3553 lines
153 KiB
C
Executable File
3553 lines
153 KiB
C
Executable File
/*
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** 2001 September 15
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**
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** The author disclaims copyright to this source code. In place of
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** a legal notice, here is a blessing:
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**
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** May you do good and not evil.
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** May you find forgiveness for yourself and forgive others.
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** May you share freely, never taking more than you give.
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**
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*************************************************************************
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** This header file defines the interface that the SQLite library
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** presents to client programs. If a C-function, structure, datatype,
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** or constant definition does not appear in this file, then it is
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** not a published API of SQLite, is subject to change without
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** notice, and should not be referenced by programs that use SQLite.
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**
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** Some of the definitions that are in this file are marked as
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** "experimental". Experimental interfaces are normally new
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** features recently added to SQLite. We do not anticipate changes
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** to experimental interfaces but reserve to make minor changes if
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** experience from use "in the wild" suggest such changes are prudent.
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**
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** The official C-language API documentation for SQLite is derived
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** from comments in this file. This file is the authoritative source
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** on how SQLite interfaces are suppose to operate.
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**
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** The name of this file under configuration management is "sqlite.h.in".
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** The makefile makes some minor changes to this file (such as inserting
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** the version number) and changes its name to "sqlite3.h" as
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** part of the build process.
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**
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** @(#) $Id: sqlite.h.in,v 1.266 2007/10/03 20:15:28 drh Exp $
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*/
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#ifndef _SQLITE3_H_
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#define _SQLITE3_H_
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#include <stdarg.h> /* Needed for the definition of va_list */
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/*
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** Make sure we can call this stuff from C++.
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*/
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#ifdef __cplusplus
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extern "C" {
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#endif
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/*
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** Add the ability to override 'extern'
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*/
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#ifndef SQLITE_EXTERN
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# define SQLITE_EXTERN extern
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#endif
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/*
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** Make sure these symbols where not defined by some previous header
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** file.
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*/
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#ifdef SQLITE_VERSION
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# undef SQLITE_VERSION
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#endif
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#ifdef SQLITE_VERSION_NUMBER
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# undef SQLITE_VERSION_NUMBER
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#endif
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/*
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** CAPI3REF: Compile-Time Library Version Numbers
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**
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** The version of the SQLite library is contained in the sqlite3.h
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** header file in a #define named SQLITE_VERSION. The SQLITE_VERSION
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** macro resolves to a string constant.
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**
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** The format of the version string is "X.Y.Z", where
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** X is the major version number, Y is the minor version number and Z
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** is the release number. The X.Y.Z might be followed by "alpha" or "beta".
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** For example "3.1.1beta".
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**
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** The X value is always 3 in SQLite. The X value only changes when
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** backwards compatibility is broken and we intend to never break
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** backwards compatibility. The Y value only changes when
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** there are major feature enhancements that are forwards compatible
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** but not backwards compatible. The Z value is incremented with
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** each release but resets back to 0 when Y is incremented.
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**
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** The SQLITE_VERSION_NUMBER is an integer with the value
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** (X*1000000 + Y*1000 + Z). For example, for version "3.1.1beta",
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** SQLITE_VERSION_NUMBER is set to 3001001. To detect if they are using
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** version 3.1.1 or greater at compile time, programs may use the test
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** (SQLITE_VERSION_NUMBER>=3001001).
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**
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** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()].
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*/
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#define SQLITE_VERSION "3.5.1"
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#define SQLITE_VERSION_NUMBER 3005001
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/*
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** CAPI3REF: Run-Time Library Version Numbers
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**
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** These routines return values equivalent to the header constants
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** [SQLITE_VERSION] and [SQLITE_VERSION_NUMBER]. The values returned
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** by this routines should only be different from the header values
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** if you compile your program using an sqlite3.h header from a
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** different version of SQLite that the version of the library you
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** link against.
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**
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** The sqlite3_version[] string constant contains the text of the
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** [SQLITE_VERSION] string. The sqlite3_libversion() function returns
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** a poiner to the sqlite3_version[] string constant. The function
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** is provided for DLL users who can only access functions and not
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** constants within the DLL.
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*/
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SQLITE_EXTERN const char sqlite3_version[];
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const char *sqlite3_libversion(void);
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int sqlite3_libversion_number(void);
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/*
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** CAPI3REF: Test To See If The Library Is Threadsafe
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**
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** This routine returns TRUE (nonzero) if SQLite was compiled with
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** all of its mutexes enabled and is thus threadsafe. It returns
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** zero if the particular build is for single-threaded operation
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** only.
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**
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** Really all this routine does is return true if SQLite was compiled
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** with the -DSQLITE_THREADSAFE=1 option and false if
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** compiled with -DSQLITE_THREADSAFE=0. If SQLite uses an
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** application-defined mutex subsystem, malloc subsystem, collating
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** sequence, VFS, SQL function, progress callback, commit hook,
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** extension, or other accessories and these add-ons are not
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** threadsafe, then clearly the combination will not be threadsafe
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** either. Hence, this routine never reports that the library
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** is guaranteed to be threadsafe, only when it is guaranteed not
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** to be.
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**
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** This is an experimental API and may go away or change in future
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** releases.
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*/
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int sqlite3_threadsafe(void);
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/*
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** CAPI3REF: Database Connection Handle
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**
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** Each open SQLite database is represented by pointer to an instance of the
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** opaque structure named "sqlite3". It is useful to think of an sqlite3
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** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
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** [sqlite3_open_v2()] interfaces are its constructors
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** and [sqlite3_close()] is its destructor. There are many other interfaces
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** (such as [sqlite3_prepare_v2()], [sqlite3_create_function()], and
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** [sqlite3_busy_timeout()] to name but three) that are methods on this
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** object.
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*/
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typedef struct sqlite3 sqlite3;
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/*
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** CAPI3REF: 64-Bit Integer Types
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**
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** Some compilers do not support the "long long" datatype. So we have
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** to do compiler-specific typedefs for 64-bit signed and unsigned integers.
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**
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** Many SQLite interface functions require a 64-bit integer arguments.
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** Those interfaces are declared using this typedef.
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*/
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#ifdef SQLITE_INT64_TYPE
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typedef SQLITE_INT64_TYPE sqlite_int64;
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typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
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#elif defined(_MSC_VER) || defined(__BORLANDC__)
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typedef __int64 sqlite_int64;
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typedef unsigned __int64 sqlite_uint64;
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#else
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typedef long long int sqlite_int64;
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typedef unsigned long long int sqlite_uint64;
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#endif
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typedef sqlite_int64 sqlite3_int64;
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typedef sqlite_uint64 sqlite3_uint64;
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/*
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** If compiling for a processor that lacks floating point support,
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** substitute integer for floating-point
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*/
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#ifdef SQLITE_OMIT_FLOATING_POINT
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# define double sqlite3_int64
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#endif
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/*
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** CAPI3REF: Closing A Database Connection
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**
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** Call this function with a pointer to a structure that was previously
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** returned from [sqlite3_open()], [sqlite3_open16()], or
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** [sqlite3_open_v2()] and the corresponding database will by
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** closed.
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**
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** All SQL statements prepared using [sqlite3_prepare_v2()] or
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** [sqlite3_prepare16_v2()] must be destroyed using [sqlite3_finalize()]
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** before this routine is called. Otherwise, SQLITE_BUSY is returned and the
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** database connection remains open.
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**
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** Passing this routine a database connection that has already been
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** closed results in undefined behavior. If other interfaces that
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** reference the same database connection are pending (either in the
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** same thread or in different threads) when this routine is called,
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** then the behavior is undefined and is almost certainly undesirable.
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*/
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int sqlite3_close(sqlite3 *);
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/*
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** The type for a callback function.
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** This is legacy and deprecated. It is included for historical
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** compatibility and is not documented.
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*/
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typedef int (*sqlite3_callback)(void*,int,char**, char**);
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/*
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** CAPI3REF: One-Step Query Execution Interface
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**
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** This interface is used to do a one-time evaluatation of zero
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** or more SQL statements. UTF-8 text of the SQL statements to
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** be evaluted is passed in as the second parameter. The statements
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** are prepared one by one using [sqlite3_prepare()], evaluated
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** using [sqlite3_step()], then destroyed using [sqlite3_finalize()].
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**
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** If one or more of the SQL statements are queries, then
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** the callback function specified by the 3rd parameter is
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** invoked once for each row of the query result. This callback
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** should normally return 0. If the callback returns a non-zero
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** value then the query is aborted, all subsequent SQL statements
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** are skipped and the sqlite3_exec() function returns the [SQLITE_ABORT].
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**
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** The 4th parameter to this interface is an arbitrary pointer that is
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** passed through to the callback function as its first parameter.
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**
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** The 2nd parameter to the callback function is the number of
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** columns in the query result. The 3rd parameter to the callback
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** is an array of strings holding the values for each column
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** as extracted using [sqlite3_column_text()].
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** The 4th parameter to the callback is an array of strings
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** obtained using [sqlite3_column_name()] and holding
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** the names of each column.
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**
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** The callback function may be NULL, even for queries. A NULL
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** callback is not an error. It just means that no callback
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** will be invoked.
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**
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** If an error occurs while parsing or evaluating the SQL (but
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** not while executing the callback) then an appropriate error
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** message is written into memory obtained from [sqlite3_malloc()] and
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** *errmsg is made to point to that message. The calling function
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** is responsible for freeing the memory using [sqlite3_free()].
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** If errmsg==NULL, then no error message is ever written.
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**
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** The return value is is SQLITE_OK if there are no errors and
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** some other [SQLITE_OK | return code] if there is an error.
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** The particular return value depends on the type of error.
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**
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*/
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int sqlite3_exec(
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sqlite3*, /* An open database */
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const char *sql, /* SQL to be evaluted */
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int (*callback)(void*,int,char**,char**), /* Callback function */
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void *, /* 1st argument to callback */
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char **errmsg /* Error msg written here */
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);
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/*
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** CAPI3REF: Result Codes
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** KEYWORDS: SQLITE_OK
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**
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** Many SQLite functions return an integer result code from the set shown
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** above in order to indicates success or failure.
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**
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** The result codes above are the only ones returned by SQLite in its
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** default configuration. However, the [sqlite3_extended_result_codes()]
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** API can be used to set a database connectoin to return more detailed
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** result codes.
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**
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** See also: [SQLITE_IOERR_READ | extended result codes]
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**
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*/
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#define SQLITE_OK 0 /* Successful result */
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/* beginning-of-error-codes */
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#define SQLITE_ERROR 1 /* SQL error or missing database */
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#define SQLITE_INTERNAL 2 /* NOT USED. Internal logic error in SQLite */
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#define SQLITE_PERM 3 /* Access permission denied */
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#define SQLITE_ABORT 4 /* Callback routine requested an abort */
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#define SQLITE_BUSY 5 /* The database file is locked */
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#define SQLITE_LOCKED 6 /* A table in the database is locked */
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#define SQLITE_NOMEM 7 /* A malloc() failed */
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#define SQLITE_READONLY 8 /* Attempt to write a readonly database */
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#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
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#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
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#define SQLITE_CORRUPT 11 /* The database disk image is malformed */
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#define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */
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#define SQLITE_FULL 13 /* Insertion failed because database is full */
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#define SQLITE_CANTOPEN 14 /* Unable to open the database file */
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#define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */
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#define SQLITE_EMPTY 16 /* Database is empty */
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#define SQLITE_SCHEMA 17 /* The database schema changed */
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#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
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#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
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#define SQLITE_MISMATCH 20 /* Data type mismatch */
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#define SQLITE_MISUSE 21 /* Library used incorrectly */
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#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
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#define SQLITE_AUTH 23 /* Authorization denied */
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#define SQLITE_FORMAT 24 /* Auxiliary database format error */
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#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
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#define SQLITE_NOTADB 26 /* File opened that is not a database file */
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#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
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#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
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/* end-of-error-codes */
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/*
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** CAPI3REF: Extended Result Codes
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**
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** In its default configuration, SQLite API routines return one of 26 integer
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** result codes described at result-codes. However, experience has shown that
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** many of these result codes are too course-grained. They do not provide as
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** much information about problems as users might like. In an effort to
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** address this, newer versions of SQLite (version 3.3.8 and later) include
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** support for additional result codes that provide more detailed information
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** about errors. The extended result codes are enabled (or disabled) for
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** each database
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** connection using the [sqlite3_extended_result_codes()] API.
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**
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** Some of the available extended result codes are listed above.
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** We expect the number of extended result codes will be expand
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** over time. Software that uses extended result codes should expect
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** to see new result codes in future releases of SQLite.
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**
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** The symbolic name for an extended result code always contains a related
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** primary result code as a prefix. Primary result codes contain a single
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** "_" character. Extended result codes contain two or more "_" characters.
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** The numeric value of an extended result code can be converted to its
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** corresponding primary result code by masking off the lower 8 bytes.
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**
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** The SQLITE_OK result code will never be extended. It will always
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** be exactly zero.
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*/
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#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
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#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
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#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
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#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
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#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
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#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
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#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
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#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
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#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
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#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
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#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
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#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
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/*
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** CAPI3REF: Flags For File Open Operations
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**
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** Combination of the following bit values are used as the
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** third argument to the [sqlite3_open_v2()] interface and
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** as fourth argument to the xOpen method of the
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** [sqlite3_vfs] object.
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**
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*/
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#define SQLITE_OPEN_READONLY 0x00000001
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#define SQLITE_OPEN_READWRITE 0x00000002
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#define SQLITE_OPEN_CREATE 0x00000004
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#define SQLITE_OPEN_DELETEONCLOSE 0x00000008
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#define SQLITE_OPEN_EXCLUSIVE 0x00000010
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#define SQLITE_OPEN_MAIN_DB 0x00000100
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#define SQLITE_OPEN_TEMP_DB 0x00000200
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#define SQLITE_OPEN_TRANSIENT_DB 0x00000400
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#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800
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#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000
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#define SQLITE_OPEN_SUBJOURNAL 0x00002000
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#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000
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/*
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** CAPI3REF: Device Characteristics
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**
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** The xDeviceCapabilities method of the [sqlite3_io_methods]
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** object returns an integer which is a vector of the following
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** bit values expressing I/O characteristics of the mass storage
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** device that holds the file that the [sqlite3_io_methods]
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** refers to.
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**
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** The SQLITE_IOCAP_ATOMIC property means that all writes of
|
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** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
|
|
** mean that writes of blocks that are nnn bytes in size and
|
|
** are aligned to an address which is an integer multiple of
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** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
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** that when data is appended to a file, the data is appended
|
|
** first then the size of the file is extended, never the other
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** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
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** information is written to disk in the same order as calls
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** to xWrite().
