12-11 03:44:18 +00004869** ^The xMutexEnd method defined by this structure is invoked as
danielk19774a9d1f62008-06-19 08:51:23 +00004870** part of system shutdown by the sqlite3_shutdown() function. The
4871** implementation of this method is expected to release all outstanding
4872** resources obtained by the mutex methods implementation, especially
drhd68eee02009-12-11 03:44:18 +00004873** those obtained by the xMutexInit method. ^The xMutexEnd()
4874** interface is invoked exactly once for each call to [sqlite3_shutdown()].
danielk19774a9d1f62008-06-19 08:51:23 +00004875**
drhd68eee02009-12-11 03:44:18 +00004876** ^(The remaining seven methods defined by this structure (xMutexAlloc,
danielk19774a9d1f62008-06-19 08:51:23 +00004877** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
4878** xMutexNotheld) implement the following interfaces (respectively):
drh56a40a82008-06-18 13:47:03 +00004879**
4880** <ul>
danielk19774a9d1f62008-06-19 08:51:23 +00004881** <li> [sqlite3_mutex_alloc()] </li>
4882** <li> [sqlite3_mutex_free()] </li>
4883** <li> [sqlite3_mutex_enter()] </li>
4884** <li> [sqlite3_mutex_try()] </li>
4885** <li> [sqlite3_mutex_leave()] </li>
4886** <li> [sqlite3_mutex_held()] </li>
4887** <li> [sqlite3_mutex_notheld()] </li>
drhd68eee02009-12-11 03:44:18 +00004888** </ul>)^
danielk19774a9d1f62008-06-19 08:51:23 +00004889**
4890** The only difference is that the public sqlite3_XXX functions enumerated
4891** above silently ignore any invocations that pass a NULL pointer instead
4892** of a valid mutex handle. The implementations of the methods defined
4893** by this structure are not required to handle this case, the results
4894** of passing a NULL pointer instead of a valid mutex handle are undefined
4895** (i.e. it is acceptable to provide an implementation that segfaults if
4896** it is passed a NULL pointer).
drh9ac06502009-08-17 13:42:29 +00004897**
drhd68eee02009-12-11 03:44:18 +00004898** The xMutexInit() method must be threadsafe. ^It must be harmless to
drh9ac06502009-08-17 13:42:29 +00004899** invoke xMutexInit() mutiple times within the same process and without
4900** intervening calls to xMutexEnd(). Second and subsequent calls to
4901** xMutexInit() must be no-ops.
4902**
drhd68eee02009-12-11 03:44:18 +00004903** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
4904** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
4905** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
drh9ac06502009-08-17 13:42:29 +00004906** memory allocation for a fast or recursive mutex.
4907**
drhd68eee02009-12-11 03:44:18 +00004908** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
drh9ac06502009-08-17 13:42:29 +00004909** called, but only if the prior call to xMutexInit returned SQLITE_OK.
4910** If xMutexInit fails in any way, it is expected to clean up after itself
4911** prior to returning.
drh56a40a82008-06-18 13:47:03 +00004912*/
danielk19776d2ab0e2008-06-17 17:21:18 +00004913typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
4914struct sqlite3_mutex_methods {
4915 int (*xMutexInit)(void);
danielk19774a9d1f62008-06-19 08:51:23 +00004916 int (*xMutexEnd)(void);
danielk19776d2ab0e2008-06-17 17:21:18 +00004917 sqlite3_mutex *(*xMutexAlloc)(int);
4918 void (*xMutexFree)(sqlite3_mutex *);
4919 void (*xMutexEnter)(sqlite3_mutex *);
4920 int (*xMutexTry)(sqlite3_mutex *);
4921 void (*xMutexLeave)(sqlite3_mutex *);
danielk19776d2ab0e2008-06-17 17:21:18 +00004922 int (*xMutexHeld)(sqlite3_mutex *);
4923 int (*xMutexNotheld)(sqlite3_mutex *);
4924};
4925
drh8bacf972007-08-25 16:21:29 +00004926/*
drhd68eee02009-12-11 03:44:18 +00004927** CAPI3REF: Mutex Verification Routines
drhd677b3d2007-08-20 22:48:41 +00004928**
4929** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
drhd68eee02009-12-11 03:44:18 +00004930** are intended for use inside assert() statements. ^The SQLite core
drhf77a2ff2007-08-25 14:49:36 +00004931** never uses these routines except inside an assert() and applications
drhd68eee02009-12-11 03:44:18 +00004932** are advised to follow the lead of the core. ^The SQLite core only
drh8bacf972007-08-25 16:21:29 +00004933** provides implementations for these routines when it is compiled
drhd68eee02009-12-11 03:44:18 +00004934** with the SQLITE_DEBUG flag. ^External mutex implementations
drh8bacf972007-08-25 16:21:29 +00004935** are only required to provide these routines if SQLITE_DEBUG is
4936** defined and if NDEBUG is not defined.
4937**
drhd68eee02009-12-11 03:44:18 +00004938** ^These routines should return true if the mutex in their argument
mihailim04bcc002008-06-22 10:21:27 +00004939** is held or not held, respectively, by the calling thread.
drh8bacf972007-08-25 16:21:29 +00004940**
drhd68eee02009-12-11 03:44:18 +00004941** ^The implementation is not required to provided versions of these
mihailim04bcc002008-06-22 10:21:27 +00004942** routines that actually work. If the implementation does not provide working
4943** versions of these routines, it should at least provide stubs that always
4944** return true so that one does not get spurious assertion failures.
drhd677b3d2007-08-20 22:48:41 +00004945**
drhd68eee02009-12-11 03:44:18 +00004946** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
4947** the routine should return 1. This seems counter-intuitive since
drhd677b3d2007-08-20 22:48:41 +00004948** clearly the mutex cannot be held if it does not exist. But the
4949** the reason the mutex does not exist is because the build is not
4950** using mutexes. And we do not want the assert() containing the
4951** call to sqlite3_mutex_held() to fail, so a non-zero return is
drhd68eee02009-12-11 03:44:18 +00004952** the appropriate thing to do. ^The sqlite3_mutex_notheld()
drhd677b3d2007-08-20 22:48:41 +00004953** interface should also return 1 when given a NULL pointer.
drhd84f9462007-08-15 11:28:56 +00004954*/
drh0edb3cf2009-12-10 01:17:29 +00004955#ifndef NDEBUG
drhd677b3d2007-08-20 22:48:41 +00004956int sqlite3_mutex_held(sqlite3_mutex*);
4957int sqlite3_mutex_notheld(sqlite3_mutex*);
drh0edb3cf2009-12-10 01:17:29 +00004958#endif
drh32bc3f62007-08-21 20:25:39 +00004959
4960/*
drhd68eee02009-12-11 03:44:18 +00004961** CAPI3REF: Mutex Types
drh32bc3f62007-08-21 20:25:39 +00004962**
drhd5a68d32008-08-04 13:44:57 +00004963** The [sqlite3_mutex_alloc()] interface takes a single argument
mihailim04bcc002008-06-22 10:21:27 +00004964** which is one of these integer constants.
drhd5a68d32008-08-04 13:44:57 +00004965**
4966** The set of static mutexes may change from one SQLite release to the
4967** next. Applications that override the built-in mutex logic must be
4968** prepared to accommodate additional static mutexes.
drh32bc3f62007-08-21 20:25:39 +00004969*/
drh6bdec4a2007-08-16 19:40:16 +00004970#define SQLITE_MUTEX_FAST 0
4971#define SQLITE_MUTEX_RECURSIVE 1
4972#define SQLITE_MUTEX_STATIC_MASTER 2
drh86f8c192007-08-22 00:39:19 +00004973#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
drh7555d8e2009-03-20 13:15:30 +00004974#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
4975#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
drh86f8c192007-08-22 00:39:19 +00004976#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
danielk19779f61c2f2007-08-27 17:27:49 +00004977#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
danielk1977dfb316d2008-03-26 18:34:43 +00004978#define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */
drh6d2069d2007-08-14 01:58:53 +00004979
drhcc6bb3e2007-08-31 16:11:35 +00004980/*
drhd68eee02009-12-11 03:44:18 +00004981** CAPI3REF: Retrieve the mutex for a database connection
drh4413d0e2008-11-04 13:46:27 +00004982**
drhd68eee02009-12-11 03:44:18 +00004983** ^This interface returns a pointer the [sqlite3_mutex] object that
drh4413d0e2008-11-04 13:46:27 +00004984** serializes access to the [database connection] given in the argument
4985** when the [threading mode] is Serialized.
drhd68eee02009-12-11 03:44:18 +00004986** ^If the [threading mode] is Single-thread or Multi-thread then this
drh4413d0e2008-11-04 13:46:27 +00004987** routine returns a NULL pointer.
4988*/
4989sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
4990
4991/*
drhfb434032009-12-11 23:11:26 +00004992** CAPI3REF: Low-Level Control Of Database Files
drhcc6bb3e2007-08-31 16:11:35 +00004993**
drhd68eee02009-12-11 03:44:18 +00004994** ^The [sqlite3_file_control()] interface makes a direct call to the
drhcc6bb3e2007-08-31 16:11:35 +00004995** xFileControl method for the [sqlite3_io_methods] object associated
drhd68eee02009-12-11 03:44:18 +00004996** with a particular database identified by the second argument. ^The
4997** name of the database "main" for the main database or "temp" for the
4998** TEMP database, or the name that appears after the AS keyword for
4999** databases that are added using the [ATTACH] SQL command.
5000** ^A NULL pointer can be used in place of "main" to refer to the
5001** main database file.
5002** ^The third and fourth parameters to this routine
drhcc6bb3e2007-08-31 16:11:35 +00005003** are passed directly through to the second and third parameters of
drhd68eee02009-12-11 03:44:18 +00005004** the xFileControl method. ^The return value of the xFileControl
drhcc6bb3e2007-08-31 16:11:35 +00005005** method becomes the return value of this routine.
5006**
drhd68eee02009-12-11 03:44:18 +00005007** ^If the second parameter (zDbName) does not match the name of any
5008** open database file, then SQLITE_ERROR is returned. ^This error
drhcc6bb3e2007-08-31 16:11:35 +00005009** code is not remembered and will not be recalled by [sqlite3_errcode()]
drhd68eee02009-12-11 03:44:18 +00005010** or [sqlite3_errmsg()]. The underlying xFileControl method might
5011** also return SQLITE_ERROR. There is no way to distinguish between
drhcc6bb3e2007-08-31 16:11:35 +00005012** an incorrect zDbName and an SQLITE_ERROR return from the underlying
drhd68eee02009-12-11 03:44:18 +00005013** xFileControl method.
drh4ff7fa02007-09-01 18:17:21 +00005014**
5015** See also: [SQLITE_FCNTL_LOCKSTATE]
drhcc6bb3e2007-08-31 16:11:35 +00005016*/
5017int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
drh6d2069d2007-08-14 01:58:53 +00005018
danielk19778cbadb02007-05-03 16:31:26 +00005019/*
drhd68eee02009-12-11 03:44:18 +00005020** CAPI3REF: Testing Interface
drhed13d982008-01-31 14:43:24 +00005021**
drhd68eee02009-12-11 03:44:18 +00005022** ^The sqlite3_test_control() interface is used to read out internal
drhed13d982008-01-31 14:43:24 +00005023** state of SQLite and to inject faults into SQLite for testing
drhd68eee02009-12-11 03:44:18 +00005024** purposes. ^The first parameter is an operation code that determines
drhed13d982008-01-31 14:43:24 +00005025** the number, meaning, and operation of all subsequent parameters.
5026**
5027** This interface is not for use by applications. It exists solely
5028** for verifying the correct operation of the SQLite library. Depending
5029** on how the SQLite library is compiled, this interface might not exist.
5030**
5031** The details of the operation codes, their meanings, the parameters
5032** they take, and what they do are all subject to change without notice.
5033** Unlike most of the SQLite API, this function is not guaranteed to
5034** operate consistently from one release to the next.
5035*/
5036int sqlite3_test_control(int op, ...);
5037
5038/*
drhd68eee02009-12-11 03:44:18 +00005039** CAPI3REF: Testing Interface Operation Codes
drhed13d982008-01-31 14:43:24 +00005040**
5041** These constants are the valid operation code parameters used
5042** as the first argument to [sqlite3_test_control()].
5043**
shane26b34032008-05-23 17:21:09 +00005044** These parameters and their meanings are subject to change
drhed13d982008-01-31 14:43:24 +00005045** without notice. These values are for testing purposes only.
5046** Applications should not use any of these parameters or the
5047** [sqlite3_test_control()] interface.
5048*/
drh07096f62009-12-22 23:52:32 +00005049#define SQLITE_TESTCTRL_FIRST 5
drh2fa18682008-03-19 14:15:34 +00005050#define SQLITE_TESTCTRL_PRNG_SAVE 5
5051#define SQLITE_TESTCTRL_PRNG_RESTORE 6
5052#define SQLITE_TESTCTRL_PRNG_RESET 7
drh3088d592008-03-21 16:45:47 +00005053#define SQLITE_TESTCTRL_BITVEC_TEST 8
danielk1977d09414c2008-06-19 18:17:49 +00005054#define SQLITE_TESTCTRL_FAULT_INSTALL 9
danielk19772d1d86f2008-06-20 14:59:51 +00005055#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
drhc7a3bb92009-02-05 16:31:45 +00005056#define SQLITE_TESTCTRL_PENDING_BYTE 11
drhf3af63f2009-05-09 18:59:42 +00005057#define SQLITE_TESTCTRL_ASSERT 12
5058#define SQLITE_TESTCTRL_ALWAYS 13
drhc046e3e2009-07-15 11:26:44 +00005059#define SQLITE_TESTCTRL_RESERVE 14
drh07096f62009-12-22 23:52:32 +00005060#define SQLITE_TESTCTRL_OPTIMIZATIONS 15
drh0e857732010-01-02 03:21:35 +00005061#define SQLITE_TESTCTRL_ISKEYWORD 16
drh23e35722010-06-10 14:07:40 +00005062#define SQLITE_TESTCTRL_PGHDRSZ 17
5063#define SQLITE_TESTCTRL_LAST 17
drhed13d982008-01-31 14:43:24 +00005064
drhf7141992008-06-19 00:16:08 +00005065/*
drhd68eee02009-12-11 03:44:18 +00005066** CAPI3REF: SQLite Runtime Status
drhf7141992008-06-19 00:16:08 +00005067**
drhd68eee02009-12-11 03:44:18 +00005068** ^This interface is used to retrieve runtime status information
drhf7141992008-06-19 00:16:08 +00005069** about the preformance of SQLite, and optionally to reset various
drhd68eee02009-12-11 03:44:18 +00005070** highwater marks. ^The first argument is an integer code for
drhdf6473a2009-12-13 22:20:08 +00005071** the specific parameter to measure. ^(Recognized integer codes
5072** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...].)^
drhd68eee02009-12-11 03:44:18 +00005073** ^The current value of the parameter is returned into *pCurrent.
5074** ^The highest recorded value is returned in *pHighwater. ^If the
drhf7141992008-06-19 00:16:08 +00005075** resetFlag is true, then the highest record value is reset after
drhd68eee02009-12-11 03:44:18 +00005076** *pHighwater is written. ^(Some parameters do not record the highest
drhf7141992008-06-19 00:16:08 +00005077** value. For those parameters
drhd68eee02009-12-11 03:44:18 +00005078** nothing is written into *pHighwater and the resetFlag is ignored.)^
5079** ^(Other parameters record only the highwater mark and not the current
5080** value. For these latter parameters nothing is written into *pCurrent.)^
drhf7141992008-06-19 00:16:08 +00005081**
drhd68eee02009-12-11 03:44:18 +00005082** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
5083** non-zero [error code] on failure.
drhf7141992008-06-19 00:16:08 +00005084**
drh6aa5f152009-08-19 15:57:07 +00005085** This routine is threadsafe but is not atomic. This routine can be
drhf7141992008-06-19 00:16:08 +00005086** called while other threads are running the same or different SQLite
5087** interfaces. However the values returned in *pCurrent and
5088** *pHighwater reflect the status of SQLite at different points in time
5089** and it is possible that another thread might change the parameter
5090** in between the times when *pCurrent and *pHighwater are written.
5091**
drh2462e322008-07-31 14:47:54 +00005092** See also: [sqlite3_db_status()]
drhf7141992008-06-19 00:16:08 +00005093*/
drh9f8da322010-03-10 20:06:37 +00005094int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
drh2462e322008-07-31 14:47:54 +00005095
danielk1977075c23a2008-09-01 18:34:20 +00005096
drhf7141992008-06-19 00:16:08 +00005097/*
drhd68eee02009-12-11 03:44:18 +00005098** CAPI3REF: Status Parameters
drhf7141992008-06-19 00:16:08 +00005099**
5100** These integer constants designate various run-time status parameters
5101** that can be returned by [sqlite3_status()].