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*/
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#define SQLITE_IOCAP_ATOMIC 0x00000001
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#define SQLITE_IOCAP_ATOMIC512 0x00000002
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#define SQLITE_IOCAP_ATOMIC1K 0x00000004
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#define SQLITE_IOCAP_ATOMIC2K 0x00000008
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#define SQLITE_IOCAP_ATOMIC4K 0x00000010
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#define SQLITE_IOCAP_ATOMIC8K 0x00000020
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#define SQLITE_IOCAP_ATOMIC16K 0x00000040
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#define SQLITE_IOCAP_ATOMIC32K 0x00000080
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#define SQLITE_IOCAP_ATOMIC64K 0x00000100
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#define SQLITE_IOCAP_SAFE_APPEND 0x00000200
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#define SQLITE_IOCAP_SEQUENTIAL 0x00000400
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/*
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** CAPI3REF: File Locking Levels
|
|
**
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** SQLite uses one of the following integer values as the second
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** argument to calls it makes to the xLock() and xUnlock() methods
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** of an [sqlite3_io_methods] object.
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*/
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#define SQLITE_LOCK_NONE 0
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#define SQLITE_LOCK_SHARED 1
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#define SQLITE_LOCK_RESERVED 2
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#define SQLITE_LOCK_PENDING 3
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#define SQLITE_LOCK_EXCLUSIVE 4
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/*
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** CAPI3REF: Synchronization Type Flags
|
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**
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** When SQLite invokes the xSync() method of an [sqlite3_io_methods]
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** object it uses a combination of the following integer values as
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** the second argument.
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**
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** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
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** sync operation only needs to flush data to mass storage. Inode
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** information need not be flushed. The SQLITE_SYNC_NORMAL means
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** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means
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** to use Mac OS-X style fullsync instead of fsync().
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*/
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#define SQLITE_SYNC_NORMAL 0x00002
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#define SQLITE_SYNC_FULL 0x00003
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#define SQLITE_SYNC_DATAONLY 0x00010
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/*
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** CAPI3REF: OS Interface Open File Handle
|
|
**
|
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** An [sqlite3_file] object represents an open file in the OS
|
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** interface layer. Individual OS interface implementations will
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** want to subclass this object by appending additional fields
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** for their own use. The pMethods entry is a pointer to an
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** [sqlite3_io_methods] object that defines methods for performing
|
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** I/O operations on the open file.
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*/
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typedef struct sqlite3_file sqlite3_file;
|
|
struct sqlite3_file {
|
|
const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
|
|
};
|
|
|
|
/*
|
|
** CAPI3REF: OS Interface File Virtual Methods Object
|
|
**
|
|
** Every file opened by the [sqlite3_vfs] xOpen method contains a pointer to
|
|
** an instance of the this object. This object defines the
|
|
** methods used to perform various operations against the open file.
|
|
**
|
|
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
|
|
** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
|
|
* The second choice is an
|
|
** OS-X style fullsync. The SQLITE_SYNC_DATA flag may be ORed in to
|
|
** indicate that only the data of the file and not its inode needs to be
|
|
** synced.
|
|
**
|
|
** The integer values to xLock() and xUnlock() are one of
|
|
** <ul>
|
|
** <li> [SQLITE_LOCK_NONE],
|
|
** <li> [SQLITE_LOCK_SHARED],
|
|
** <li> [SQLITE_LOCK_RESERVED],
|
|
** <li> [SQLITE_LOCK_PENDING], or
|
|
** <li> [SQLITE_LOCK_EXCLUSIVE].
|
|
** </ul>
|
|
** xLock() increases the lock. xUnlock() decreases the lock.
|
|
** The xCheckReservedLock() method looks
|
|
** to see if any database connection, either in this
|
|
** process or in some other process, is holding an RESERVED,
|
|
** PENDING, or EXCLUSIVE lock on the file. It returns true
|
|
** if such a lock exists and false if not.
|
|
**
|
|
** The xFileControl() method is a generic interface that allows custom
|
|
** VFS implementations to directly control an open file using the
|
|
** [sqlite3_file_control()] interface. The second "op" argument
|
|
** is an integer opcode. The third
|
|
** argument is a generic pointer which is intended to be a pointer
|
|
** to a structure that may contain arguments or space in which to
|
|
** write return values. Potential uses for xFileControl() might be
|
|
** functions to enable blocking locks with timeouts, to change the
|
|
** locking strategy (for example to use dot-file locks), to inquire
|
|
** about the status of a lock, or to break stale locks. The SQLite
|
|
** core reserves opcodes less than 100 for its own use.
|
|
** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
|
|
** Applications that define a custom xFileControl method should use opcodes
|
|
** greater than 100 to avoid conflicts.
|
|
**
|
|
** The xSectorSize() method returns the sector size of the
|
|
** device that underlies the file. The sector size is the
|
|
** minimum write that can be performed without disturbing
|
|
** other bytes in the file. The xDeviceCharacteristics()
|
|
** method returns a bit vector describing behaviors of the
|
|
** underlying device:
|
|
**
|
|
** <ul>
|
|
** <li> [SQLITE_IOCAP_ATOMIC]
|
|
** <li> [SQLITE_IOCAP_ATOMIC512]
|
|
** <li> [SQLITE_IOCAP_ATOMIC1K]
|
|
** <li> [SQLITE_IOCAP_ATOMIC2K]
|
|
** <li> [SQLITE_IOCAP_ATOMIC4K]
|
|
** <li> [SQLITE_IOCAP_ATOMIC8K]
|
|
** <li> [SQLITE_IOCAP_ATOMIC16K]
|
|
** <li> [SQLITE_IOCAP_ATOMIC32K]
|
|
** <li> [SQLITE_IOCAP_ATOMIC64K]
|
|
** <li> [SQLITE_IOCAP_SAFE_APPEND]
|
|
** <li> [SQLITE_IOCAP_SEQUENTIAL]
|
|
** </ul>
|
|
**
|
|
** The SQLITE_IOCAP_ATOMIC property means that all writes of
|
|
** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
|
|
** mean that writes of blocks that are nnn bytes in size and
|
|
** are aligned to an address which is an integer multiple of
|
|
** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
|
|
** that when data is appended to a file, the data is appended
|
|
** first then the size of the file is extended, never the other
|
|
** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
|
|
** information is written to disk in the same order as calls
|
|
** to xWrite().
|
|
*/
|
|
typedef struct sqlite3_io_methods sqlite3_io_methods;
|
|
struct sqlite3_io_methods {
|
|
int iVersion;
|
|
int (*xClose)(sqlite3_file*);
|
|
int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
|
|
int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
|
|
int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
|
|
int (*xSync)(sqlite3_file*, int flags);
|
|
int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
|
|
int (*xLock)(sqlite3_file*, int);
|
|
int (*xUnlock)(sqlite3_file*, int);
|
|
int (*xCheckReservedLock)(sqlite3_file*);
|
|
int (*xFileControl)(sqlite3_file*, int op, void *pArg);
|
|
int (*xSectorSize)(sqlite3_file*);
|
|
int (*xDeviceCharacteristics)(sqlite3_file*);
|
|
/* Additional methods may be added in future releases */
|
|
};
|
|
|
|
/*
|
|
** CAPI3REF: Standard File Control Opcodes
|
|
**
|
|
** These integer constants are opcodes for the xFileControl method
|
|
** of the [sqlite3_io_methods] object and to the [sqlite3_file_control()]
|
|
** interface.
|
|
**
|
|
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
|
|
** opcode cases the xFileControl method to write the current state of
|
|
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
|
|
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
|
|
** into an integer that the pArg argument points to. This capability
|
|
** is used during testing and only needs to be supported when SQLITE_TEST
|
|
** is defined.
|
|
*/
|
|
#define SQLITE_FCNTL_LOCKSTATE 1
|
|
|
|
/*
|
|
** CAPI3REF: Mutex Handle
|
|
**
|
|
** The mutex module within SQLite defines [sqlite3_mutex] to be an
|
|
** abstract type for a mutex object. The SQLite core never looks
|
|
** at the internal representation of an [sqlite3_mutex]. It only
|
|
** deals with pointers to the [sqlite3_mutex] object.
|
|
**
|
|
** Mutexes are created using [sqlite3_mutex_alloc()].
|
|
*/
|
|
typedef struct sqlite3_mutex sqlite3_mutex;
|
|
|
|
/*
|
|
** CAPI3REF: OS Interface Object
|
|
**
|
|
** An instance of this object defines the interface between the
|
|
** SQLite core and the underlying operating system. The "vfs"
|
|
** in the name of the object stands for "virtual file system".
|
|
**
|
|
** The iVersion field is initially 1 but may be larger for future
|
|
** versions of SQLite. Additional fields may be appended to this
|
|
** object when the iVersion value is increased.
|
|
**
|
|
** The szOsFile field is the size of the subclassed [sqlite3_file]
|
|
** structure used by this VFS. mxPathname is the maximum length of
|
|
** a pathname in this VFS.
|
|
**
|
|
** Registered vfs modules are kept on a linked list formed by
|
|
** the pNext pointer. The [sqlite3_vfs_register()]
|
|
** and [sqlite3_vfs_unregister()] interfaces manage this list
|
|
** in a thread-safe way. The [sqlite3_vfs_find()] interface
|
|
** searches the list.
|
|
**
|
|
** The pNext field is the only fields in the sqlite3_vfs
|
|
** structure that SQLite will ever modify. SQLite will only access
|
|
** or modify this field while holding a particular static mutex.
|
|
** The application should never modify anything within the sqlite3_vfs
|
|
** object once the object has been registered.
|
|
**
|
|
** The zName field holds the name of the VFS module. The name must
|
|
** be unique across all VFS modules.
|
|
**
|
|
** SQLite will guarantee that the zFilename string passed to
|
|
** xOpen() is a full pathname as generated by xFullPathname() and
|
|
** that the string will be valid and unchanged until xClose() is
|
|
** called. So the [sqlite3_file] can store a pointer to the
|
|
** filename if it needs to remember the filename for some reason.
|
|
**
|
|
** The flags argument to xOpen() is a copy of the flags argument
|
|
** to [sqlite3_open_v2()]. If [sqlite3_open()] or [sqlite3_open16()]
|
|
** is used, then flags is [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
|
|
** If xOpen() opens a file read-only then it sets *pOutFlags to
|
|
** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be
|
|
** set.
|
|
**
|
|
** SQLite will also add one of the following flags to the xOpen()
|
|
** call, depending on the object being opened:
|
|
**
|
|
** <ul>
|
|
** <li> [SQLITE_OPEN_MAIN_DB]
|
|
** <li> [SQLITE_OPEN_MAIN_JOURNAL]
|
|
** <li> [SQLITE_OPEN_TEMP_DB]
|
|
** <li> [SQLITE_OPEN_TEMP_JOURNAL]
|
|
** <li> [SQLITE_OPEN_TRANSIENT_DB]
|
|
** <li> [SQLITE_OPEN_SUBJOURNAL]
|
|
** <li> [SQLITE_OPEN_MASTER_JOURNAL]
|
|
** </ul>
|
|
**
|
|
** The file I/O implementation can use the object type flags to
|
|
** changes the way it deals with files. For example, an application
|
|
** that does not care about crash recovery or rollback, might make
|
|
** the open of a journal file a no-op. Writes to this journal are
|
|
** also a no-op. Any attempt to read the journal return SQLITE_IOERR.
|
|
** Or the implementation might recognize the a database file will
|
|
** be doing page-aligned sector reads and writes in a random order
|
|
** and set up its I/O subsystem accordingly.
|
|
**
|
|
** SQLite might also add one of the following flags to the xOpen
|
|
** method:
|
|
**
|
|
** <ul>
|
|
** <li> [SQLITE_OPEN_DELETEONCLOSE]
|
|
** <li> [SQLITE_OPEN_EXCLUSIVE]
|
|
** </ul>
|
|
**
|
|
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
|
|
** deleted when it is closed. This will always be set for TEMP
|
|
** databases and journals and for subjournals. The
|
|
** [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened
|
|
** for exclusive access. This flag is set for all files except
|
|
** for the main database file.
|
|
**
|
|
** Space to hold the [sqlite3_file] structure passed as the third
|
|
** argument to xOpen is allocated by caller (the SQLite core).
|
|
** szOsFile bytes are allocated for this object. The xOpen method
|
|
** fills in the allocated space.
|
|
**
|
|
** The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
|
|
** to test for the existance of a file,
|
|
** or [SQLITE_ACCESS_READWRITE] to test to see
|
|
** if a file is readable and writable, or [SQLITE_ACCESS_READ]
|
|
** to test to see if a file is at least readable. The file can be a
|
|
** directory.
|
|
**
|
|
** SQLite will always allocate at least mxPathname+1 byte for
|
|
** the output buffers for xGetTempname and xFullPathname. The exact
|
|
** size of the output buffer is also passed as a parameter to both
|
|
** methods. If the output buffer is not large enough, SQLITE_CANTOPEN
|
|
** should be returned. As this is handled as a fatal error by SQLite,
|
|
** vfs implementations should endevour to prevent this by setting
|
|
** mxPathname to a sufficiently large value.
|
|
**
|
|
** The xRandomness(), xSleep(), and xCurrentTime() interfaces
|
|
** are not strictly a part of the filesystem, but they are
|
|
** included in the VFS structure for completeness.
|
|
** The xRandomness() function attempts to return nBytes bytes
|
|
** of good-quality randomness into zOut. The return value is
|
|
** the actual number of bytes of randomness obtained. The
|
|
** xSleep() method cause the calling thread to sleep for at
|
|
** least the number of microseconds given. The xCurrentTime()
|
|
** method returns a Julian Day Number for the current date and
|
|
** time.
|
|
*/
|
|
typedef struct sqlite3_vfs sqlite3_vfs;
|
|
struct sqlite3_vfs {
|
|
int iVersion; /* Structure version number */
|
|
int szOsFile; /* Size of subclassed sqlite3_file */
|
|
int mxPathname; /* Maximum file pathname length */
|
|
sqlite3_vfs *pNext; /* Next registered VFS */
|
|
const char *zName; /* Name of this virtual file system */
|
|
void *pAppData; /* Pointer to application-specific data */
|
|
int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
|
|
int flags, int *pOutFlags);
|
|
int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
|
|
int (*xAccess)(sqlite3_vfs*, const char *zName, int flags);
|
|
int (*xGetTempname)(sqlite3_vfs*, int nOut, char *zOut);
|
|
int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
|
|
void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
|
|
void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
|
|
void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
|
|
void (*xDlClose)(sqlite3_vfs*, void*);
|
|
int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
|
|
int (*xSleep)(sqlite3_vfs*, int microseconds);
|
|
int (*xCurrentTime)(sqlite3_vfs*, double*);
|
|
/* New fields may be appended in figure versions. The iVersion
|
|
** value will increment whenever this happens. */
|
|
};