5102**
5103** <dl>
drhd68eee02009-12-11 03:44:18 +00005104** ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
drhf7141992008-06-19 00:16:08 +00005105** <dd>This parameter is the current amount of memory checked out
mihailim15194222008-06-22 09:55:14 +00005106** using [sqlite3_malloc()], either directly or indirectly. The
drhf7141992008-06-19 00:16:08 +00005107** figure includes calls made to [sqlite3_malloc()] by the application
5108** and internal memory usage by the SQLite library. Scratch memory
5109** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
5110** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
5111** this parameter. The amount returned is the sum of the allocation
drhd68eee02009-12-11 03:44:18 +00005112** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
drhf7141992008-06-19 00:16:08 +00005113**
drhd68eee02009-12-11 03:44:18 +00005114** ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
drhe50135e2008-08-05 17:53:22 +00005115** <dd>This parameter records the largest memory allocation request
5116** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
5117** internal equivalents). Only the value returned in the
5118** *pHighwater parameter to [sqlite3_status()] is of interest.
drhd68eee02009-12-11 03:44:18 +00005119** The value written into the *pCurrent parameter is undefined.</dd>)^
drhe50135e2008-08-05 17:53:22 +00005120**
drhd68eee02009-12-11 03:44:18 +00005121** ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
drhf7141992008-06-19 00:16:08 +00005122** <dd>This parameter returns the number of pages used out of the
drhe50135e2008-08-05 17:53:22 +00005123** [pagecache memory allocator] that was configured using
5124** [SQLITE_CONFIG_PAGECACHE]. The
drhd68eee02009-12-11 03:44:18 +00005125** value returned is in pages, not in bytes.</dd>)^
drhf7141992008-06-19 00:16:08 +00005126**
drhd68eee02009-12-11 03:44:18 +00005127** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
drhf7141992008-06-19 00:16:08 +00005128** <dd>This parameter returns the number of bytes of page cache
5129** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE]
drhe50135e2008-08-05 17:53:22 +00005130** buffer and where forced to overflow to [sqlite3_malloc()]. The
5131** returned value includes allocations that overflowed because they
5132** where too large (they were larger than the "sz" parameter to
5133** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
drhd68eee02009-12-11 03:44:18 +00005134** no space was left in the page cache.</dd>)^
drhe50135e2008-08-05 17:53:22 +00005135**
drhd68eee02009-12-11 03:44:18 +00005136** ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
drhe50135e2008-08-05 17:53:22 +00005137** <dd>This parameter records the largest memory allocation request
5138** handed to [pagecache memory allocator]. Only the value returned in the
5139** *pHighwater parameter to [sqlite3_status()] is of interest.
drhd68eee02009-12-11 03:44:18 +00005140** The value written into the *pCurrent parameter is undefined.</dd>)^
drhf7141992008-06-19 00:16:08 +00005141**
drhd68eee02009-12-11 03:44:18 +00005142** ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
drhf7141992008-06-19 00:16:08 +00005143** <dd>This parameter returns the number of allocations used out of the
drhe50135e2008-08-05 17:53:22 +00005144** [scratch memory allocator] configured using
drhf7141992008-06-19 00:16:08 +00005145** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
drhe50135e2008-08-05 17:53:22 +00005146** in bytes. Since a single thread may only have one scratch allocation
drhf7141992008-06-19 00:16:08 +00005147** outstanding at time, this parameter also reports the number of threads
drhd68eee02009-12-11 03:44:18 +00005148** using scratch memory at the same time.</dd>)^
drhf7141992008-06-19 00:16:08 +00005149**
drhd68eee02009-12-11 03:44:18 +00005150** ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
drhf7141992008-06-19 00:16:08 +00005151** <dd>This parameter returns the number of bytes of scratch memory
5152** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH]
drhe50135e2008-08-05 17:53:22 +00005153** buffer and where forced to overflow to [sqlite3_malloc()]. The values
5154** returned include overflows because the requested allocation was too
5155** larger (that is, because the requested allocation was larger than the
5156** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
5157** slots were available.
drhd68eee02009-12-11 03:44:18 +00005158** </dd>)^
drhf7141992008-06-19 00:16:08 +00005159**
drhd68eee02009-12-11 03:44:18 +00005160** ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
drhf7141992008-06-19 00:16:08 +00005161** <dd>This parameter records the largest memory allocation request
drhe50135e2008-08-05 17:53:22 +00005162** handed to [scratch memory allocator]. Only the value returned in the
5163** *pHighwater parameter to [sqlite3_status()] is of interest.
drhd68eee02009-12-11 03:44:18 +00005164** The value written into the *pCurrent parameter is undefined.</dd>)^
drhec424a52008-07-25 15:39:03 +00005165**
drhd68eee02009-12-11 03:44:18 +00005166** ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
drhec424a52008-07-25 15:39:03 +00005167** <dd>This parameter records the deepest parser stack. It is only
drhd68eee02009-12-11 03:44:18 +00005168** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
drhf7141992008-06-19 00:16:08 +00005169** </dl>
5170**
5171** New status parameters may be added from time to time.
5172*/
5173#define SQLITE_STATUS_MEMORY_USED 0
5174#define SQLITE_STATUS_PAGECACHE_USED 1
5175#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
5176#define SQLITE_STATUS_SCRATCH_USED 3
5177#define SQLITE_STATUS_SCRATCH_OVERFLOW 4
5178#define SQLITE_STATUS_MALLOC_SIZE 5
drhec424a52008-07-25 15:39:03 +00005179#define SQLITE_STATUS_PARSER_STACK 6
drhe50135e2008-08-05 17:53:22 +00005180#define SQLITE_STATUS_PAGECACHE_SIZE 7
5181#define SQLITE_STATUS_SCRATCH_SIZE 8
drhf7141992008-06-19 00:16:08 +00005182
drh633e6d52008-07-28 19:34:53 +00005183/*
drhd68eee02009-12-11 03:44:18 +00005184** CAPI3REF: Database Connection Status
drhd1d38482008-10-07 23:46:38 +00005185**
drhd68eee02009-12-11 03:44:18 +00005186** ^This interface is used to retrieve runtime status information
5187** about a single [database connection]. ^The first argument is the
5188** database connection object to be interrogated. ^The second argument
drh63da0892010-03-10 21:42:07 +00005189** is an integer constant, taken from the set of
5190** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros, that
5191** determiness the parameter to interrogate. The set of
5192** [SQLITE_DBSTATUS_LOOKASIDE_USED | SQLITE_DBSTATUS_*] macros is likely
5193** to grow in future releases of SQLite.
drhd1d38482008-10-07 23:46:38 +00005194**
drhd68eee02009-12-11 03:44:18 +00005195** ^The current value of the requested parameter is written into *pCur
5196** and the highest instantaneous value is written into *pHiwtr. ^If
drhd1d38482008-10-07 23:46:38 +00005197** the resetFlg is true, then the highest instantaneous value is
5198** reset back down to the current value.
5199**
5200** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
5201*/
drh9f8da322010-03-10 20:06:37 +00005202int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
drhd1d38482008-10-07 23:46:38 +00005203
5204/*
drhd68eee02009-12-11 03:44:18 +00005205** CAPI3REF: Status Parameters for database connections
drh633e6d52008-07-28 19:34:53 +00005206**
drh6aa5f152009-08-19 15:57:07 +00005207** These constants are the available integer "verbs" that can be passed as
5208** the second argument to the [sqlite3_db_status()] interface.
5209**
5210** New verbs may be added in future releases of SQLite. Existing verbs
5211** might be discontinued. Applications should check the return code from
5212** [sqlite3_db_status()] to make sure that the call worked.
5213** The [sqlite3_db_status()] interface will return a non-zero error code
5214** if a discontinued or unsupported verb is invoked.
drh633e6d52008-07-28 19:34:53 +00005215**
5216** <dl>
drhd68eee02009-12-11 03:44:18 +00005217** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
drh633e6d52008-07-28 19:34:53 +00005218** <dd>This parameter returns the number of lookaside memory slots currently
drhd68eee02009-12-11 03:44:18 +00005219** checked out.</dd>)^
drh63da0892010-03-10 21:42:07 +00005220**
5221** <dt>SQLITE_DBSTATUS_CACHE_USED</dt>
5222** <dd>^This parameter returns the approximate number of of bytes of heap
5223** memory used by all pager caches associated with the database connection.
5224** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
5225** checked out.</dd>)^
drh633e6d52008-07-28 19:34:53 +00005226** </dl>
5227*/
5228#define SQLITE_DBSTATUS_LOOKASIDE_USED 0
drh63da0892010-03-10 21:42:07 +00005229#define SQLITE_DBSTATUS_CACHE_USED 1
5230#define SQLITE_DBSTATUS_MAX 1 /* Largest defined DBSTATUS */
drhed13d982008-01-31 14:43:24 +00005231
drhd1d38482008-10-07 23:46:38 +00005232
5233/*
drhd68eee02009-12-11 03:44:18 +00005234** CAPI3REF: Prepared Statement Status
drhd1d38482008-10-07 23:46:38 +00005235**
drhd68eee02009-12-11 03:44:18 +00005236** ^(Each prepared statement maintains various
drhd1d38482008-10-07 23:46:38 +00005237** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
drh9be37f62009-12-12 23:57:36 +00005238** of times it has performed specific operations.)^ These counters can
drhd1d38482008-10-07 23:46:38 +00005239** be used to monitor the performance characteristics of the prepared
5240** statements. For example, if the number of table steps greatly exceeds
5241** the number of table searches or result rows, that would tend to indicate
5242** that the prepared statement is using a full table scan rather than
5243** an index.
5244**
drhd68eee02009-12-11 03:44:18 +00005245** ^(This interface is used to retrieve and reset counter values from
drhd1d38482008-10-07 23:46:38 +00005246** a [prepared statement]. The first argument is the prepared statement
5247** object to be interrogated. The second argument
5248** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
drhd68eee02009-12-11 03:44:18 +00005249** to be interrogated.)^
5250** ^The current value of the requested counter is returned.
5251** ^If the resetFlg is true, then the counter is reset to zero after this
drhd1d38482008-10-07 23:46:38 +00005252** interface call returns.
5253**
5254** See also: [sqlite3_status()] and [sqlite3_db_status()].
5255*/
drh9f8da322010-03-10 20:06:37 +00005256int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
drhd1d38482008-10-07 23:46:38 +00005257
5258/*
drhd68eee02009-12-11 03:44:18 +00005259** CAPI3REF: Status Parameters for prepared statements
drhd1d38482008-10-07 23:46:38 +00005260**
5261** These preprocessor macros define integer codes that name counter
5262** values associated with the [sqlite3_stmt_status()] interface.
5263** The meanings of the various counters are as follows:
5264**
5265** <dl>
5266** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
drhd68eee02009-12-11 03:44:18 +00005267** <dd>^This is the number of times that SQLite has stepped forward in
drhd1d38482008-10-07 23:46:38 +00005268** a table as part of a full table scan. Large numbers for this counter
5269** may indicate opportunities for performance improvement through
5270** careful use of indices.</dd>
5271**
5272** <dt>SQLITE_STMTSTATUS_SORT</dt>
drhd68eee02009-12-11 03:44:18 +00005273** <dd>^This is the number of sort operations that have occurred.
drhd1d38482008-10-07 23:46:38 +00005274** A non-zero value in this counter may indicate an opportunity to
5275** improvement performance through careful use of indices.</dd>
5276**
drha21a64d2010-04-06 22:33:55 +00005277** <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
5278** <dd>^This is the number of rows inserted into transient indices that
5279** were created automatically in order to help joins run faster.
5280** A non-zero value in this counter may indicate an opportunity to
5281** improvement performance by adding permanent indices that do not
5282** need to be reinitialized each time the statement is run.</dd>
5283**
drhd1d38482008-10-07 23:46:38 +00005284** </dl>
5285*/
5286#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
5287#define SQLITE_STMTSTATUS_SORT 2
drha21a64d2010-04-06 22:33:55 +00005288#define SQLITE_STMTSTATUS_AUTOINDEX 3
drhd1d38482008-10-07 23:46:38 +00005289
drhed13d982008-01-31 14:43:24 +00005290/*
drh21614742008-11-18 19:18:08 +00005291** CAPI3REF: Custom Page Cache Object
drh21614742008-11-18 19:18:08 +00005292**
danielk1977bc2ca9e2008-11-13 14:28:28 +00005293** The sqlite3_pcache type is opaque. It is implemented by
5294** the pluggable module. The SQLite core has no knowledge of
5295** its size or internal structure and never deals with the
5296** sqlite3_pcache object except by holding and passing pointers
5297** to the object.
drh21614742008-11-18 19:18:08 +00005298**
5299** See [sqlite3_pcache_methods] for additional information.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005300*/
5301typedef struct sqlite3_pcache sqlite3_pcache;
5302
5303/*
drh21614742008-11-18 19:18:08 +00005304** CAPI3REF: Application Defined Page Cache.
drh67fba282009-08-26 00:26:51 +00005305** KEYWORDS: {page cache}
danielk1977bc2ca9e2008-11-13 14:28:28 +00005306**
drhd68eee02009-12-11 03:44:18 +00005307** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE], ...) interface can
danielk1977bc2ca9e2008-11-13 14:28:28 +00005308** register an alternative page cache implementation by passing in an
drhdf6473a2009-12-13 22:20:08 +00005309** instance of the sqlite3_pcache_methods structure.)^ The majority of the
shane7c7c3112009-08-17 15:31:23 +00005310** heap memory used by SQLite is used by the page cache to cache data read
danielk1977bc2ca9e2008-11-13 14:28:28 +00005311** from, or ready to be written to, the database file. By implementing a
5312** custom page cache using this API, an application can control more
shane7c7c3112009-08-17 15:31:23 +00005313** precisely the amount of memory consumed by SQLite, the way in which
drh67fba282009-08-26 00:26:51 +00005314** that memory is allocated and released, and the policies used to
danielk1977bc2ca9e2008-11-13 14:28:28 +00005315** determine exactly which parts of a database file are cached and for
5316** how long.
5317**
drhd68eee02009-12-11 03:44:18 +00005318** ^(The contents of the sqlite3_pcache_methods structure are copied to an
drh67fba282009-08-26 00:26:51 +00005319** internal buffer by SQLite within the call to [sqlite3_config]. Hence
5320** the application may discard the parameter after the call to
drhd68eee02009-12-11 03:44:18 +00005321** [sqlite3_config()] returns.)^
danielk1977bc2ca9e2008-11-13 14:28:28 +00005322**
drhd68eee02009-12-11 03:44:18 +00005323** ^The xInit() method is called once for each call to [sqlite3_initialize()]
drh9be37f62009-12-12 23:57:36 +00005324** (usually only once during the lifetime of the process). ^(The xInit()
5325** method is passed a copy of the sqlite3_pcache_methods.pArg value.)^
5326** ^The xInit() method can set up up global structures and/or any mutexes
5327** required by the custom page cache implementation.
shane7c7c3112009-08-17 15:31:23 +00005328**
drhd68eee02009-12-11 03:44:18 +00005329** ^The xShutdown() method is called from within [sqlite3_shutdown()],
shane7c7c3112009-08-17 15:31:23 +00005330** if the application invokes this API. It can be used to clean up
5331** any outstanding resources before process shutdown, if required.
5332**
drhd68eee02009-12-11 03:44:18 +00005333** ^SQLite holds a [SQLITE_MUTEX_RECURSIVE] mutex when it invokes
5334** the xInit method, so the xInit method need not be threadsafe. ^The
shane7c7c3112009-08-17 15:31:23 +00005335** xShutdown method is only called from [sqlite3_shutdown()] so it does
5336** not need to be threadsafe either. All other methods must be threadsafe
5337** in multithreaded applications.
5338**
drhd68eee02009-12-11 03:44:18 +00005339** ^SQLite will never invoke xInit() more than once without an intervening
shane7c7c3112009-08-17 15:31:23 +00005340** call to xShutdown().
danielk1977bc2ca9e2008-11-13 14:28:28 +00005341**
drhd68eee02009-12-11 03:44:18 +00005342** ^The xCreate() method is used to construct a new cache instance. SQLite
drh67fba282009-08-26 00:26:51 +00005343** will typically create one cache instance for each open database file,
drhd68eee02009-12-11 03:44:18 +00005344** though this is not guaranteed. ^The
danielk1977bc2ca9e2008-11-13 14:28:28 +00005345** first parameter, szPage, is the size in bytes of the pages that must
drhd68eee02009-12-11 03:44:18 +00005346** be allocated by the cache. ^szPage will not be a power of two. ^szPage
drh67fba282009-08-26 00:26:51 +00005347** will the page size of the database file that is to be cached plus an
drhd68eee02009-12-11 03:44:18 +00005348** increment (here called "R") of about 100 or 200. ^SQLite will use the
drh67fba282009-08-26 00:26:51 +00005349** extra R bytes on each page to store metadata about the underlying
5350** database page on disk. The value of R depends
5351** on the SQLite version, the target platform, and how SQLite was compiled.
drhd68eee02009-12-11 03:44:18 +00005352** ^R is constant for a particular build of SQLite. ^The second argument to
drh67fba282009-08-26 00:26:51 +00005353** xCreate(), bPurgeable, is true if the cache being created will
5354** be used to cache database pages of a file stored on disk, or
drhd68eee02009-12-11 03:44:18 +00005355** false if it is used for an in-memory database. ^The cache implementation
drh67fba282009-08-26 00:26:51 +00005356** does not have to do anything special based with the value of bPurgeable;
drhd68eee02009-12-11 03:44:18 +00005357** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
drh67fba282009-08-26 00:26:51 +00005358** never invoke xUnpin() except to deliberately delete a page.
drhd68eee02009-12-11 03:44:18 +00005359** ^In other words, a cache created with bPurgeable set to false will
drh67fba282009-08-26 00:26:51 +00005360** never contain any unpinned pages.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005361**
drhd68eee02009-12-11 03:44:18 +00005362** ^(The xCachesize() method may be called at any time by SQLite to set the
danielk1977bc2ca9e2008-11-13 14:28:28 +00005363** suggested maximum cache-size (number of pages stored by) the cache
5364** instance passed as the first argument. This is the value configured using
drh7a98b852009-12-13 23:03:01 +00005365** the SQLite "[PRAGMA cache_size]" command.)^ ^As with the bPurgeable
5366** parameter, the implementation is not required to do anything with this
drh67fba282009-08-26 00:26:51 +00005367** value; it is advisory only.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005368**
drhd68eee02009-12-11 03:44:18 +00005369** ^The xPagecount() method should return the number of pages currently
drh67fba282009-08-26 00:26:51 +00005370** stored in the cache.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005371**
drh7a98b852009-12-13 23:03:01 +00005372** ^The xFetch() method is used to fetch a page and return a pointer to it.