|
|
|
|
/*
|
|
** CAPI3REF: Flags for the xAccess VFS method
|
|
**
|
|
** These integer constants can be used as the third parameter to
|
|
** the xAccess method of an [sqlite3_vfs] object. They determine
|
|
** the kind of what kind of permissions the xAccess method is
|
|
** looking for. With SQLITE_ACCESS_EXISTS, the xAccess method
|
|
** simply checks to see if the file exists. With SQLITE_ACCESS_READWRITE,
|
|
** the xAccess method checks to see if the file is both readable
|
|
** and writable. With SQLITE_ACCESS_READ the xAccess method
|
|
** checks to see if the file is readable.
|
|
*/
|
|
#define SQLITE_ACCESS_EXISTS 0
|
|
#define SQLITE_ACCESS_READWRITE 1
|
|
#define SQLITE_ACCESS_READ 2
|
|
|
|
/*
|
|
** CAPI3REF: Enable Or Disable Extended Result Codes
|
|
**
|
|
** This routine enables or disables the
|
|
** [SQLITE_IOERR_READ | extended result codes] feature.
|
|
** By default, SQLite API routines return one of only 26 integer
|
|
** [SQLITE_OK | result codes]. When extended result codes
|
|
** are enabled by this routine, the repetoire of result codes can be
|
|
** much larger and can (hopefully) provide more detailed information
|
|
** about the cause of an error.
|
|
**
|
|
** The second argument is a boolean value that turns extended result
|
|
** codes on and off. Extended result codes are off by default for
|
|
** backwards compatibility with older versions of SQLite.
|
|
*/
|
|
int sqlite3_extended_result_codes(sqlite3*, int onoff);
|
|
|
|
/*
|
|
** CAPI3REF: Last Insert Rowid
|
|
**
|
|
** Each entry in an SQLite table has a unique 64-bit signed integer key
|
|
** called the "rowid". The rowid is always available as an undeclared
|
|
** column named ROWID, OID, or _ROWID_. If the table has a column of
|
|
** type INTEGER PRIMARY KEY then that column is another an alias for the
|
|
** rowid.
|
|
**
|
|
** This routine returns the rowid of the most recent INSERT into
|
|
** the database from the database connection given in the first
|
|
** argument. If no inserts have ever occurred on this database
|
|
** connection, zero is returned.
|
|
**
|
|
** If an INSERT occurs within a trigger, then the rowid of the
|
|
** inserted row is returned by this routine as long as the trigger
|
|
** is running. But once the trigger terminates, the value returned
|
|
** by this routine reverts to the last value inserted before the
|
|
** trigger fired.
|
|
**
|
|
** If another thread does a new insert on the same database connection
|
|
** while this routine is running and thus changes the last insert rowid,
|
|
** then the return value of this routine is undefined.
|
|
*/
|
|
sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
|
|
|
|
/*
|
|
** CAPI3REF: Count The Number Of Rows Modified
|
|
**
|
|
** This function returns the number of database rows that were changed
|
|
** (or inserted or deleted) by the most recent SQL statement. Only
|
|
** changes that are directly specified by the INSERT, UPDATE, or
|
|
** DELETE statement are counted. Auxiliary changes caused by
|
|
** triggers are not counted. Use the [sqlite3_total_changes()] function
|
|
** to find the total number of changes including changes caused by triggers.
|
|
**
|
|
** Within the body of a trigger, the sqlite3_changes() interface can be
|
|
** called to find the number of
|
|
** changes in the most recently completed INSERT, UPDATE, or DELETE
|
|
** statement within the body of the trigger.
|
|
**
|
|
** All changes are counted, even if they were later undone by a
|
|
** ROLLBACK or ABORT. Except, changes associated with creating and
|
|
** dropping tables are not counted.
|
|
**
|
|
** If a callback invokes [sqlite3_exec()] or [sqlite3_step()] recursively,
|
|
** then the changes in the inner, recursive call are counted together
|
|
** with the changes in the outer call.
|
|
**
|
|
** SQLite implements the command "DELETE FROM table" without a WHERE clause
|
|
** by dropping and recreating the table. (This is much faster than going
|
|
** through and deleting individual elements from the table.) Because of
|
|
** this optimization, the change count for "DELETE FROM table" will be
|
|
** zero regardless of the number of elements that were originally in the
|
|
** table. To get an accurate count of the number of rows deleted, use
|
|
** "DELETE FROM table WHERE 1" instead.
|
|
**
|
|
** If another thread makes changes on the same database connection
|
|
** while this routine is running then the return value of this routine
|
|
** is undefined.
|
|
*/
|
|
int sqlite3_changes(sqlite3*);
|
|
|
|
/*
|
|
** CAPI3REF: Total Number Of Rows Modified
|
|
***
|
|
** This function returns the number of database rows that have been
|
|
** modified by INSERT, UPDATE or DELETE statements since the database handle
|
|
** was opened. This includes UPDATE, INSERT and DELETE statements executed
|
|
** as part of trigger programs. All changes are counted as soon as the
|
|
** statement that makes them is completed (when the statement handle is
|
|
** passed to [sqlite3_reset()] or [sqlite3_finalize()]).
|
|
**
|
|
** See also the [sqlite3_change()] interface.
|
|
**
|
|
** SQLite implements the command "DELETE FROM table" without a WHERE clause
|
|
** by dropping and recreating the table. (This is much faster than going
|
|
** through and deleting individual elements form the table.) Because of
|
|
** this optimization, the change count for "DELETE FROM table" will be
|
|
** zero regardless of the number of elements that were originally in the
|
|
** table. To get an accurate count of the number of rows deleted, use
|
|
** "DELETE FROM table WHERE 1" instead.
|
|
**
|
|
** If another thread makes changes on the same database connection
|
|
** while this routine is running then the return value of this routine
|
|
** is undefined.
|
|
*/
|
|
int sqlite3_total_changes(sqlite3*);
|
|
|
|
/*
|
|
** CAPI3REF: Interrupt A Long-Running Query
|
|
**
|
|
** This function causes any pending database operation to abort and
|
|
** return at its earliest opportunity. This routine is typically
|
|
** called in response to a user action such as pressing "Cancel"
|
|
** or Ctrl-C where the user wants a long query operation to halt
|
|
** immediately.
|
|
**
|
|
** It is safe to call this routine from a thread different from the
|
|
** thread that is currently running the database operation. But it
|
|
** is not safe to call this routine with a database connection that
|
|
** is closed or might close before sqlite3_interrupt() returns.
|
|
**
|
|
** The SQL operation that is interrupted will return [SQLITE_INTERRUPT].
|
|
** If an interrupted operation was an update that is inside an
|
|
** explicit transaction, then the entire transaction will be rolled
|
|
** back automatically.
|
|
*/
|
|
void sqlite3_interrupt(sqlite3*);
|
|
|
|
/*
|
|
** CAPI3REF: Determine If An SQL Statement Is Complete
|
|
**
|
|
** These functions return true if the given input string comprises
|
|
** one or more complete SQL statements. For the sqlite3_complete() call,
|
|
** the parameter must be a nul-terminated UTF-8 string. For
|
|
** sqlite3_complete16(), a nul-terminated machine byte order UTF-16 string
|
|
** is required.
|
|
**
|
|
** These routines are useful for command-line input to determine if the
|
|
** currently entered text forms one or more complete SQL statements or
|
|
** if additional input is needed before sending the statements into
|
|
** SQLite for parsing. The algorithm is simple. If the
|
|
** last token other than spaces and comments is a semicolon, then return
|
|
** true. Actually, the algorithm is a little more complicated than that
|
|
** in order to deal with triggers, but the basic idea is the same: the
|
|
** statement is not complete unless it ends in a semicolon.
|
|
*/
|
|
int sqlite3_complete(const char *sql);
|
|
int sqlite3_complete16(const void *sql);
|
|
|
|
/*
|
|
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
|
|
**
|
|
** This routine identifies a callback function that might be invoked
|
|
** whenever an attempt is made to open a database table
|
|
** that another thread or process has locked.
|
|
** If the busy callback is NULL, then [SQLITE_BUSY]
|
|
** (or sometimes [SQLITE_IOERR_BLOCKED])
|
|
** is returned immediately upon encountering the lock.
|
|
** If the busy callback is not NULL, then the
|
|
** callback will be invoked with two arguments. The
|
|
** first argument to the handler is a copy of the void* pointer which
|
|
** is the third argument to this routine. The second argument to
|
|
** the handler is the number of times that the busy handler has
|
|
** been invoked for this locking event. If the
|
|
** busy callback returns 0, then no additional attempts are made to
|
|
** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
|
|
** If the callback returns non-zero, then another attempt is made to open the
|
|
** database for reading and the cycle repeats.
|
|
**
|
|
** The presence of a busy handler does not guarantee that
|
|
** it will be invoked when there is lock contention.
|
|
** If SQLite determines that invoking the busy handler could result in
|
|
** a deadlock, it will return [SQLITE_BUSY] instead.
|
|
** Consider a scenario where one process is holding a read lock that
|
|
** it is trying to promote to a reserved lock and
|
|
** a second process is holding a reserved lock that it is trying
|
|
** to promote to an exclusive lock. The first process cannot proceed
|
|
** because it is blocked by the second and the second process cannot
|
|
** proceed because it is blocked by the first. If both processes
|
|
** invoke the busy handlers, neither will make any progress. Therefore,
|
|
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
|
|
** will induce the first process to release its read lock and allow
|
|
** the second process to proceed.
|
|
**
|
|
** The default busy callback is NULL.
|
|
**
|
|
** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED] when
|
|
** SQLite is in the middle of a large transaction where all the
|
|
** changes will not fit into the in-memory cache. SQLite will
|
|
** already hold a RESERVED lock on the database file, but it needs
|
|
** to promote this lock to EXCLUSIVE so that it can spill cache
|
|
** pages into the database file without harm to concurrent
|
|
** readers. If it is unable to promote the lock, then the in-memory
|
|
** cache will be left in an inconsistent state and so the error
|
|
** code is promoted from the relatively benign [SQLITE_BUSY] to
|
|
** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion
|
|
** forces an automatic rollback of the changes. See the
|
|
** <a href="http://www.sqlite.org/cvstrac/wiki?p=CorruptionFollowingBusyError">
|
|
** CorruptionFollowingBusyError</a> wiki page for a discussion of why
|
|
** this is important.
|
|
**
|
|
** Sqlite is re-entrant, so the busy handler may start a new query.
|
|
** (It is not clear why anyone would every want to do this, but it
|
|
** is allowed, in theory.) But the busy handler may not close the
|
|
** database. Closing the database from a busy handler will delete
|
|
** data structures out from under the executing query and will
|
|
** probably result in a segmentation fault or other runtime error.
|
|
**
|
|
** There can only be a single busy handler defined for each database
|
|
** connection. Setting a new busy handler clears any previous one.
|
|
** Note that calling [sqlite3_busy_timeout()] will also set or clear
|
|
** the busy handler.
|
|
**
|
|
** When operating in [sqlite3_enable_shared_cache | shared cache mode],
|
|
** only a single busy handler can be defined for each database file.
|
|
** So if two database connections share a single cache, then changing
|
|
** the busy handler on one connection will also change the busy
|
|
** handler in the other connection. The busy handler is invoked
|
|
** in the thread that was running when the SQLITE_BUSY was hit.
|
|
*/
|
|
int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
|
|
|
|
/*
|
|
** CAPI3REF: Set A Busy Timeout
|
|
**
|
|
** This routine sets a busy handler that sleeps for a while when a
|
|
** table is locked. The handler will sleep multiple times until
|
|
** at least "ms" milliseconds of sleeping have been done. After
|
|
** "ms" milliseconds of sleeping, the handler returns 0 which
|
|
** causes [sqlite3_step()] to return [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
|
|
**
|
|
** Calling this routine with an argument less than or equal to zero
|
|
** turns off all busy handlers.
|
|
**
|
|
** There can only be a single busy handler for a particular database
|
|
** connection. If another busy handler was defined
|
|
** (using [sqlite3_busy_handler()]) prior to calling
|
|
** this routine, that other busy handler is cleared.
|
|
*/
|
|
int sqlite3_busy_timeout(sqlite3*, int ms);
|
|
|
|
/*
|
|
** CAPI3REF: Convenience Routines For Running Queries
|
|
**
|
|
** This next routine is a convenience wrapper around [sqlite3_exec()].
|
|
** Instead of invoking a user-supplied callback for each row of the
|
|
** result, this routine remembers each row of the result in memory
|
|
** obtained from [sqlite3_malloc()], then returns all of the result after the
|
|
** query has finished.
|
|
**
|
|
** As an example, suppose the query result where this table:
|
|
**
|
|
** <blockquote><pre>
|
|
** Name | Age
|
|
** -----------------------
|
|
** Alice | 43
|
|
** Bob | 28
|
|
** Cindy | 21
|
|
** </pre></blockquote>
|
|
**
|
|
** If the 3rd argument were &azResult then after the function returns
|
|
** azResult will contain the following data:
|
|
**
|
|
** <blockquote><pre>
|
|
** azResult[0] = "Name";
|
|
** azResult[1] = "Age";
|
|
** azResult[2] = "Alice";
|
|
** azResult[3] = "43";
|
|
** azResult[4] = "Bob";
|
|
** azResult[5] = "28";
|
|
** azResult[6] = "Cindy";
|
|
** azResult[7] = "21";
|
|
** </pre></blockquote>
|
|
**
|
|
** Notice that there is an extra row of data containing the column
|
|
** headers. But the *nrow return value is still 3. *ncolumn is
|
|
** set to 2. In general, the number of values inserted into azResult
|
|
** will be ((*nrow) + 1)*(*ncolumn).
|
|
**
|
|
** After the calling function has finished using the result, it should
|
|
** pass the result data pointer to sqlite3_free_table() in order to
|
|
** release the memory that was malloc-ed. Because of the way the
|
|
** [sqlite3_malloc()] happens, the calling function must not try to call
|
|
** [sqlite3_free()] directly. Only [sqlite3_free_table()] is able to release
|
|
** the memory properly and safely.
|
|
**
|
|
** The return value of this routine is the same as from [sqlite3_exec()].
|
|
*/
|
|
int sqlite3_get_table(
|
|
sqlite3*, /* An open database */
|
|
const char *sql, /* SQL to be executed */
|
|
char ***resultp, /* Result written to a char *[] that this points to */
|
|
int *nrow, /* Number of result rows written here */
|
|
int *ncolumn, /* Number of result columns written here */
|
|
char **errmsg /* Error msg written here */
|
|
);
|
|
void sqlite3_free_table(char **result);
|
|
|
|
/*
|
|
** CAPI3REF: Formatted String Printing Functions
|
|
**
|
|
** These routines are workalikes of the "printf()" family of functions
|
|
** from the standard C library.
|
|
**
|
|
** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
|
|
** results into memory obtained from [sqlite3_malloc()].
|
|
** The strings returned by these two routines should be
|
|
** released by [sqlite3_free()]. Both routines return a
|
|
** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
|
|
** memory to hold the resulting string.
|
|
**
|
|
** In sqlite3_snprintf() routine is similar to "snprintf()" from
|
|
** the standard C library. The result is written into the
|
|
** buffer supplied as the second parameter whose size is given by
|
|
** the first parameter. Note that the order of the
|
|
** first two parameters is reversed from snprintf(). This is an
|
|
** historical accident that cannot be fixed without breaking
|
|
** backwards compatibility. Note also that sqlite3_snprintf()
|
|
** returns a pointer to its buffer instead of the number of
|
|
** characters actually written into the buffer. We admit that
|
|
** the number of characters written would be a more useful return
|
|
** value but we cannot change the implementation of sqlite3_snprintf()
|
|
** now without breaking compatibility.
|
|
**
|
|
** As long as the buffer size is greater than zero, sqlite3_snprintf()
|
|
** guarantees that the buffer is always zero-terminated. The first
|
|
** parameter "n" is the total size of the buffer, including space for
|
|
** the zero terminator. So the longest string that can be completely
|
|
** written will be n-1 characters.
|
|
**
|
|
** These routines all implement some additional formatting
|
|
** options that are useful for constructing SQL statements.
|
|
** All of the usual printf formatting options apply. In addition, there
|
|
** is are "%q", "%Q", and "%z" options.
|
|
**
|
|
** The %q option works like %s in that it substitutes a null-terminated
|
|
** string from the argument list. But %q also doubles every '\'' character.
|
|
** %q is designed for use inside a string literal. By doubling each '\''
|
|
** character it escapes that character and allows it to be inserted into
|
|
** the string.
|
|
**
|
|
** For example, so some string variable contains text as follows:
|
|
**
|
|
** <blockquote><pre>
|
|
** char *zText = "It's a happy day!";
|
|
** </pre></blockquote>
|
|
**
|
|
** One can use this text in an SQL statement as follows:
|
|
**
|
|
** <blockquote><pre>
|
|
** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
|
|
** sqlite3_exec(db, zSQL, 0, 0, 0);
|
|
** sqlite3_free(zSQL);
|
|
** </pre></blockquote>
|
|
**
|
|
** Because the %q format string is used, the '\'' character in zText
|
|
** is escaped and the SQL generated is as follows:
|
|
**
|
|
** <blockquote><pre>
|
|
** INSERT INTO table1 VALUES('It''s a happy day!')
|
|
** </pre></blockquote>
|
|
**
|
|
** This is correct. Had we used %s instead of %q, the generated SQL
|
|
** would have looked like this:
|
|
**
|
|
** <blockquote><pre>
|
|
** INSERT INTO table1 VALUES('It's a happy day!');
|
|
** </pre></blockquote>
|
|
**
|
|
** This second example is an SQL syntax error. As a general rule you
|
|
** should always use %q instead of %s when inserting text into a string
|
|
** literal.
|
|
**
|
|
** The %Q option works like %q except it also adds single quotes around
|
|
** the outside of the total string. Or if the parameter in the argument
|
|
** list is a NULL pointer, %Q substitutes the text "NULL" (without single
|
|
** quotes) in place of the %Q option. So, for example, one could say:
|
|
**
|
|
** <blockquote><pre>
|
|
** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
|
|
** sqlite3_exec(db, zSQL, 0, 0, 0);
|
|
** sqlite3_free(zSQL);
|
|
** </pre></blockquote>
|
|
**
|
|
** The code above will render a correct SQL statement in the zSQL
|
|
** variable even if the zText variable is a NULL pointer.
|
|
**
|
|
** The "%z" formatting option works exactly like "%s" with the
|
|
** addition that after the string has been read and copied into
|
|
** the result, [sqlite3_free()] is called on the input string.
|
|
*/
|
|
char *sqlite3_mprintf(const char*,...);
|
|
char *sqlite3_vmprintf(const char*, va_list);
|
|
char *sqlite3_snprintf(int,char*,const char*, ...);
|
|
|
|
/*
|
|
** CAPI3REF: Memory Allocation Subsystem
|
|
**
|
|
** The SQLite core uses these three routines for all of its own
|
|
** internal memory allocation needs. (See the exception below.)
|
|
** The default implementation
|
|
** of the memory allocation subsystem uses the malloc(), realloc()
|
|
** and free() provided by the standard C library. However, if
|
|
** SQLite is compiled with the following C preprocessor macro
|
|
**
|
|
** <blockquote> SQLITE_OMIT_MEMORY_ALLOCATION </blockquote>
|
|
**
|
|
** then no implementation is provided for these routines by
|
|
** SQLite. The application that links against SQLite is
|
|
** expected to provide its own implementation. If the application
|
|
** does provide its own implementation for these routines, then
|
|
** it must also provide an implementations for
|
|
** [sqlite3_memory_alarm()], [sqlite3_memory_used()], and
|
|
** [sqlite3_memory_highwater()]. The alternative implementations
|
|
** for these last three routines need not actually work, but
|
|
** stub functions at least are needed to statisfy the linker.
|
|
** SQLite never calls [sqlite3_memory_highwater()] itself, but
|
|
** the symbol is included in a table as part of the
|
|
** [sqlite3_load_extension()] interface. The
|
|
** [sqlite3_memory_alarm()] and [sqlite3_memory_used()] interfaces
|
|
** are called by [sqlite3_soft_heap_limit()] and working implementations
|
|
** of both routines must be provided if [sqlite3_soft_heap_limit()]
|
|
** is to operate correctly.
|
|
**
|
|
** <b>Exception:</b> The windows OS interface layer calls
|
|
** the system malloc() and free() directly when converting
|
|
** filenames between the UTF-8 encoding used by SQLite
|
|
** and whatever filename encoding is used by the particular windows
|
|
** installation. Memory allocation errors are detected, but
|
|
** they are reported back as [SQLITE_CANTOPEN] or
|
|
** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
|
|
*/
|
|
void *sqlite3_malloc(int);
|
|
void *sqlite3_realloc(void*, int);
|
|
void sqlite3_free(void*);
|
|
|
|
/*
|
|
** CAPI3REF: Memory Allocator Statistics
|
|
**
|
|
** In addition to the basic three allocation routines
|
|
** [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()],
|
|
** the memory allocation subsystem included with the SQLite
|
|
** sources provides the interfaces shown below.
|
|
**
|
|
** The first of these two routines returns the amount of memory
|
|
** currently outstanding (malloced but not freed). The second
|
|
** returns the largest instantaneous amount of outstanding
|
|
** memory. The highwater mark is reset if the argument is
|
|
** true.
|
|
**
|
|
** The implementation of these routines in the SQLite core
|
|
** is omitted if the application is compiled with the
|
|
** SQLITE_OMIT_MEMORY_ALLOCATION macro defined. In that case,
|
|
** the application that links SQLite must provide its own
|
|
** alternative implementation. See the documentation on
|
|
** [sqlite3_malloc()] for additional information.
|
|
*/
|
|
sqlite3_int64 sqlite3_memory_used(void);
|
|
sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
|
|
|
|
/*
|
|
** CAPI3REF: Memory Allocation Alarms
|
|
**
|
|
** The [sqlite3_memory_alarm] routine is used to register
|
|
** a callback on memory allocation events.
|
|
**
|
|
** This routine registers or clears a callbacks that fires when
|
|
** the amount of memory allocated exceeds iThreshold. Only
|
|
** a single callback can be registered at a time. Each call
|
|
** to [sqlite3_memory_alarm()] overwrites the previous callback.
|
|
** The callback is disabled by setting xCallback to a NULL
|
|
** pointer.
|
|
**
|
|
** The parameters to the callback are the pArg value, the
|
|
** amount of memory currently in use, and the size of the
|
|
** allocation that provoked the callback. The callback will
|
|
** presumably invoke [sqlite3_free()] to free up memory space.
|
|
** The callback may invoke [sqlite3_malloc()] or [sqlite3_realloc()]
|
|
** but if it does, no additional callbacks will be invoked by
|
|
** the recursive calls.
|
|
**
|
|
** The [sqlite3_soft_heap_limit()] interface works by registering
|
|
** a memory alarm at the soft heap limit and invoking
|
|
** [sqlite3_release_memory()] in the alarm callback. Application
|
|
** programs should not attempt to use the [sqlite3_memory_alarm()]
|
|
** interface because doing so will interfere with the
|
|
** [sqlite3_soft_heap_limit()] module. This interface is exposed
|
|
** only so that applications can provide their own
|
|
** alternative implementation when the SQLite core is
|
|
** compiled with SQLITE_OMIT_MEMORY_ALLOCATION.
|
|
*/
|
|
int sqlite3_memory_alarm(
|
|
void(*xCallback)(void *pArg, sqlite3_int64 used, int N),
|
|
void *pArg,
|
|
sqlite3_int64 iThreshold
|
|
);