5373** ^A 'page', in this context, is a buffer of szPage bytes aligned at an
5374** 8-byte boundary. ^The page to be fetched is determined by the key. ^The
danielk1977bc2ca9e2008-11-13 14:28:28 +00005375** mimimum key value is 1. After it has been retrieved using xFetch, the page
drh67fba282009-08-26 00:26:51 +00005376** is considered to be "pinned".
danielk1977bc2ca9e2008-11-13 14:28:28 +00005377**
drhd68eee02009-12-11 03:44:18 +00005378** ^If the requested page is already in the page cache, then the page cache
drh67fba282009-08-26 00:26:51 +00005379** implementation must return a pointer to the page buffer with its content
drhd68eee02009-12-11 03:44:18 +00005380** intact. ^(If the requested page is not already in the cache, then the
drh67fba282009-08-26 00:26:51 +00005381** behavior of the cache implementation is determined by the value of the
5382** createFlag parameter passed to xFetch, according to the following table:
danielk1977bc2ca9e2008-11-13 14:28:28 +00005383**
5384** <table border=1 width=85% align=center>
drh67fba282009-08-26 00:26:51 +00005385** <tr><th> createFlag <th> Behaviour when page is not already in cache
5386** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
5387** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
5388** Otherwise return NULL.
5389** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
5390** NULL if allocating a new page is effectively impossible.
drhd68eee02009-12-11 03:44:18 +00005391** </table>)^
danielk1977bc2ca9e2008-11-13 14:28:28 +00005392**
drh67fba282009-08-26 00:26:51 +00005393** SQLite will normally invoke xFetch() with a createFlag of 0 or 1. If
5394** a call to xFetch() with createFlag==1 returns NULL, then SQLite will
5395** attempt to unpin one or more cache pages by spilling the content of
5396** pinned pages to disk and synching the operating system disk cache. After
5397** attempting to unpin pages, the xFetch() method will be invoked again with
5398** a createFlag of 2.
5399**
drhd68eee02009-12-11 03:44:18 +00005400** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
5401** as its second argument. ^(If the third parameter, discard, is non-zero,
danielk1977bc2ca9e2008-11-13 14:28:28 +00005402** then the page should be evicted from the cache. In this case SQLite
5403** assumes that the next time the page is retrieved from the cache using
drhd68eee02009-12-11 03:44:18 +00005404** the xFetch() method, it will be zeroed.)^ ^If the discard parameter is
5405** zero, then the page is considered to be unpinned. ^The cache implementation
drh67fba282009-08-26 00:26:51 +00005406** may choose to evict unpinned pages at any time.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005407**
drhd68eee02009-12-11 03:44:18 +00005408** ^(The cache is not required to perform any reference counting. A single
danielk1977bc2ca9e2008-11-13 14:28:28 +00005409** call to xUnpin() unpins the page regardless of the number of prior calls
drhd68eee02009-12-11 03:44:18 +00005410** to xFetch().)^
danielk1977bc2ca9e2008-11-13 14:28:28 +00005411**
drhd68eee02009-12-11 03:44:18 +00005412** ^The xRekey() method is used to change the key value associated with the
5413** page passed as the second argument from oldKey to newKey. ^If the cache
drhb232c232008-11-19 01:20:26 +00005414** previously contains an entry associated with newKey, it should be
drhd68eee02009-12-11 03:44:18 +00005415** discarded. ^Any prior cache entry associated with newKey is guaranteed not
drhb232c232008-11-19 01:20:26 +00005416** to be pinned.
danielk1977bc2ca9e2008-11-13 14:28:28 +00005417**
drhd68eee02009-12-11 03:44:18 +00005418** ^When SQLite calls the xTruncate() method, the cache must discard all
danielk1977bc2ca9e2008-11-13 14:28:28 +00005419** existing cache entries with page numbers (keys) greater than or equal
drhd68eee02009-12-11 03:44:18 +00005420** to the value of the iLimit parameter passed to xTruncate(). ^If any
danielk1977bc2ca9e2008-11-13 14:28:28 +00005421** of these pages are pinned, they are implicitly unpinned, meaning that
5422** they can be safely discarded.
5423**
drhd68eee02009-12-11 03:44:18 +00005424** ^The xDestroy() method is used to delete a cache allocated by xCreate().
5425** All resources associated with the specified cache should be freed. ^After
drh21614742008-11-18 19:18:08 +00005426** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
danielk1977bc2ca9e2008-11-13 14:28:28 +00005427** handle invalid, and will not use it with any other sqlite3_pcache_methods
5428** functions.
5429*/
5430typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
5431struct sqlite3_pcache_methods {
5432 void *pArg;
5433 int (*xInit)(void*);
5434 void (*xShutdown)(void*);
5435 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
5436 void (*xCachesize)(sqlite3_pcache*, int nCachesize);
5437 int (*xPagecount)(sqlite3_pcache*);
5438 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
5439 void (*xUnpin)(sqlite3_pcache*, void*, int discard);
5440 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
5441 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
5442 void (*xDestroy)(sqlite3_pcache*);
5443};
5444
5445/*
drh27b3b842009-02-03 18:25:13 +00005446** CAPI3REF: Online Backup Object
drh27b3b842009-02-03 18:25:13 +00005447**
5448** The sqlite3_backup object records state information about an ongoing
drhd68eee02009-12-11 03:44:18 +00005449** online backup operation. ^The sqlite3_backup object is created by
drh27b3b842009-02-03 18:25:13 +00005450** a call to [sqlite3_backup_init()] and is destroyed by a call to
5451** [sqlite3_backup_finish()].
drh52224a72009-02-10 13:41:42 +00005452**
5453** See Also: [Using the SQLite Online Backup API]
drh27b3b842009-02-03 18:25:13 +00005454*/
5455typedef struct sqlite3_backup sqlite3_backup;
5456
5457/*
danielk197704103022009-02-03 16:51:24 +00005458** CAPI3REF: Online Backup API.
danielk197704103022009-02-03 16:51:24 +00005459**
drhd68eee02009-12-11 03:44:18 +00005460** The backup API copies the content of one database into another.
5461** It is useful either for creating backups of databases or
danielk197704103022009-02-03 16:51:24 +00005462** for copying in-memory databases to or from persistent files.
5463**
drh52224a72009-02-10 13:41:42 +00005464** See Also: [Using the SQLite Online Backup API]
5465**
drhd68eee02009-12-11 03:44:18 +00005466** ^Exclusive access is required to the destination database for the
5467** duration of the operation. ^However the source database is only
5468** read-locked while it is actually being read; it is not locked
5469** continuously for the entire backup operation. ^Thus, the backup may be
5470** performed on a live source database without preventing other users from
drhdf6473a2009-12-13 22:20:08 +00005471** reading or writing to the source database while the backup is underway.
danielk197704103022009-02-03 16:51:24 +00005472**
drhd68eee02009-12-11 03:44:18 +00005473** ^(To perform a backup operation:
danielk197704103022009-02-03 16:51:24 +00005474** <ol>
drh62b5d2d2009-02-03 18:47:22 +00005475** <li><b>sqlite3_backup_init()</b> is called once to initialize the
5476** backup,
5477** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
danielk197704103022009-02-03 16:51:24 +00005478** the data between the two databases, and finally
drh62b5d2d2009-02-03 18:47:22 +00005479** <li><b>sqlite3_backup_finish()</b> is called to release all resources
danielk197704103022009-02-03 16:51:24 +00005480** associated with the backup operation.
drhd68eee02009-12-11 03:44:18 +00005481** </ol>)^
danielk197704103022009-02-03 16:51:24 +00005482** There should be exactly one call to sqlite3_backup_finish() for each
5483** successful call to sqlite3_backup_init().