|
|
|
|
|
|
/*
|
|
** CAPI3REF: Compile-Time Authorization Callbacks
|
|
***
|
|
** This routine registers a authorizer callback with the SQLite library.
|
|
** The authorizer callback is invoked as SQL statements are being compiled
|
|
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
|
|
** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. At various
|
|
** points during the compilation process, as logic is being created
|
|
** to perform various actions, the authorizer callback is invoked to
|
|
** see if those actions are allowed. The authorizer callback should
|
|
** return SQLITE_OK to allow the action, [SQLITE_IGNORE] to disallow the
|
|
** specific action but allow the SQL statement to continue to be
|
|
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
|
|
** rejected with an error.
|
|
**
|
|
** Depending on the action, the [SQLITE_IGNORE] and [SQLITE_DENY] return
|
|
** codes might mean something different or they might mean the same
|
|
** thing. If the action is, for example, to perform a delete opertion,
|
|
** then [SQLITE_IGNORE] and [SQLITE_DENY] both cause the statement compilation
|
|
** to fail with an error. But if the action is to read a specific column
|
|
** from a specific table, then [SQLITE_DENY] will cause the entire
|
|
** statement to fail but [SQLITE_IGNORE] will cause a NULL value to be
|
|
** read instead of the actual column value.
|
|
**
|
|
** The first parameter to the authorizer callback is a copy of
|
|
** the third parameter to the sqlite3_set_authorizer() interface.
|
|
** The second parameter to the callback is an integer
|
|
** [SQLITE_COPY | action code] that specifies the particular action
|
|
** to be authorized. The available action codes are
|
|
** [SQLITE_COPY | documented separately]. The third through sixth
|
|
** parameters to the callback are strings that contain additional
|
|
** details about the action to be authorized.
|
|
**
|
|
** An authorizer is used when preparing SQL statements from an untrusted
|
|
** source, to ensure that the SQL statements do not try to access data
|
|
** that they are not allowed to see, or that they do not try to
|
|
** execute malicious statements that damage the database. For
|
|
** example, an application may allow a user to enter arbitrary
|
|
** SQL queries for evaluation by a database. But the application does
|
|
** not want the user to be able to make arbitrary changes to the
|
|
** database. An authorizer could then be put in place while the
|
|
** user-entered SQL is being prepared that disallows everything
|
|
** except SELECT statements.
|
|
**
|
|
** Only a single authorizer can be in place on a database connection
|
|
** at a time. Each call to sqlite3_set_authorizer overrides the
|
|
** previous call. A NULL authorizer means that no authorization
|
|
** callback is invoked. The default authorizer is NULL.
|
|
**
|
|
** Note that the authorizer callback is invoked only during
|
|
** [sqlite3_prepare()] or its variants. Authorization is not
|
|
** performed during statement evaluation in [sqlite3_step()].
|
|
*/
|
|
int sqlite3_set_authorizer(
|
|
sqlite3*,
|
|
int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
|
|
void *pUserData
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Authorizer Return Codes
|
|
**
|
|
** The [sqlite3_set_authorizer | authorizer callback function] must
|
|
** return either [SQLITE_OK] or one of these two constants in order
|
|
** to signal SQLite whether or not the action is permitted. See the
|
|
** [sqlite3_set_authorizer | authorizer documentation] for additional
|
|
** information.
|
|
*/
|
|
#define SQLITE_DENY 1 /* Abort the SQL statement with an error */
|
|
#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
|
|
|
|
/*
|
|
** CAPI3REF: Authorizer Action Codes
|
|
**
|
|
** The [sqlite3_set_authorizer()] interface registers a callback function
|
|
** that is invoked to authorizer certain SQL statement actions. The
|
|
** second parameter to the callback is an integer code that specifies
|
|
** what action is being authorized. These are the integer action codes that
|
|
** the authorizer callback may be passed.
|
|
**
|
|
** These action code values signify what kind of operation is to be
|
|
** authorized. The 3rd and 4th parameters to the authorization callback
|
|
** function will be parameters or NULL depending on which of these
|
|
** codes is used as the second parameter. The 5th parameter to the
|
|
** authorizer callback is the name of the database ("main", "temp",
|
|
** etc.) if applicable. The 6th parameter to the authorizer callback
|
|
** is the name of the inner-most trigger or view that is responsible for
|
|
** the access attempt or NULL if this access attempt is directly from
|
|
** top-level SQL code.
|
|
*/
|
|
/******************************************* 3rd ************ 4th ***********/
|
|
#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
|
|
#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
|
|
#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
|
|
#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
|
|
#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
|
|
#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
|
|
#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
|
|
#define SQLITE_CREATE_VIEW 8 /* View Name NULL */
|
|
#define SQLITE_DELETE 9 /* Table Name NULL */
|
|
#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
|
|
#define SQLITE_DROP_TABLE 11 /* Table Name NULL */
|
|
#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
|
|
#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
|
|
#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
|
|
#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
|
|
#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
|
|
#define SQLITE_DROP_VIEW 17 /* View Name NULL */
|
|
#define SQLITE_INSERT 18 /* Table Name NULL */
|
|
#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
|
|
#define SQLITE_READ 20 /* Table Name Column Name */
|
|
#define SQLITE_SELECT 21 /* NULL NULL */
|
|
#define SQLITE_TRANSACTION 22 /* NULL NULL */
|
|
#define SQLITE_UPDATE 23 /* Table Name Column Name */
|
|
#define SQLITE_ATTACH 24 /* Filename NULL */
|
|
#define SQLITE_DETACH 25 /* Database Name NULL */
|
|
#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
|
|
#define SQLITE_REINDEX 27 /* Index Name NULL */
|
|
#define SQLITE_ANALYZE 28 /* Table Name NULL */
|
|
#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
|
|
#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
|
|
#define SQLITE_FUNCTION 31 /* Function Name NULL */
|
|
#define SQLITE_COPY 0 /* No longer used */
|
|
|
|
/*
|
|
** CAPI3REF: Tracing And Profiling Functions
|
|
**
|
|
** These routines register callback functions that can be used for
|
|
** tracing and profiling the execution of SQL statements.
|
|
** The callback function registered by sqlite3_trace() is invoked
|
|
** at the first [sqlite3_step()] for the evaluation of an SQL statement.
|
|
** The callback function registered by sqlite3_profile() is invoked
|
|
** as each SQL statement finishes and includes
|
|
** information on how long that statement ran.
|
|
**
|
|
** The sqlite3_profile() API is currently considered experimental and
|
|
** is subject to change.
|
|
*/
|
|
void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
|
|
void *sqlite3_profile(sqlite3*,
|
|
void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
|
|
|
|
/*
|
|
** CAPI3REF: Query Progress Callbacks
|
|
**
|
|
** This routine configures a callback function - the progress callback - that
|
|
** is invoked periodically during long running calls to [sqlite3_exec()],
|
|
** [sqlite3_step()] and [sqlite3_get_table()]. An example use for this
|
|
** interface is to keep a GUI updated during a large query.
|
|
**
|
|
** The progress callback is invoked once for every N virtual machine opcodes,
|
|
** where N is the second argument to this function. The progress callback
|
|
** itself is identified by the third argument to this function. The fourth
|
|
** argument to this function is a void pointer passed to the progress callback
|
|
** function each time it is invoked.
|
|
**
|
|
** If a call to [sqlite3_exec()], [sqlite3_step()], or [sqlite3_get_table()]
|
|
** results in fewer than N opcodes being executed, then the progress
|
|
** callback is never invoked.
|
|
**
|
|
** Only a single progress callback function may be registered for each
|
|
** open database connection. Every call to sqlite3_progress_handler()
|
|
** overwrites the results of the previous call.
|
|
** To remove the progress callback altogether, pass NULL as the third
|
|
** argument to this function.
|
|
**
|
|
** If the progress callback returns a result other than 0, then the current
|
|
** query is immediately terminated and any database changes rolled back.
|
|
** The containing [sqlite3_exec()], [sqlite3_step()], or
|
|
** [sqlite3_get_table()] call returns SQLITE_INTERRUPT. This feature
|
|
** can be used, for example, to implement the "Cancel" button on a
|
|
** progress dialog box in a GUI.
|
|
*/
|
|
void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
|
|
|
|
/*
|
|
** CAPI3REF: Opening A New Database Connection
|
|
**
|
|
** Open the sqlite database file "filename". The "filename" is UTF-8
|
|
** encoded for [sqlite3_open()] and [sqlite3_open_v2()] and UTF-16 encoded
|
|
** in the native byte order for [sqlite3_open16()].
|
|
** An [sqlite3*] handle is returned in *ppDb, even
|
|
** if an error occurs. If the database is opened (or created) successfully,
|
|
** then [SQLITE_OK] is returned. Otherwise an error code is returned. The
|
|
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
|
|
** an English language description of the error.
|
|
**
|
|
** The default encoding for the database will be UTF-8 if
|
|
** [sqlite3_open()] or [sqlite3_open_v2()] is called and
|
|
** UTF-16 if [sqlite3_open16()] is used.
|
|
**
|
|
** Whether or not an error occurs when it is opened, resources associated
|
|
** with the [sqlite3*] handle should be released by passing it to
|
|
** [sqlite3_close()] when it is no longer required.
|
|
**
|
|
** The [sqlite3_open_v2()] interface works like [sqlite3_open()] except that
|
|
** provides two additional parameters for additional control over the
|
|
** new database connection. The flags parameter can be one of:
|
|
**
|
|
** <ol>
|
|
** <li> [SQLITE_OPEN_READONLY]
|
|
** <li> [SQLITE_OPEN_READWRITE]
|
|
** <li> [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
|
|
** </ol>
|
|
**
|
|
** The first value opens the database read-only. If the database does
|
|
** not previously exist, an error is returned. The second option opens
|
|
** the database for reading and writing if possible, or reading only if
|
|
** if the file is write protected. In either case the database must already
|
|
** exist or an error is returned. The third option opens the database
|
|
** for reading and writing and creates it if it does not already exist.
|
|
** The third options is behavior that is always used for [sqlite3_open()]
|
|
** and [sqlite3_open16()].
|
|
**
|
|
** If the filename is ":memory:", then an private
|
|
** in-memory database is created for the connection. This in-memory
|
|
** database will vanish when the database connection is closed. Future
|
|
** version of SQLite might make use of additional special filenames
|
|
** that begin with the ":" character. It is recommended that
|
|
** when a database filename really does begin with
|
|
** ":" that you prefix the filename with a pathname like "./" to
|
|
** avoid ambiguity.
|
|
**
|
|
** If the filename is an empty string, then a private temporary
|
|
** on-disk database will be created. This private database will be
|
|
** automatically deleted as soon as the database connection is closed.
|
|
**
|
|
** The fourth parameter to sqlite3_open_v2() is the name of the
|
|
** [sqlite3_vfs] object that defines the operating system
|
|
** interface that the new database connection should use. If the
|
|
** fourth parameter is a NULL pointer then the default [sqlite3_vfs]
|
|
** object is used.
|
|
**
|
|
** <b>Note to windows users:</b> The encoding used for the filename argument
|
|
** of [sqlite3_open()] and [sqlite3_open_v2()] must be UTF-8, not whatever
|
|
** codepage is currently defined. Filenames containing international
|
|
** characters must be converted to UTF-8 prior to passing them into
|
|
** [sqlite3_open()] or [sqlite3_open_v2()].
|
|
*/
|
|
int sqlite3_open(
|
|
const char *filename, /* Database filename (UTF-8) */
|
|
sqlite3 **ppDb /* OUT: SQLite db handle */
|
|
);
|
|
int sqlite3_open16(
|
|
const void *filename, /* Database filename (UTF-16) */
|
|
sqlite3 **ppDb /* OUT: SQLite db handle */
|
|
);
|
|
int sqlite3_open_v2(
|
|
const char *filename, /* Database filename (UTF-8) */
|
|
sqlite3 **ppDb, /* OUT: SQLite db handle */
|
|
int flags, /* Flags */
|
|
const char *zVfs /* Name of VFS module to use */
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Error Codes And Messages
|
|
**
|
|
** The sqlite3_errcode() interface returns the numeric
|
|
** [SQLITE_OK | result code] or [SQLITE_IOERR_READ | extended result code]
|
|
** for the most recent failed sqlite3_* API call associated
|
|
** with [sqlite3] handle 'db'. If a prior API call failed but the
|
|
** most recent API call succeeded, the return value from sqlite3_errcode()
|
|
** is undefined.
|
|
**
|
|
** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
|
|
** text that describes the error, as either UTF8 or UTF16 respectively.
|
|
** Memory to hold the error message string is managed internally. The
|
|
** string may be overwritten or deallocated by subsequent calls to SQLite
|
|
** interface functions.
|
|
**
|
|
** Calls to many sqlite3_* functions set the error code and string returned
|
|
** by [sqlite3_errcode()], [sqlite3_errmsg()], and [sqlite3_errmsg16()]
|
|
** (overwriting the previous values). Note that calls to [sqlite3_errcode()],
|
|
** [sqlite3_errmsg()], and [sqlite3_errmsg16()] themselves do not affect the
|
|
** results of future invocations. Calls to API routines that do not return
|
|
** an error code (example: [sqlite3_data_count()]) do not
|
|
** change the error code returned by this routine. Interfaces that are
|
|
** not associated with a specific database connection (examples:
|
|
** [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()] do not change
|
|
** the return code.
|
|
**
|
|
** Assuming no other intervening sqlite3_* API calls are made, the error
|
|
** code returned by this function is associated with the same error as
|
|
** the strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()].
|
|
*/
|
|
int sqlite3_errcode(sqlite3 *db);
|
|
const char *sqlite3_errmsg(sqlite3*);
|
|
const void *sqlite3_errmsg16(sqlite3*);
|
|
|
|
/*
|
|
** CAPI3REF: SQL Statement Object
|
|
**
|
|
** Instance of this object represent single SQL statements. This
|
|
** is variously known as a "prepared statement" or a
|
|
** "compiled SQL statement" or simply as a "statement".
|
|
**
|
|
** The life of a statement object goes something like this:
|
|
**
|
|
** <ol>
|
|
** <li> Create the object using [sqlite3_prepare_v2()] or a related
|
|
** function.
|
|
** <li> Bind values to host parameters using
|
|
** [sqlite3_bind_blob | sqlite3_bind_* interfaces].
|
|
** <li> Run the SQL by calling [sqlite3_step()] one or more times.
|
|
** <li> Reset the statement using [sqlite3_reset()] then go back
|
|
** to step 2. Do this zero or more times.
|
|
** <li> Destroy the object using [sqlite3_finalize()].
|
|
** </ol>
|
|
**
|
|
** Refer to documentation on individual methods above for additional
|
|
** information.
|
|
*/
|
|
typedef struct sqlite3_stmt sqlite3_stmt;
|
|
|
|
/*
|
|
** CAPI3REF: Compiling An SQL Statement
|
|
**
|
|
** To execute an SQL query, it must first be compiled into a byte-code
|
|
** program using one of these routines.
|
|
**
|
|
** The first argument "db" is an [sqlite3 | SQLite database handle]
|
|
** obtained from a prior call to [sqlite3_open()], [sqlite3_open_v2()]
|
|
** or [sqlite3_open16()].
|
|
** The second argument "zSql" is the statement to be compiled, encoded
|
|
** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
|
|
** interfaces uses UTF-8 and sqlite3_prepare16() and sqlite3_prepare16_v2()
|
|
** use UTF-16.
|
|
**
|
|
** If the nByte argument is less
|
|
** than zero, then zSql is read up to the first zero terminator. If
|
|
** nByte is non-negative, then it is the maximum number of
|
|
** bytes read from zSql. When nByte is non-negative, the
|
|
** zSql string ends at either the first '\000' character or
|
|
** until the nByte-th byte, whichever comes first.
|
|
**
|
|
** *pzTail is made to point to the first byte past the end of the first
|
|
** SQL statement in zSql. This routine only compiles the first statement
|
|
** in zSql, so *pzTail is left pointing to what remains uncompiled.
|
|
**
|
|
** *ppStmt is left pointing to a compiled
|
|
** [sqlite3_stmt | SQL statement structure] that can be
|
|
** executed using [sqlite3_step()]. Or if there is an error, *ppStmt may be
|
|
** set to NULL. If the input text contained no SQL (if the input is and
|
|
** empty string or a comment) then *ppStmt is set to NULL. The calling
|
|
** procedure is responsible for deleting the compiled SQL statement
|
|
** using [sqlite3_finalize()] after it has finished with it.
|
|
**
|
|
** On success, [SQLITE_OK] is returned. Otherwise an
|
|
** [SQLITE_ERROR | error code] is returned.
|
|
**
|
|
** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
|
|
** recommended for all new programs. The two older interfaces are retained
|
|
** for backwards compatibility, but their use is discouraged.
|
|
** In the "v2" interfaces, the prepared statement
|
|
** that is returned (the [sqlite3_stmt] object) contains a copy of the
|
|
** original SQL text. This causes the [sqlite3_step()] interface to
|
|
** behave a differently in two ways:
|
|
**
|
|
** <ol>
|
|
** <li>
|
|
** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
|
|
** always used to do, [sqlite3_step()] will automatically recompile the SQL
|
|
** statement and try to run it again. If the schema has changed in a way
|
|
** that makes the statement no longer valid, [sqlite3_step()] will still
|
|
** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is
|
|
** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the
|
|
** error go away. Note: use [sqlite3_errmsg()] to find the text of the parsing
|
|
** error that results in an [SQLITE_SCHEMA] return.
|
|
** </li>
|
|
**
|
|
** <li>
|
|
** When an error occurs,
|
|
** [sqlite3_step()] will return one of the detailed
|
|
** [SQLITE_ERROR | result codes] or
|
|
** [SQLITE_IOERR_READ | extended result codes] such as directly.
|
|
** The legacy behavior was that [sqlite3_step()] would only return a generic
|
|
** [SQLITE_ERROR] result code and you would have to make a second call to
|
|
** [sqlite3_reset()] in order to find the underlying cause of the problem.
|
|
** With the "v2" prepare interfaces, the underlying reason for the error is
|
|
** returned immediately.
|
|
** </li>
|
|
** </ol>
|
|
*/
|
|
int sqlite3_prepare(
|
|
sqlite3 *db, /* Database handle */
|
|
const char *zSql, /* SQL statement, UTF-8 encoded */
|
|
int nByte, /* Maximum length of zSql in bytes. */
|
|
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
|
|
const char **pzTail /* OUT: Pointer to unused portion of zSql */
|
|
);
|
|
int sqlite3_prepare_v2(
|
|
sqlite3 *db, /* Database handle */
|
|
const char *zSql, /* SQL statement, UTF-8 encoded */
|
|
int nByte, /* Maximum length of zSql in bytes. */
|
|
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
|
|
const char **pzTail /* OUT: Pointer to unused portion of zSql */
|
|
);
|
|
int sqlite3_prepare16(
|
|
sqlite3 *db, /* Database handle */
|
|
const void *zSql, /* SQL statement, UTF-16 encoded */
|
|
int nByte, /* Maximum length of zSql in bytes. */
|
|
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
|
|
const void **pzTail /* OUT: Pointer to unused portion of zSql */
|
|
);
|
|
int sqlite3_prepare16_v2(
|
|
sqlite3 *db, /* Database handle */
|
|
const void *zSql, /* SQL statement, UTF-16 encoded */
|
|
int nByte, /* Maximum length of zSql in bytes. */
|
|
sqlite3_stmt **ppStmt, /* OUT: Statement handle */
|
|
const void **pzTail /* OUT: Pointer to unused portion of zSql */
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Dynamically Typed Value Object
|
|
**
|
|
** SQLite uses dynamic typing for the values it stores. Values can
|
|
** be integers, floating point values, strings, BLOBs, or NULL. When
|
|
** passing around values internally, each value is represented as
|
|
** an instance of the sqlite3_value object.
|
|
*/
|
|
typedef struct Mem sqlite3_value;
|
|
|
|
/*
|
|
** CAPI3REF: SQL Function Context Object
|
|
**
|
|
** The context in which an SQL function executes is stored in an
|
|
** sqlite3_context object. A pointer to such an object is the
|
|
** first parameter to user-defined SQL functions.
|
|
*/
|
|
typedef struct sqlite3_context sqlite3_context;
|
|
|
|
/*
|
|
** CAPI3REF: Binding Values To Prepared Statements
|
|
**
|
|
** In the SQL strings input to [sqlite3_prepare_v2()] and its variants,
|
|
** one or more literals can be replace by a parameter in one of these
|
|
** forms:
|
|
**
|
|
** <ul>
|
|
** <li> ?
|
|
** <li> ?NNN
|
|
** <li> :AAA
|
|
** <li> @AAA
|
|
** <li> $VVV
|
|
** </ul>
|
|
**
|
|
** In the parameter forms shown above NNN is an integer literal,
|
|
** AAA is an alphanumeric identifier and VVV is a variable name according
|
|
** to the syntax rules of the TCL programming language.
|
|
** The values of these parameters (also called "host parameter names")
|
|
** can be set using the sqlite3_bind_*() routines defined here.
|
|
**
|
|
** The first argument to the sqlite3_bind_*() routines always is a pointer
|
|
** to the [sqlite3_stmt] object returned from [sqlite3_prepare_v2()] or
|
|
** its variants. The second
|
|
** argument is the index of the parameter to be set. The first parameter has
|
|
** an index of 1. When the same named parameter is used more than once, second
|
|
** and subsequent
|
|
** occurrences have the same index as the first occurrence. The index for
|
|
** named parameters can be looked up using the
|
|
** [sqlite3_bind_parameter_name()] API if desired. The index for "?NNN"
|
|
** parametes is the value of NNN.
|
|
** The NNN value must be between 1 and the compile-time
|
|
** parameter SQLITE_MAX_VARIABLE_NUMBER (default value: 999).
|
|
** See <a href="limits.html">limits.html</a> for additional information.
|
|
**
|
|
** The third argument is the value to bind to the parameter.
|
|
**
|
|
** In those
|
|
** routines that have a fourth argument, its value is the number of bytes
|
|
** in the parameter. To be clear: the value is the number of bytes in the
|
|
** string, not the number of characters. The number
|
|
** of bytes does not include the zero-terminator at the end of strings.
|
|
** If the fourth parameter is negative, the length of the string is
|
|
** number of bytes up to the first zero terminator.
|
|
**
|
|
** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
|
|
** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
|
|
** text after SQLite has finished with it. If the fifth argument is the
|
|
** special value [SQLITE_STATIC], then the library assumes that the information
|
|
** is in static, unmanaged space and does not need to be freed. If the
|
|
** fifth argument has the value [SQLITE_TRANSIENT], then SQLite makes its
|
|
** own private copy of the data immediately, before the sqlite3_bind_*()
|
|
** routine returns.
|
|
**
|
|
** The sqlite3_bind_zeroblob() routine binds a BLOB of length n that
|
|
** is filled with zeros. A zeroblob uses a fixed amount of memory
|
|
** (just an integer to hold it size) while it is being processed.
|
|
** Zeroblobs are intended to serve as place-holders for BLOBs whose
|
|
** content is later written using
|
|
** [sqlite3_blob_open | increment BLOB I/O] routines. A negative
|
|
** value for the zeroblob results in a zero-length BLOB.
|
|
**
|
|
** The sqlite3_bind_*() routines must be called after
|
|
** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and
|
|
** before [sqlite3_step()].
|
|
** Bindings are not cleared by the [sqlite3_reset()] routine.
|
|
** Unbound parameters are interpreted as NULL.
|
|
**
|
|
** These routines return [SQLITE_OK] on success or an error code if
|
|
** anything goes wrong. [SQLITE_RANGE] is returned if the parameter
|
|
** index is out of range. [SQLITE_NOMEM] is returned if malloc fails.
|
|
** [SQLITE_MISUSE] is returned if these routines are called on a virtual
|
|
** machine that is the wrong state or which has already been finalized.
|
|
*/
|
|
int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
|
|
int sqlite3_bind_double(sqlite3_stmt*, int, double);
|
|
int sqlite3_bind_int(sqlite3_stmt*, int, int);
|
|
int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
|
|
int sqlite3_bind_null(sqlite3_stmt*, int);
|
|
int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
|
|
int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
|
|
int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
|
|
int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
|
|
|
|
/*
|
|
** CAPI3REF: Number Of Host Parameters
|
|
**
|
|
** Return the largest host parameter index in the precompiled statement given
|
|
** as the argument. When the host parameters are of the forms like ":AAA"
|
|
** or "?", then they are assigned sequential increasing numbers beginning
|
|
** with one, so the value returned is the number of parameters. However
|
|
** if the same host parameter name is used multiple times, each occurrance
|
|
** is given the same number, so the value returned in that case is the number
|
|
** of unique host parameter names. If host parameters of the form "?NNN"
|
|
** are used (where NNN is an integer) then there might be gaps in the
|
|
** numbering and the value returned by this interface is the index of the
|
|
** host parameter with the largest index value.
|
|
**
|
|
** The prepared statement must not be [sqlite3_finalize | finalized]
|
|
** prior to this routine returnning. Otherwise the results are undefined
|
|
** and probably undesirable.
|
|
*/
|
|
int sqlite3_bind_parameter_count(sqlite3_stmt*);
|
|
|
|
/*
|
|
** CAPI3REF: Name Of A Host Parameter
|
|
**
|
|
** This routine returns a pointer to the name of the n-th parameter in a
|
|
** [sqlite3_stmt | prepared statement].
|
|
** Host parameters of the form ":AAA" or "@AAA" or "$VVV" have a name
|
|
** which is the string ":AAA" or "@AAA" or "$VVV".
|
|
** In other words, the initial ":" or "$" or "@"
|
|
** is included as part of the name.
|
|
** Parameters of the form "?" or "?NNN" have no name.
|
|
**
|
|
** The first bound parameter has an index of 1, not 0.
|
|
**
|
|
** If the value n is out of range or if the n-th parameter is nameless,
|
|
** then NULL is returned. The returned string is always in the
|
|
** UTF-8 encoding even if the named parameter was originally specified
|
|
** as UTF-16 in [sqlite3_prepare16()] or [sqlite3_prepare16_v2()].
|
|
*/
|
|
const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
|
|
|
|
/*
|
|
** CAPI3REF: Index Of A Parameter With A Given Name
|
|
**
|
|
** This routine returns the index of a host parameter with the given name.
|
|
** The name must match exactly. If no parameter with the given name is
|
|
** found, return 0. Parameter names must be UTF8.
|
|
*/
|
|
int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
|
|
|
|
/*
|
|
** CAPI3REF: Reset All Bindings On A Prepared Statement
|
|
**
|
|
** Contrary to the intuition of many, [sqlite3_reset()] does not
|
|
** reset the [sqlite3_bind_blob | bindings] on a
|
|
** [sqlite3_stmt | prepared statement]. Use this routine to
|
|
** reset all host parameters to NULL.
|
|
*/
|
|
int sqlite3_clear_bindings(sqlite3_stmt*);
|
|
|
|
/*
|
|
** CAPI3REF: Number Of Columns In A Result Set
|
|
**
|
|
** Return the number of columns in the result set returned by the
|
|
** [sqlite3_stmt | compiled SQL statement]. This routine returns 0
|
|
** if pStmt is an SQL statement that does not return data (for
|
|
** example an UPDATE).
|
|
*/
|
|
int sqlite3_column_count(sqlite3_stmt *pStmt);
|
|
|
|
/*
|
|
** CAPI3REF: Column Names In A Result Set
|
|
**
|
|
** These routines return the name assigned to a particular column
|
|
** in the result set of a SELECT statement. The sqlite3_column_name()
|
|
** interface returns a pointer to a UTF8 string and sqlite3_column_name16()
|
|
** returns a pointer to a UTF16 string. The first parameter is the
|
|
** [sqlite3_stmt | prepared statement] that implements the SELECT statement.
|
|
** The second parameter is the column number. The left-most column is
|
|
** number 0.
|
|
**
|
|
** The returned string pointer is valid until either the
|
|
** [sqlite3_stmt | prepared statement] is destroyed by [sqlite3_finalize()]
|
|
** or until the next call sqlite3_column_name() or sqlite3_column_name16()
|
|
** on the same column.
|
|
**
|
|
** If sqlite3_malloc() fails during the processing of either routine
|
|
** (for example during a conversion from UTF-8 to UTF-16) then a
|
|
** NULL pointer is returned.
|
|
*/
|
|
const char *sqlite3_column_name(sqlite3_stmt*, int N);
|
|
const void *sqlite3_column_name16(sqlite3_stmt*, int N);
|
|
|
|
/*
|
|
** CAPI3REF: Source Of Data In A Query Result
|
|
**
|
|
** These routines provide a means to determine what column of what
|
|
** table in which database a result of a SELECT statement comes from.
|
|
** The name of the database or table or column can be returned as
|
|
** either a UTF8 or UTF16 string. The _database_ routines return
|
|
** the database name, the _table_ routines return the table name, and
|
|
** the origin_ routines return the column name.
|
|
** The returned string is valid until
|
|
** the [sqlite3_stmt | prepared statement] is destroyed using
|
|
** [sqlite3_finalize()] or until the same information is requested
|
|
** again in a different encoding.
|
|
**
|
|
** The names returned are the original un-aliased names of the
|
|
** database, table, and column.
|
|
**
|
|
** The first argument to the following calls is a
|
|
** [sqlite3_stmt | compiled SQL statement].
|
|
** These functions return information about the Nth column returned by
|
|
** the statement, where N is the second function argument.
|
|
**
|
|
** If the Nth column returned by the statement is an expression
|
|
** or subquery and is not a column value, then all of these functions
|
|
** return NULL. Otherwise, they return the
|
|
** name of the attached database, table and column that query result
|
|
** column was extracted from.
|
|
**
|
|
** As with all other SQLite APIs, those postfixed with "16" return UTF-16
|
|
** encoded strings, the other functions return UTF-8.
|
|
**
|
|
** These APIs are only available if the library was compiled with the
|
|
** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
|
|
**
|
|
** If two or more threads call one or more of these routines against the same
|
|
** prepared statement and column at the same time then the results are
|
|
** undefined.
|
|
*/
|
|
const char *sqlite3_column_database_name(sqlite3_stmt*,int);
|
|
const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
|
|
const char *sqlite3_column_table_name(sqlite3_stmt*,int);
|
|
const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
|
|
const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
|
|
const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
|
|
|
|
/*
|
|
** CAPI3REF: Declared Datatype Of A Query Result
|
|
**
|
|
** The first parameter is a [sqlite3_stmt | compiled SQL statement].
|
|
** If this statement is a SELECT statement and the Nth column of the
|
|
** returned result set of that SELECT is a table column (not an
|
|
** expression or subquery) then the declared type of the table
|
|
** column is returned. If the Nth column of the result set is an
|
|
** expression or subquery, then a NULL pointer is returned.
|
|
** The returned string is always UTF-8 encoded. For example, in
|
|
** the database schema:
|
|
**
|
|
** CREATE TABLE t1(c1 VARIANT);
|
|
**
|
|
** And the following statement compiled:
|
|
**
|
|
** SELECT c1 + 1, c1 FROM t1;
|
|
**
|
|
** Then this routine would return the string "VARIANT" for the second
|
|
** result column (i==1), and a NULL pointer for the first result column
|
|
** (i==0).
|
|
**
|
|
** SQLite uses dynamic run-time typing. So just because a column
|
|
** is declared to contain a particular type does not mean that the
|
|
** data stored in that column is of the declared type. SQLite is
|
|
** strongly typed, but the typing is dynamic not static. Type
|
|
** is associated with individual values, not with the containers
|
|
** used to hold those values.
|
|
*/
|
|
const char *sqlite3_column_decltype(sqlite3_stmt *, int i);