5484**
5485** <b>sqlite3_backup_init()</b>
5486**
drhd68eee02009-12-11 03:44:18 +00005487** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
5488** [database connection] associated with the destination database
5489** and the database name, respectively.
5490** ^The database name is "main" for the main database, "temp" for the
5491** temporary database, or the name specified after the AS keyword in
5492** an [ATTACH] statement for an attached database.
5493** ^The S and M arguments passed to
5494** sqlite3_backup_init(D,N,S,M) identify the [database connection]
5495** and database name of the source database, respectively.
5496** ^The source and destination [database connections] (parameters S and D)
5497** must be different or else sqlite3_backup_init(D,N,S,M) will file with
5498** an error.
danielk197704103022009-02-03 16:51:24 +00005499**
drhd68eee02009-12-11 03:44:18 +00005500** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
5501** returned and an error code and error message are store3d in the
5502** destination [database connection] D.
5503** ^The error code and message for the failed call to sqlite3_backup_init()
5504** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
5505** [sqlite3_errmsg16()] functions.
5506** ^A successful call to sqlite3_backup_init() returns a pointer to an
5507** [sqlite3_backup] object.
5508** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
danielk197704103022009-02-03 16:51:24 +00005509** sqlite3_backup_finish() functions to perform the specified backup
5510** operation.
5511**
5512** <b>sqlite3_backup_step()</b>
5513**
drhd68eee02009-12-11 03:44:18 +00005514** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
5515** the source and destination databases specified by [sqlite3_backup] object B.
drh9be37f62009-12-12 23:57:36 +00005516** ^If N is negative, all remaining source pages are copied.
drhd68eee02009-12-11 03:44:18 +00005517** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
5518** are still more pages to be copied, then the function resturns [SQLITE_OK].
5519** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
5520** from source to destination, then it returns [SQLITE_DONE].
5521** ^If an error occurs while running sqlite3_backup_step(B,N),
5522** then an [error code] is returned. ^As well as [SQLITE_OK] and
drh62b5d2d2009-02-03 18:47:22 +00005523** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
5524** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
5525** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
danielk197704103022009-02-03 16:51:24 +00005526**
drh3289c5e2010-05-05 16:23:26 +00005527** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
5528** <ol>
5529** <li> the destination database was opened read-only, or
5530** <li> the destination database is using write-ahead-log journaling
5531** and the destination and source page sizes differ, or
5532** <li> The destination database is an in-memory database and the
5533** destination and source page sizes differ.
5534** </ol>)^
danielk197704103022009-02-03 16:51:24 +00005535**
drhd68eee02009-12-11 03:44:18 +00005536** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
drh62b5d2d2009-02-03 18:47:22 +00005537** the [sqlite3_busy_handler | busy-handler function]
drhd68eee02009-12-11 03:44:18 +00005538** is invoked (if one is specified). ^If the
danielk197704103022009-02-03 16:51:24 +00005539** busy-handler returns non-zero before the lock is available, then
drhd68eee02009-12-11 03:44:18 +00005540** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
5541** sqlite3_backup_step() can be retried later. ^If the source
drh62b5d2d2009-02-03 18:47:22 +00005542** [database connection]
danielk197704103022009-02-03 16:51:24 +00005543** is being used to write to the source database when sqlite3_backup_step()
drhd68eee02009-12-11 03:44:18 +00005544** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
5545** case the call to sqlite3_backup_step() can be retried later on. ^(If
drh62b5d2d2009-02-03 18:47:22 +00005546** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
5547** [SQLITE_READONLY] is returned, then
danielk197704103022009-02-03 16:51:24 +00005548** there is no point in retrying the call to sqlite3_backup_step(). These
drhd68eee02009-12-11 03:44:18 +00005549** errors are considered fatal.)^ The application must accept
danielk197704103022009-02-03 16:51:24 +00005550** that the backup operation has failed and pass the backup operation handle
5551** to the sqlite3_backup_finish() to release associated resources.
5552**
drhd68eee02009-12-11 03:44:18 +00005553** ^The first call to sqlite3_backup_step() obtains an exclusive lock
5554** on the destination file. ^The exclusive lock is not released until either
danielk197704103022009-02-03 16:51:24 +00005555** sqlite3_backup_finish() is called or the backup operation is complete
drhd68eee02009-12-11 03:44:18 +00005556** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
5557** sqlite3_backup_step() obtains a [shared lock] on the source database that
5558** lasts for the duration of the sqlite3_backup_step() call.
5559** ^Because the source database is not locked between calls to
5560** sqlite3_backup_step(), the source database may be modified mid-way
5561** through the backup process. ^If the source database is modified by an
danielk197704103022009-02-03 16:51:24 +00005562** external process or via a database connection other than the one being
drhd68eee02009-12-11 03:44:18 +00005563** used by the backup operation, then the backup will be automatically
5564** restarted by the next call to sqlite3_backup_step(). ^If the source
danielk197704103022009-02-03 16:51:24 +00005565** database is modified by the using the same database connection as is used
drhd68eee02009-12-11 03:44:18 +00005566** by the backup operation, then the backup database is automatically
danielk197704103022009-02-03 16:51:24 +00005567** updated at the same time.
5568**
5569** <b>sqlite3_backup_finish()</b>
5570**
drhd68eee02009-12-11 03:44:18 +00005571** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
5572** application wishes to abandon the backup operation, the application
5573** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
5574** ^The sqlite3_backup_finish() interfaces releases all
5575** resources associated with the [sqlite3_backup] object.
5576** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
5577** active write-transaction on the destination database is rolled back.
5578** The [sqlite3_backup] object is invalid
danielk197704103022009-02-03 16:51:24 +00005579** and may not be used following a call to sqlite3_backup_finish().
5580**
drhd68eee02009-12-11 03:44:18 +00005581** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
5582** sqlite3_backup_step() errors occurred, regardless or whether or not
5583** sqlite3_backup_step() completed.
5584** ^If an out-of-memory condition or IO error occurred during any prior
5585** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
5586** sqlite3_backup_finish() returns the corresponding [error code].
danielk197704103022009-02-03 16:51:24 +00005587**
drhd68eee02009-12-11 03:44:18 +00005588** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
5589** is not a permanent error and does not affect the return value of
danielk197704103022009-02-03 16:51:24 +00005590** sqlite3_backup_finish().
5591**
5592** <b>sqlite3_backup_remaining(), sqlite3_backup_pagecount()</b>
5593**
drhd68eee02009-12-11 03:44:18 +00005594** ^Each call to sqlite3_backup_step() sets two values inside
5595** the [sqlite3_backup] object: the number of pages still to be backed
5596** up and the total number of pages in the source databae file.
5597** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
5598** retrieve these two values, respectively.
danielk197704103022009-02-03 16:51:24 +00005599**
drhd68eee02009-12-11 03:44:18 +00005600** ^The values returned by these functions are only updated by
5601** sqlite3_backup_step(). ^If the source database is modified during a backup
danielk197704103022009-02-03 16:51:24 +00005602** operation, then the values are not updated to account for any extra
5603** pages that need to be updated or the size of the source database file
5604** changing.
5605**
5606** <b>Concurrent Usage of Database Handles</b>
5607**
drhd68eee02009-12-11 03:44:18 +00005608** ^The source [database connection] may be used by the application for other
danielk197704103022009-02-03 16:51:24 +00005609** purposes while a backup operation is underway or being initialized.
drhd68eee02009-12-11 03:44:18 +00005610** ^If SQLite is compiled and configured to support threadsafe database
danielk197704103022009-02-03 16:51:24 +00005611** connections, then the source database connection may be used concurrently
5612** from within other threads.
5613**
drhd68eee02009-12-11 03:44:18 +00005614** However, the application must guarantee that the destination
5615** [database connection] is not passed to any other API (by any thread) after
danielk197704103022009-02-03 16:51:24 +00005616** sqlite3_backup_init() is called and before the corresponding call to
drhd68eee02009-12-11 03:44:18 +00005617** sqlite3_backup_finish(). SQLite does not currently check to see
5618** if the application incorrectly accesses the destination [database connection]
5619** and so no error code is reported, but the operations may malfunction
5620** nevertheless. Use of the destination database connection while a
5621** backup is in progress might also also cause a mutex deadlock.
danielk197704103022009-02-03 16:51:24 +00005622**
drhd68eee02009-12-11 03:44:18 +00005623** If running in [shared cache mode], the application must
danielk197704103022009-02-03 16:51:24 +00005624** guarantee that the shared cache used by the destination database
5625** is not accessed while the backup is running. In practice this means
drhd68eee02009-12-11 03:44:18 +00005626** that the application must guarantee that the disk file being
danielk197704103022009-02-03 16:51:24 +00005627** backed up to is not accessed by any connection within the process,
5628** not just the specific connection that was passed to sqlite3_backup_init().
5629**
drh27b3b842009-02-03 18:25:13 +00005630** The [sqlite3_backup] object itself is partially threadsafe. Multiple
danielk197704103022009-02-03 16:51:24 +00005631** threads may safely make multiple concurrent calls to sqlite3_backup_step().
5632** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
5633** APIs are not strictly speaking threadsafe. If they are invoked at the
5634** same time as another thread is invoking sqlite3_backup_step() it is
5635** possible that they return invalid values.
5636*/
danielk197704103022009-02-03 16:51:24 +00005637sqlite3_backup *sqlite3_backup_init(
5638 sqlite3 *pDest, /* Destination database handle */
5639 const char *zDestName, /* Destination database name */
5640 sqlite3 *pSource, /* Source database handle */
5641 const char *zSourceName /* Source database name */
5642);
5643int sqlite3_backup_step(sqlite3_backup *p, int nPage);
5644int sqlite3_backup_finish(sqlite3_backup *p);
5645int sqlite3_backup_remaining(sqlite3_backup *p);
5646int sqlite3_backup_pagecount(sqlite3_backup *p);
5647
5648/*
danielk1977404ca072009-03-16 13:19:36 +00005649** CAPI3REF: Unlock Notification
danielk1977404ca072009-03-16 13:19:36 +00005650**
drhd68eee02009-12-11 03:44:18 +00005651** ^When running in shared-cache mode, a database operation may fail with
drh89487472009-03-16 13:37:02 +00005652** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
danielk1977404ca072009-03-16 13:19:36 +00005653** individual tables within the shared-cache cannot be obtained. See
5654** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
drhd68eee02009-12-11 03:44:18 +00005655** ^This API may be used to register a callback that SQLite will invoke
danielk1977404ca072009-03-16 13:19:36 +00005656** when the connection currently holding the required lock relinquishes it.
drhd68eee02009-12-11 03:44:18 +00005657** ^This API is only available if the library was compiled with the
drh89487472009-03-16 13:37:02 +00005658** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
danielk1977404ca072009-03-16 13:19:36 +00005659**
5660** See Also: [Using the SQLite Unlock Notification Feature].
5661**
drhd68eee02009-12-11 03:44:18 +00005662** ^Shared-cache locks are released when a database connection concludes
danielk1977404ca072009-03-16 13:19:36 +00005663** its current transaction, either by committing it or rolling it back.
5664**
drhd68eee02009-12-11 03:44:18 +00005665** ^When a connection (known as the blocked connection) fails to obtain a
danielk1977404ca072009-03-16 13:19:36 +00005666** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
5667** identity of the database connection (the blocking connection) that
drhd68eee02009-12-11 03:44:18 +00005668** has locked the required resource is stored internally. ^After an
danielk1977404ca072009-03-16 13:19:36 +00005669** application receives an SQLITE_LOCKED error, it may call the
5670** sqlite3_unlock_notify() method with the blocked connection handle as
5671** the first argument to register for a callback that will be invoked
drhd68eee02009-12-11 03:44:18 +00005672** when the blocking connections current transaction is concluded. ^The
danielk1977404ca072009-03-16 13:19:36 +00005673** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
5674** call that concludes the blocking connections transaction.
5675**
drhd68eee02009-12-11 03:44:18 +00005676** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
danielk1977404ca072009-03-16 13:19:36 +00005677** there is a chance that the blocking connection will have already
5678** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
5679** If this happens, then the specified callback is invoked immediately,
drhd68eee02009-12-11 03:44:18 +00005680** from within the call to sqlite3_unlock_notify().)^
danielk1977404ca072009-03-16 13:19:36 +00005681**
drhd68eee02009-12-11 03:44:18 +00005682** ^If the blocked connection is attempting to obtain a write-lock on a
danielk1977404ca072009-03-16 13:19:36 +00005683** shared-cache table, and more than one other connection currently holds
5684** a read-lock on the same table, then SQLite arbitrarily selects one of
5685** the other connections to use as the blocking connection.
5686**
drhd68eee02009-12-11 03:44:18 +00005687** ^(There may be at most one unlock-notify callback registered by a
danielk1977404ca072009-03-16 13:19:36 +00005688** blocked connection. If sqlite3_unlock_notify() is called when the
5689** blocked connection already has a registered unlock-notify callback,
drh7a98b852009-12-13 23:03:01 +00005690** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
danielk1977404ca072009-03-16 13:19:36 +00005691** called with a NULL pointer as its second argument, then any existing
drhd68eee02009-12-11 03:44:18 +00005692** unlock-notify callback is cancelled. ^The blocked connections
danielk1977404ca072009-03-16 13:19:36 +00005693** unlock-notify callback may also be canceled by closing the blocked
5694** connection using [sqlite3_close()].
5695**
5696** The unlock-notify callback is not reentrant. If an application invokes
5697** any sqlite3_xxx API functions from within an unlock-notify callback, a
5698** crash or deadlock may be the result.
5699**
drhd68eee02009-12-11 03:44:18 +00005700** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
danielk1977404ca072009-03-16 13:19:36 +00005701** returns SQLITE_OK.
5702**
5703** <b>Callback Invocation Details</b>
5704**
5705** When an unlock-notify callback is registered, the application provides a
5706** single void* pointer that is passed to the callback when it is invoked.
5707** However, the signature of the callback function allows SQLite to pass
5708** it an array of void* context pointers. The first argument passed to
5709** an unlock-notify callback is a pointer to an array of void* pointers,
5710** and the second is the number of entries in the array.
5711**
5712** When a blocking connections transaction is concluded, there may be
5713** more than one blocked connection that has registered for an unlock-notify
drhd68eee02009-12-11 03:44:18 +00005714** callback. ^If two or more such blocked connections have specified the
danielk1977404ca072009-03-16 13:19:36 +00005715** same callback function, then instead of invoking the callback function
5716** multiple times, it is invoked once with the set of void* context pointers
5717** specified by the blocked connections bundled together into an array.
5718** This gives the application an opportunity to prioritize any actions
5719** related to the set of unblocked database connections.
5720**
5721** <b>Deadlock Detection</b>
5722**
5723** Assuming that after registering for an unlock-notify callback a
5724** database waits for the callback to be issued before taking any further
5725** action (a reasonable assumption), then using this API may cause the
5726** application to deadlock. For example, if connection X is waiting for
5727** connection Y's transaction to be concluded, and similarly connection
5728** Y is waiting on connection X's transaction, then neither connection
5729** will proceed and the system may remain deadlocked indefinitely.
5730**
5731** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
drhd68eee02009-12-11 03:44:18 +00005732** detection. ^If a given call to sqlite3_unlock_notify() would put the
danielk1977404ca072009-03-16 13:19:36 +00005733** system in a deadlocked state, then SQLITE_LOCKED is returned and no
5734** unlock-notify callback is registered. The system is said to be in
5735** a deadlocked state if connection A has registered for an unlock-notify
5736** callback on the conclusion of connection B's transaction, and connection
5737** B has itself registered for an unlock-notify callback when connection
drhd68eee02009-12-11 03:44:18 +00005738** A's transaction is concluded. ^Indirect deadlock is also detected, so
danielk1977404ca072009-03-16 13:19:36 +00005739** the system is also considered to be deadlocked if connection B has
5740** registered for an unlock-notify callback on the conclusion of connection
drhd68eee02009-12-11 03:44:18 +00005741** C's transaction, where connection C is waiting on connection A. ^Any
danielk1977404ca072009-03-16 13:19:36 +00005742** number of levels of indirection are allowed.
5743**
5744** <b>The "DROP TABLE" Exception</b>
5745**
5746** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
5747** always appropriate to call sqlite3_unlock_notify(). There is however,
5748** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
5749** SQLite checks if there are any currently executing SELECT statements
5750** that belong to the same connection. If there are, SQLITE_LOCKED is
5751** returned. In this case there is no "blocking connection", so invoking
5752** sqlite3_unlock_notify() results in the unlock-notify callback being
5753** invoked immediately. If the application then re-attempts the "DROP TABLE"
5754** or "DROP INDEX" query, an infinite loop might be the result.