|
|
const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
|
|
|
|
/*
|
|
** CAPI3REF: Evaluate An SQL Statement
|
|
**
|
|
** After an [sqlite3_stmt | SQL statement] has been prepared with a call
|
|
** to either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or to one of
|
|
** the legacy interfaces [sqlite3_prepare()] or [sqlite3_prepare16()],
|
|
** then this function must be called one or more times to evaluate the
|
|
** statement.
|
|
**
|
|
** The details of the behavior of this sqlite3_step() interface depend
|
|
** on whether the statement was prepared using the newer "v2" interface
|
|
** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
|
|
** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
|
|
** new "v2" interface is recommended for new applications but the legacy
|
|
** interface will continue to be supported.
|
|
**
|
|
** In the lagacy interface, the return value will be either [SQLITE_BUSY],
|
|
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
|
|
** With the "v2" interface, any of the other [SQLITE_OK | result code]
|
|
** or [SQLITE_IOERR_READ | extended result code] might be returned as
|
|
** well.
|
|
**
|
|
** [SQLITE_BUSY] means that the database engine was unable to acquire the
|
|
** database locks it needs to do its job. If the statement is a COMMIT
|
|
** or occurs outside of an explicit transaction, then you can retry the
|
|
** statement. If the statement is not a COMMIT and occurs within a
|
|
** explicit transaction then you should rollback the transaction before
|
|
** continuing.
|
|
**
|
|
** [SQLITE_DONE] means that the statement has finished executing
|
|
** successfully. sqlite3_step() should not be called again on this virtual
|
|
** machine without first calling [sqlite3_reset()] to reset the virtual
|
|
** machine back to its initial state.
|
|
**
|
|
** If the SQL statement being executed returns any data, then
|
|
** [SQLITE_ROW] is returned each time a new row of data is ready
|
|
** for processing by the caller. The values may be accessed using
|
|
** the [sqlite3_column_int | column access functions].
|
|
** sqlite3_step() is called again to retrieve the next row of data.
|
|
**
|
|
** [SQLITE_ERROR] means that a run-time error (such as a constraint
|
|
** violation) has occurred. sqlite3_step() should not be called again on
|
|
** the VM. More information may be found by calling [sqlite3_errmsg()].
|
|
** With the legacy interface, a more specific error code (example:
|
|
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
|
|
** can be obtained by calling [sqlite3_reset()] on the
|
|
** [sqlite3_stmt | prepared statement]. In the "v2" interface,
|
|
** the more specific error code is returned directly by sqlite3_step().
|
|
**
|
|
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
|
|
** Perhaps it was called on a [sqlite3_stmt | prepared statement] that has
|
|
** already been [sqlite3_finalize | finalized] or on one that had
|
|
** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
|
|
** be the case that the same database connection is being used by two or
|
|
** more threads at the same moment in time.
|
|
**
|
|
** <b>Goofy Interface Alert:</b>
|
|
** In the legacy interface,
|
|
** the sqlite3_step() API always returns a generic error code,
|
|
** [SQLITE_ERROR], following any error other than [SQLITE_BUSY]
|
|
** and [SQLITE_MISUSE]. You must call [sqlite3_reset()] or
|
|
** [sqlite3_finalize()] in order to find one of the specific
|
|
** [SQLITE_ERROR | result codes] that better describes the error.
|
|
** We admit that this is a goofy design. The problem has been fixed
|
|
** with the "v2" interface. If you prepare all of your SQL statements
|
|
** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
|
|
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()], then the
|
|
** more specific [SQLITE_ERROR | result codes] are returned directly
|
|
** by sqlite3_step(). The use of the "v2" interface is recommended.
|
|
*/
|
|
int sqlite3_step(sqlite3_stmt*);
|
|
|
|
/*
|
|
** CAPI3REF:
|
|
**
|
|
** Return the number of values in the current row of the result set.
|
|
**
|
|
** After a call to [sqlite3_step()] that returns [SQLITE_ROW], this routine
|
|
** will return the same value as the [sqlite3_column_count()] function.
|
|
** After [sqlite3_step()] has returned an [SQLITE_DONE], [SQLITE_BUSY], or
|
|
** a [SQLITE_ERROR | error code], or before [sqlite3_step()] has been
|
|
** called on the [sqlite3_stmt | prepared statement] for the first time,
|
|
** this routine returns zero.
|
|
*/
|
|
int sqlite3_data_count(sqlite3_stmt *pStmt);
|
|
|
|
/*
|
|
** CAPI3REF: Fundamental Datatypes
|
|
**
|
|
** Every value in SQLite has one of five fundamental datatypes:
|
|
**
|
|
** <ul>
|
|
** <li> 64-bit signed integer
|
|
** <li> 64-bit IEEE floating point number
|
|
** <li> string
|
|
** <li> BLOB
|
|
** <li> NULL
|
|
** </ul>
|
|
**
|
|
** These constants are codes for each of those types.
|
|
**
|
|
** Note that the SQLITE_TEXT constant was also used in SQLite version 2
|
|
** for a completely different meaning. Software that links against both
|
|
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT not
|
|
** SQLITE_TEXT.
|
|
*/
|
|
#define SQLITE_INTEGER 1
|
|
#define SQLITE_FLOAT 2
|
|
#define SQLITE_BLOB 4
|
|
#define SQLITE_NULL 5
|
|
#ifdef SQLITE_TEXT
|
|
# undef SQLITE_TEXT
|
|
#else
|
|
# define SQLITE_TEXT 3
|
|
#endif
|
|
#define SQLITE3_TEXT 3
|
|
|
|
/*
|
|
** CAPI3REF: Results Values From A Query
|
|
**
|
|
** These routines return information about
|
|
** a single column of the current result row of a query. In every
|
|
** case the first argument is a pointer to the
|
|
** [sqlite3_stmt | SQL statement] that is being
|
|
** evaluated (the [sqlite3_stmt*] that was returned from
|
|
** [sqlite3_prepare_v2()] or one of its variants) and
|
|
** the second argument is the index of the column for which information
|
|
** should be returned. The left-most column of the result set
|
|
** has an index of 0.
|
|
**
|
|
** If the SQL statement is not currently point to a valid row, or if the
|
|
** the column index is out of range, the result is undefined.
|
|
** These routines may only be called when the most recent call to
|
|
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
|
|
** [sqlite3_reset()] nor [sqlite3_finalize()] has been call subsequently.
|
|
** If any of these routines are called after [sqlite3_reset()] or
|
|
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
|
|
** something other than [SQLITE_ROW], the results are undefined.
|
|
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
|
|
** are called from a different thread while any of these routines
|
|
** are pending, then the results are undefined.
|
|
**
|
|
** The sqlite3_column_type() routine returns
|
|
** [SQLITE_INTEGER | datatype code] for the initial data type
|
|
** of the result column. The returned value is one of [SQLITE_INTEGER],
|
|
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
|
|
** returned by sqlite3_column_type() is only meaningful if no type
|
|
** conversions have occurred as described below. After a type conversion,
|
|
** the value returned by sqlite3_column_type() is undefined. Future
|
|
** versions of SQLite may change the behavior of sqlite3_column_type()
|
|
** following a type conversion.
|
|
**
|
|
** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
|
|
** routine returns the number of bytes in that BLOB or string.
|
|
** If the result is a UTF-16 string, then sqlite3_column_bytes() converts
|
|
** the string to UTF-8 and then returns the number of bytes.
|
|
** If the result is a numeric value then sqlite3_column_bytes() uses
|
|
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
|
|
** the number of bytes in that string.
|
|
** The value returned does not include the zero terminator at the end
|
|
** of the string. For clarity: the value returned is the number of
|
|
** bytes in the string, not the number of characters.
|
|
**
|
|
** Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
|
|
** even zero-length strings, are always zero terminated. The return
|
|
** value from sqlite3_column_blob() for a zero-length blob is an arbitrary
|
|
** pointer, possibly even a NULL pointer.
|
|
**
|
|
** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes()
|
|
** but leaves the result in UTF-16 instead of UTF-8.
|
|
** The zero terminator is not included in this count.
|
|
**
|
|
** These routines attempt to convert the value where appropriate. For
|
|
** example, if the internal representation is FLOAT and a text result
|
|
** is requested, [sqlite3_snprintf()] is used internally to do the conversion
|
|
** automatically. The following table details the conversions that
|
|
** are applied:
|
|
**
|
|
** <blockquote>
|
|
** <table border="1">
|
|
** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
|
|
**
|
|
** <tr><td> NULL <td> INTEGER <td> Result is 0
|
|
** <tr><td> NULL <td> FLOAT <td> Result is 0.0
|
|
** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
|
|
** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
|
|
** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
|
|
** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
|
|
** <tr><td> INTEGER <td> BLOB <td> Same as for INTEGER->TEXT
|
|
** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
|
|
** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
|
|
** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
|
|
** <tr><td> TEXT <td> INTEGER <td> Use atoi()
|
|
** <tr><td> TEXT <td> FLOAT <td> Use atof()
|
|
** <tr><td> TEXT <td> BLOB <td> No change
|
|
** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
|
|
** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
|
|
** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
|
|
** </table>
|
|
** </blockquote>
|
|
**
|
|
** The table above makes reference to standard C library functions atoi()
|
|
** and atof(). SQLite does not really use these functions. It has its
|
|
** on equavalent internal routines. The atoi() and atof() names are
|
|
** used in the table for brevity and because they are familiar to most
|
|
** C programmers.
|
|
**
|
|
** Note that when type conversions occur, pointers returned by prior
|
|
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
|
|
** sqlite3_column_text16() may be invalidated.
|
|
** Type conversions and pointer invalidations might occur
|
|
** in the following cases:
|
|
**
|
|
** <ul>
|
|
** <li><p> The initial content is a BLOB and sqlite3_column_text()
|
|
** or sqlite3_column_text16() is called. A zero-terminator might
|
|
** need to be added to the string.</p></li>
|
|
**
|
|
** <li><p> The initial content is UTF-8 text and sqlite3_column_bytes16() or
|
|
** sqlite3_column_text16() is called. The content must be converted
|
|
** to UTF-16.</p></li>
|
|
**
|
|
** <li><p> The initial content is UTF-16 text and sqlite3_column_bytes() or
|
|
** sqlite3_column_text() is called. The content must be converted
|
|
** to UTF-8.</p></li>
|
|
** </ul>
|
|
**
|
|
** Conversions between UTF-16be and UTF-16le are always done in place and do
|
|
** not invalidate a prior pointer, though of course the content of the buffer
|
|
** that the prior pointer points to will have been modified. Other kinds
|
|
** of conversion are done in place when it is possible, but sometime it is
|
|
** not possible and in those cases prior pointers are invalidated.
|
|
**
|
|
** The safest and easiest to remember policy is to invoke these routines
|
|
** in one of the following ways:
|
|
**
|
|
** <ul>
|
|
** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
|
|
** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
|
|
** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
|
|
** </ul>
|
|
**
|
|
** In other words, you should call sqlite3_column_text(), sqlite3_column_blob(),
|
|
** or sqlite3_column_text16() first to force the result into the desired
|
|
** format, then invoke sqlite3_column_bytes() or sqlite3_column_bytes16() to
|
|
** find the size of the result. Do not mix call to sqlite3_column_text() or
|
|
** sqlite3_column_blob() with calls to sqlite3_column_bytes16(). And do not
|
|
** mix calls to sqlite3_column_text16() with calls to sqlite3_column_bytes().
|
|
**
|
|
** The pointers returned are valid until a type conversion occurs as
|
|
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
|
|
** [sqlite3_finalize()] is called. The memory space used to hold strings
|
|
** and blobs is freed automatically. Do <b>not</b> pass the pointers returned
|
|
** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
|
|
** [sqlite3_free()].
|
|
**
|
|
** If a memory allocation error occurs during the evaluation of any
|
|
** of these routines, a default value is returned. The default value
|
|
** is either the integer 0, the floating point number 0.0, or a NULL
|
|
** pointer. Subsequent calls to [sqlite3_errcode()] will return
|
|
** [SQLITE_NOMEM].
|
|
*/
|
|
const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
|
|
int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
|
|
int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
|
|
double sqlite3_column_double(sqlite3_stmt*, int iCol);
|
|
int sqlite3_column_int(sqlite3_stmt*, int iCol);
|
|
sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
|
|
const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
|
|
const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
|
|
int sqlite3_column_type(sqlite3_stmt*, int iCol);
|
|
sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
|
|
|
|
/*
|
|
** CAPI3REF: Destroy A Prepared Statement Object
|
|
**
|
|
** The sqlite3_finalize() function is called to delete a
|
|
** [sqlite3_stmt | compiled SQL statement]. If the statement was
|
|
** executed successfully, or not executed at all, then SQLITE_OK is returned.
|
|
** If execution of the statement failed then an
|
|
** [SQLITE_ERROR | error code] or [SQLITE_IOERR_READ | extended error code]
|
|
** is returned.
|
|
**
|
|
** This routine can be called at any point during the execution of the
|
|
** [sqlite3_stmt | virtual machine]. If the virtual machine has not
|
|
** completed execution when this routine is called, that is like
|
|
** encountering an error or an interrupt. (See [sqlite3_interrupt()].)
|
|
** Incomplete updates may be rolled back and transactions cancelled,
|
|
** depending on the circumstances, and the
|
|
** [SQLITE_ERROR | result code] returned will be [SQLITE_ABORT].
|
|
*/
|
|
int sqlite3_finalize(sqlite3_stmt *pStmt);
|
|
|
|
/*
|
|
** CAPI3REF: Reset A Prepared Statement Object
|
|
**
|
|
** The sqlite3_reset() function is called to reset a
|
|
** [sqlite3_stmt | compiled SQL statement] object.
|
|
** back to it's initial state, ready to be re-executed.
|
|
** Any SQL statement variables that had values bound to them using
|
|
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
|
|
** Use [sqlite3_clear_bindings()] to reset the bindings.
|
|
*/
|
|
int sqlite3_reset(sqlite3_stmt *pStmt);
|
|
|
|
/*
|
|
** CAPI3REF: Create Or Redefine SQL Functions
|
|
**
|
|
** The following two functions are used to add SQL functions or aggregates
|
|
** or to redefine the behavior of existing SQL functions or aggregates. The
|
|
** difference only between the two is that the second parameter, the
|
|
** name of the (scalar) function or aggregate, is encoded in UTF-8 for
|
|
** sqlite3_create_function() and UTF-16 for sqlite3_create_function16().
|
|
**
|
|
** The first argument is the [sqlite3 | database handle] that holds the
|
|
** SQL function or aggregate is to be added or redefined. If a single
|
|
** program uses more than one database handle internally, then SQL
|
|
** functions or aggregates must be added individually to each database
|
|
** handle with which they will be used.
|
|
**
|
|
** The second parameter is the name of the SQL function to be created
|
|
** or redefined.
|
|
** The length of the name is limited to 255 bytes, exclusive of the
|
|
** zero-terminator. Note that the name length limit is in bytes, not
|
|
** characters. Any attempt to create a function with a longer name
|
|
** will result in an SQLITE_ERROR error.
|
|
**
|
|
** The third parameter is the number of arguments that the SQL function or
|
|
** aggregate takes. If this parameter is negative, then the SQL function or
|
|
** aggregate may take any number of arguments.
|
|
**
|
|
** The fourth parameter, eTextRep, specifies what
|
|
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
|
|
** its parameters. Any SQL function implementation should be able to work
|
|
** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
|
|
** more efficient with one encoding than another. It is allowed to
|
|
** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
|
|
** times with the same function but with different values of eTextRep.
|
|
** When multiple implementations of the same function are available, SQLite
|
|
** will pick the one that involves the least amount of data conversion.
|
|
** If there is only a single implementation which does not care what
|
|
** text encoding is used, then the fourth argument should be
|
|
** [SQLITE_ANY].
|
|
**
|
|
** The fifth parameter is an arbitrary pointer. The implementation
|
|
** of the function can gain access to this pointer using
|
|
** [sqlite3_user_data()].
|
|
**
|
|
** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are
|
|
** pointers to C-language functions that implement the SQL
|
|
** function or aggregate. A scalar SQL function requires an implementation of
|
|
** the xFunc callback only, NULL pointers should be passed as the xStep
|
|
** and xFinal parameters. An aggregate SQL function requires an implementation
|
|
** of xStep and xFinal and NULL should be passed for xFunc. To delete an
|
|
** existing SQL function or aggregate, pass NULL for all three function
|
|
** callback.
|
|
**
|
|
** It is permitted to register multiple implementations of the same
|
|
** functions with the same name but with either differing numbers of
|
|
** arguments or differing perferred text encodings. SQLite will use
|
|
** the implementation most closely matches the way in which the
|
|
** SQL function is used.
|
|
*/
|
|
int sqlite3_create_function(
|
|
sqlite3 *,
|
|
const char *zFunctionName,
|
|
int nArg,
|
|
int eTextRep,
|
|
void*,
|
|
void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
|
|
void (*xStep)(sqlite3_context*,int,sqlite3_value**),
|
|
void (*xFinal)(sqlite3_context*)
|
|
);
|
|
int sqlite3_create_function16(
|
|
sqlite3*,
|
|
const void *zFunctionName,
|
|
int nArg,
|
|
int eTextRep,
|
|
void*,
|
|
void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
|
|
void (*xStep)(sqlite3_context*,int,sqlite3_value**),
|
|
void (*xFinal)(sqlite3_context*)