5755**
5756** One way around this problem is to check the extended error code returned
drhd68eee02009-12-11 03:44:18 +00005757** by an sqlite3_step() call. ^(If there is a blocking connection, then the
danielk1977404ca072009-03-16 13:19:36 +00005758** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
5759** the special "DROP TABLE/INDEX" case, the extended error code is just
drhd68eee02009-12-11 03:44:18 +00005760** SQLITE_LOCKED.)^
danielk1977404ca072009-03-16 13:19:36 +00005761*/
5762int sqlite3_unlock_notify(
5763 sqlite3 *pBlocked, /* Waiting connection */
5764 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
5765 void *pNotifyArg /* Argument to pass to xNotify */
5766);
5767
danielk1977ee0484c2009-07-28 16:44:26 +00005768
5769/*
5770** CAPI3REF: String Comparison
danielk1977ee0484c2009-07-28 16:44:26 +00005771**
drhd68eee02009-12-11 03:44:18 +00005772** ^The [sqlite3_strnicmp()] API allows applications and extensions to
danielk1977ee0484c2009-07-28 16:44:26 +00005773** compare the contents of two buffers containing UTF-8 strings in a
5774** case-indendent fashion, using the same definition of case independence
5775** that SQLite uses internally when comparing identifiers.
5776*/
5777int sqlite3_strnicmp(const char *, const char *, int);
5778
danielk1977404ca072009-03-16 13:19:36 +00005779/*
drh3f280702010-02-18 18:45:09 +00005780** CAPI3REF: Error Logging Interface
drh3f280702010-02-18 18:45:09 +00005781**
5782** ^The [sqlite3_log()] interface writes a message into the error log
drh71caabf2010-02-26 15:39:24 +00005783** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
drhbee80652010-02-25 21:27:58 +00005784** ^If logging is enabled, the zFormat string and subsequent arguments are
drhd3d986d2010-03-31 13:57:56 +00005785** used with [sqlite3_snprintf()] to generate the final output string.
drh3f280702010-02-18 18:45:09 +00005786**
5787** The sqlite3_log() interface is intended for use by extensions such as
5788** virtual tables, collating functions, and SQL functions. While there is
5789** nothing to prevent an application from calling sqlite3_log(), doing so
5790** is considered bad form.
drhbee80652010-02-25 21:27:58 +00005791**
5792** The zFormat string must not be NULL.
drh7c0c4602010-03-03 22:25:18 +00005793**
5794** To avoid deadlocks and other threading problems, the sqlite3_log() routine
5795** will not use dynamically allocated memory. The log message is stored in
5796** a fixed-length buffer on the stack. If the log message is longer than
5797** a few hundred characters, it will be truncated to the length of the
5798** buffer.
drh3f280702010-02-18 18:45:09 +00005799*/
drha7564662010-02-22 19:32:31 +00005800void sqlite3_log(int iErrCode, const char *zFormat, ...);
drh3f280702010-02-18 18:45:09 +00005801
5802/*
drh833bf962010-04-28 14:42:19 +00005803** CAPI3REF: Write-Ahead Log Commit Hook
dan8d22a172010-04-19 18:03:51 +00005804**
drh005e19c2010-05-07 13:57:11 +00005805** ^The [sqlite3_wal_hook()] function is used to register a callback that
dan8d22a172010-04-19 18:03:51 +00005806** will be invoked each time a database connection commits data to a
drh005e19c2010-05-07 13:57:11 +00005807** [write-ahead log] (i.e. whenever a transaction is committed in
5808** [journal_mode | journal_mode=WAL mode]).
dan8d22a172010-04-19 18:03:51 +00005809**
drh005e19c2010-05-07 13:57:11 +00005810** ^The callback is invoked by SQLite after the commit has taken place and
dan8d22a172010-04-19 18:03:51 +00005811** the associated write-lock on the database released, so the implementation
drh005e19c2010-05-07 13:57:11 +00005812** may read, write or [checkpoint] the database as required.
dan8d22a172010-04-19 18:03:51 +00005813**
drh005e19c2010-05-07 13:57:11 +00005814** ^The first parameter passed to the callback function when it is invoked
drh833bf962010-04-28 14:42:19 +00005815** is a copy of the third parameter passed to sqlite3_wal_hook() when
drh005e19c2010-05-07 13:57:11 +00005816** registering the callback. ^The second is a copy of the database handle.
5817** ^The third parameter is the name of the database that was written to -
drhcc3af512010-06-15 12:09:06 +00005818** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
drh005e19c2010-05-07 13:57:11 +00005819** is the number of pages currently in the write-ahead log file,
5820** including those that were just committed.
dan8d22a172010-04-19 18:03:51 +00005821**
drhcc3af512010-06-15 12:09:06 +00005822** The callback function should normally return [SQLITE_OK]. ^If an error
drh5def0842010-05-05 20:00:25 +00005823** code is returned, that error will propagate back up through the
5824** SQLite code base to cause the statement that provoked the callback
dan982d4c02010-05-15 10:24:46 +00005825** to report an error, though the commit will have still occurred. If the
drhcc3af512010-06-15 12:09:06 +00005826** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
dan982d4c02010-05-15 10:24:46 +00005827** that does not correspond to any valid SQLite error code, the results
5828** are undefined.
dan8d22a172010-04-19 18:03:51 +00005829**
drh005e19c2010-05-07 13:57:11 +00005830** A single database handle may have at most a single write-ahead log callback
5831** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
drhcc3af512010-06-15 12:09:06 +00005832** previously registered write-ahead log callback. ^Note that the
drh005e19c2010-05-07 13:57:11 +00005833** [sqlite3_wal_autocheckpoint()] interface and the
5834** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
5835** those overwrite any prior [sqlite3_wal_hook()] settings.
dan8d22a172010-04-19 18:03:51 +00005836*/
drh833bf962010-04-28 14:42:19 +00005837void *sqlite3_wal_hook(
dan8d22a172010-04-19 18:03:51 +00005838 sqlite3*,
5839 int(*)(void *,sqlite3*,const char*,int),
5840 void*
5841);
5842
5843/*
dan586b9c82010-05-03 08:04:49 +00005844** CAPI3REF: Configure an auto-checkpoint
drh324e46d2010-05-03 18:51:41 +00005845**
drh005e19c2010-05-07 13:57:11 +00005846** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
drh324e46d2010-05-03 18:51:41 +00005847** [sqlite3_wal_hook()] that causes any database on [database connection] D
drh005e19c2010-05-07 13:57:11 +00005848** to automatically [checkpoint]
drh324e46d2010-05-03 18:51:41 +00005849** after committing a transaction if there are N or
drh005e19c2010-05-07 13:57:11 +00005850** more frames in the [write-ahead log] file. ^Passing zero or
drh324e46d2010-05-03 18:51:41 +00005851** a negative value as the nFrame parameter disables automatic
5852** checkpoints entirely.
5853**
drh005e19c2010-05-07 13:57:11 +00005854** ^The callback registered by this function replaces any existing callback
5855** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
drh324e46d2010-05-03 18:51:41 +00005856** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
5857** configured by this function.
drh005e19c2010-05-07 13:57:11 +00005858**
5859** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
5860** from SQL.
5861**
5862** ^Every new [database connection] defaults to having the auto-checkpoint
5863** enabled with a threshold of 1000 pages. The use of this interface
5864** is only necessary if the default setting is found to be suboptimal
5865** for a particular application.
dan586b9c82010-05-03 08:04:49 +00005866*/
5867int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
5868
5869/*
5870** CAPI3REF: Checkpoint a database
drh324e46d2010-05-03 18:51:41 +00005871**
drh005e19c2010-05-07 13:57:11 +00005872** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
5873** on [database connection] D to be [checkpointed]. ^If X is NULL or an
drh324e46d2010-05-03 18:51:41 +00005874** empty string, then a checkpoint is run on all databases of
drh6a2607a2010-05-07 18:23:24 +00005875** connection D. ^If the database connection D is not in
drh005e19c2010-05-07 13:57:11 +00005876** [WAL | write-ahead log mode] then this interface is a harmless no-op.
5877**
drh6a2607a2010-05-07 18:23:24 +00005878** ^The [wal_checkpoint pragma] can be used to invoke this interface
5879** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the
drh005e19c2010-05-07 13:57:11 +00005880** [wal_autocheckpoint pragma] can be used to cause this interface to be
5881** run whenever the WAL reaches a certain size threshold.
dan586b9c82010-05-03 08:04:49 +00005882*/
5883int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
5884
5885/*
drhb37df7b2005-10-13 02:09:49 +00005886** Undo the hack that converts floating point types to integer for
5887** builds on processors without floating point support.
5888*/
5889#ifdef SQLITE_OMIT_FLOATING_POINT
5890# undef double
5891#endif
5892
drh382c0242001-10-06 16:33:02 +00005893#ifdef __cplusplus
5894} /* End of the 'extern "C"' block */
5895#endif
danielk19774adee202004-05-08 08:23:19 +00005896#endif