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Text Encodings
|
|
**
|
|
** These constant define integer codes that represent the various
|
|
** text encodings supported by SQLite.
|
|
*/
|
|
#define SQLITE_UTF8 1
|
|
#define SQLITE_UTF16LE 2
|
|
#define SQLITE_UTF16BE 3
|
|
#define SQLITE_UTF16 4 /* Use native byte order */
|
|
#define SQLITE_ANY 5 /* sqlite3_create_function only */
|
|
#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
|
|
|
|
/*
|
|
** CAPI3REF: Obsolete Functions
|
|
**
|
|
** These functions are all now obsolete. In order to maintain
|
|
** backwards compatibility with older code, we continue to support
|
|
** these functions. However, new development projects should avoid
|
|
** the use of these functions. To help encourage people to avoid
|
|
** using these functions, we are not going to tell you want they do.
|
|
*/
|
|
int sqlite3_aggregate_count(sqlite3_context*);
|
|
int sqlite3_expired(sqlite3_stmt*);
|
|
int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
|
|
int sqlite3_global_recover(void);
|
|
void sqlite3_thread_cleanup(void);
|
|
|
|
/*
|
|
** CAPI3REF: Obtaining SQL Function Parameter Values
|
|
**
|
|
** The C-language implementation of SQL functions and aggregates uses
|
|
** this set of interface routines to access the parameter values on
|
|
** the function or aggregate.
|
|
**
|
|
** The xFunc (for scalar functions) or xStep (for aggregates) parameters
|
|
** to [sqlite3_create_function()] and [sqlite3_create_function16()]
|
|
** define callbacks that implement the SQL functions and aggregates.
|
|
** The 4th parameter to these callbacks is an array of pointers to
|
|
** [sqlite3_value] objects. There is one [sqlite3_value] object for
|
|
** each parameter to the SQL function. These routines are used to
|
|
** extract values from the [sqlite3_value] objects.
|
|
**
|
|
** These routines work just like the corresponding
|
|
** [sqlite3_column_blob | sqlite3_column_* routines] except that
|
|
** these routines take a single [sqlite3_value*] pointer instead
|
|
** of an [sqlite3_stmt*] pointer and an integer column number.
|
|
**
|
|
** The sqlite3_value_text16() interface extracts a UTF16 string
|
|
** in the native byte-order of the host machine. The
|
|
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
|
|
** extract UTF16 strings as big-endian and little-endian respectively.
|
|
**
|
|
** The sqlite3_value_numeric_type() interface attempts to apply
|
|
** numeric affinity to the value. This means that an attempt is
|
|
** made to convert the value to an integer or floating point. If
|
|
** such a conversion is possible without loss of information (in order
|
|
** words if the value is original a string that looks like a number)
|
|
** then it is done. Otherwise no conversion occurs. The
|
|
** [SQLITE_INTEGER | datatype] after conversion is returned.
|
|
**
|
|
** Please pay particular attention to the fact that the pointer that
|
|
** is returned from [sqlite3_value_blob()], [sqlite3_value_text()], or
|
|
** [sqlite3_value_text16()] can be invalidated by a subsequent call to
|
|
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
|
|
** or [sqlite3_value_text16()].
|
|
**
|
|
** These routines must be called from the same thread as
|
|
** the SQL function that supplied the sqlite3_value* parameters.
|
|
** Or, if the sqlite3_value* argument comes from the [sqlite3_column_value()]
|
|
** interface, then these routines should be called from the same thread
|
|
** that ran [sqlite3_column_value()].
|
|
*/
|
|
const void *sqlite3_value_blob(sqlite3_value*);
|
|
int sqlite3_value_bytes(sqlite3_value*);
|
|
int sqlite3_value_bytes16(sqlite3_value*);
|
|
double sqlite3_value_double(sqlite3_value*);
|
|
int sqlite3_value_int(sqlite3_value*);
|
|
sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
|
|
const unsigned char *sqlite3_value_text(sqlite3_value*);
|
|
const void *sqlite3_value_text16(sqlite3_value*);
|
|
const void *sqlite3_value_text16le(sqlite3_value*);
|
|
const void *sqlite3_value_text16be(sqlite3_value*);
|
|
int sqlite3_value_type(sqlite3_value*);
|
|
int sqlite3_value_numeric_type(sqlite3_value*);
|
|
|
|
/*
|
|
** CAPI3REF: Obtain Aggregate Function Context
|
|
**
|
|
** The implementation of aggregate SQL functions use this routine to allocate
|
|
** a structure for storing their state. The first time this routine
|
|
** is called for a particular aggregate, a new structure of size nBytes
|
|
** is allocated, zeroed, and returned. On subsequent calls (for the
|
|
** same aggregate instance) the same buffer is returned. The implementation
|
|
** of the aggregate can use the returned buffer to accumulate data.
|
|
**
|
|
** The buffer allocated is freed automatically by SQLite whan the aggregate
|
|
** query concludes.
|
|
**
|
|
** The first parameter should be a copy of the
|
|
** [sqlite3_context | SQL function context] that is the first
|
|
** parameter to the callback routine that implements the aggregate
|
|
** function.
|
|
**
|
|
** This routine must be called from the same thread in which
|
|
** the aggregate SQL function is running.
|
|
*/
|
|
void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
|
|
|
|
/*
|
|
** CAPI3REF: User Data For Functions
|
|
**
|
|
** The pUserData parameter to the [sqlite3_create_function()]
|
|
** and [sqlite3_create_function16()] routines
|
|
** used to register user functions is available to
|
|
** the implementation of the function using this call.
|
|
**
|
|
** This routine must be called from the same thread in which
|
|
** the SQL function is running.
|
|
*/
|
|
void *sqlite3_user_data(sqlite3_context*);
|
|
|
|
/*
|
|
** CAPI3REF: Function Auxiliary Data
|
|
**
|
|
** The following two functions may be used by scalar SQL functions to
|
|
** associate meta-data with argument values. If the same value is passed to
|
|
** multiple invocations of the same SQL function during query execution, under
|
|
** some circumstances the associated meta-data may be preserved. This may
|
|
** be used, for example, to add a regular-expression matching scalar
|
|
** function. The compiled version of the regular expression is stored as
|
|
** meta-data associated with the SQL value passed as the regular expression
|
|
** pattern. The compiled regular expression can be reused on multiple
|
|
** invocations of the same function so that the original pattern string
|
|
** does not need to be recompiled on each invocation.
|
|
**
|
|
** The sqlite3_get_auxdata() interface returns a pointer to the meta-data
|
|
** associated with the Nth argument value to the current SQL function
|
|
** call, where N is the second parameter. If no meta-data has been set for
|
|
** that value, then a NULL pointer is returned.
|
|
**
|
|
** The sqlite3_set_auxdata() is used to associate meta-data with an SQL
|
|
** function argument. The third parameter is a pointer to the meta-data
|
|
** to be associated with the Nth user function argument value. The fourth
|
|
** parameter specifies a destructor that will be called on the meta-
|
|
** data pointer to release it when it is no longer required. If the
|
|
** destructor is NULL, it is not invoked.
|
|
**
|
|
** In practice, meta-data is preserved between function calls for
|
|
** expressions that are constant at compile time. This includes literal
|
|
** values and SQL variables.
|
|
**
|
|
** These routines must be called from the same thread in which
|
|
** the SQL function is running.
|
|
*/
|
|
void *sqlite3_get_auxdata(sqlite3_context*, int);
|
|
void sqlite3_set_auxdata(sqlite3_context*, int, void*, void (*)(void*));
|
|
|
|
|
|
/*
|
|
** CAPI3REF: Constants Defining Special Destructor Behavior
|
|
**
|
|
** These are special value for the destructor that is passed in as the
|
|
** final argument to routines like [sqlite3_result_blob()]. If the destructor
|
|
** argument is SQLITE_STATIC, it means that the content pointer is constant
|
|
** and will never change. It does not need to be destroyed. The
|
|
** SQLITE_TRANSIENT value means that the content will likely change in
|
|
** the near future and that SQLite should make its own private copy of
|
|
** the content before returning.
|
|
**
|
|
** The typedef is necessary to work around problems in certain
|
|
** C++ compilers. See ticket #2191.
|
|
*/
|
|
typedef void (*sqlite3_destructor_type)(void*);
|
|
#define SQLITE_STATIC ((sqlite3_destructor_type)0)
|
|
#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
|
|
|
|
/*
|
|
** CAPI3REF: Setting The Result Of An SQL Function
|
|
**
|
|
** These routines are used by the xFunc or xFinal callbacks that
|
|
** implement SQL functions and aggregates. See
|
|
** [sqlite3_create_function()] and [sqlite3_create_function16()]
|
|
** for additional information.
|
|
**
|
|
** These functions work very much like the
|
|
** [sqlite3_bind_blob | sqlite3_bind_*] family of functions used
|
|
** to bind values to host parameters in prepared statements.
|
|
** Refer to the
|
|
** [sqlite3_bind_blob | sqlite3_bind_* documentation] for
|
|
** additional information.
|
|
**
|
|
** The sqlite3_result_error() and sqlite3_result_error16() functions
|
|
** cause the implemented SQL function to throw an exception. The
|
|
** parameter to sqlite3_result_error() or sqlite3_result_error16()
|
|
** is the text of an error message.
|
|
**
|
|
** The sqlite3_result_toobig() cause the function implementation
|
|
** to throw and error indicating that a string or BLOB is to long
|
|
** to represent.
|
|
**
|
|
** These routines must be called from within the same thread as
|
|
** the SQL function associated with the [sqlite3_context] pointer.
|
|
*/
|
|
void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
|
|
void sqlite3_result_double(sqlite3_context*, double);
|
|
void sqlite3_result_error(sqlite3_context*, const char*, int);
|
|
void sqlite3_result_error16(sqlite3_context*, const void*, int);
|
|
void sqlite3_result_error_toobig(sqlite3_context*);
|
|
void sqlite3_result_error_nomem(sqlite3_context*);
|
|
void sqlite3_result_int(sqlite3_context*, int);
|
|
void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
|
|
void sqlite3_result_null(sqlite3_context*);
|
|
void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
|
|
void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
|
|
void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
|
|
void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
|
|
void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
|
|
void sqlite3_result_zeroblob(sqlite3_context*, int n);
|
|
|
|
/*
|
|
** CAPI3REF: Define New Collating Sequences
|
|
**
|
|
** These functions are used to add new collation sequences to the
|
|
** [sqlite3*] handle specified as the first argument.
|
|
**
|
|
** The name of the new collation sequence is specified as a UTF-8 string
|
|
** for sqlite3_create_collation() and sqlite3_create_collation_v2()
|
|
** and a UTF-16 string for sqlite3_create_collation16(). In all cases
|
|
** the name is passed as the second function argument.
|
|
**
|
|
** The third argument must be one of the constants [SQLITE_UTF8],
|
|
** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied
|
|
** routine expects to be passed pointers to strings encoded using UTF-8,
|
|
** UTF-16 little-endian or UTF-16 big-endian respectively.
|
|
**
|
|
** A pointer to the user supplied routine must be passed as the fifth
|
|
** argument. If it is NULL, this is the same as deleting the collation
|
|
** sequence (so that SQLite cannot call it anymore). Each time the user
|
|
** supplied function is invoked, it is passed a copy of the void* passed as
|
|
** the fourth argument to sqlite3_create_collation() or
|
|
** sqlite3_create_collation16() as its first parameter.
|
|
**
|
|
** The remaining arguments to the user-supplied routine are two strings,
|
|
** each represented by a [length, data] pair and encoded in the encoding
|
|
** that was passed as the third argument when the collation sequence was
|
|
** registered. The user routine should return negative, zero or positive if
|
|
** the first string is less than, equal to, or greater than the second
|
|
** string. i.e. (STRING1 - STRING2).
|
|
**
|
|
** The sqlite3_create_collation_v2() works like sqlite3_create_collation()
|
|
** excapt that it takes an extra argument which is a destructor for
|
|
** the collation. The destructor is called when the collation is
|
|
** destroyed and is passed a copy of the fourth parameter void* pointer
|
|
** of the sqlite3_create_collation_v2(). Collations are destroyed when
|
|
** they are overridden by later calls to the collation creation functions
|
|
** or when the [sqlite3*] database handle is closed using [sqlite3_close()].
|
|
**
|
|
** The sqlite3_create_collation_v2() interface is experimental and
|
|
** subject to change in future releases. The other collation creation
|
|
** functions are stable.
|
|
*/
|
|
int sqlite3_create_collation(
|
|
sqlite3*,
|
|
const char *zName,
|
|
int eTextRep,
|
|
void*,
|
|
int(*xCompare)(void*,int,const void*,int,const void*)
|
|
);
|
|
int sqlite3_create_collation_v2(
|
|
sqlite3*,
|
|
const char *zName,
|
|
int eTextRep,
|
|
void*,
|
|
int(*xCompare)(void*,int,const void*,int,const void*),
|
|
void(*xDestroy)(void*)
|
|
);
|
|
int sqlite3_create_collation16(
|
|
sqlite3*,
|
|
const char *zName,
|
|
int eTextRep,
|
|
void*,
|
|
int(*xCompare)(void*,int,const void*,int,const void*)
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Collation Needed Callbacks
|
|
**
|
|
** To avoid having to register all collation sequences before a database
|
|
** can be used, a single callback function may be registered with the
|
|
** database handle to be called whenever an undefined collation sequence is
|
|
** required.
|
|
**
|
|
** If the function is registered using the sqlite3_collation_needed() API,
|
|
** then it is passed the names of undefined collation sequences as strings
|
|
** encoded in UTF-8. If sqlite3_collation_needed16() is used, the names
|
|
** are passed as UTF-16 in machine native byte order. A call to either
|
|
** function replaces any existing callback.
|
|
**
|
|
** When the callback is invoked, the first argument passed is a copy
|
|
** of the second argument to sqlite3_collation_needed() or
|
|
** sqlite3_collation_needed16(). The second argument is the database
|
|
** handle. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], or
|
|
** [SQLITE_UTF16LE], indicating the most desirable form of the collation
|
|
** sequence function required. The fourth parameter is the name of the
|
|
** required collation sequence.
|
|
**
|
|
** The callback function should register the desired collation using
|
|
** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
|
|
** [sqlite3_create_collation_v2()].
|
|
*/
|
|
int sqlite3_collation_needed(
|
|
sqlite3*,
|
|
void*,
|
|
void(*)(void*,sqlite3*,int eTextRep,const char*)
|
|
);
|
|
int sqlite3_collation_needed16(
|
|
sqlite3*,
|
|
void*,
|
|
void(*)(void*,sqlite3*,int eTextRep,const void*)
|
|
);
|
|
|
|
/*
|
|
** Specify the key for an encrypted database. This routine should be
|
|
** called right after sqlite3_open().
|
|
**
|
|
** The code to implement this API is not available in the public release
|
|
** of SQLite.
|
|
*/
|
|
int sqlite3_key(
|
|
sqlite3 *db, /* Database to be rekeyed */
|
|
const void *pKey, int nKey /* The key */
|
|
);
|
|
|
|
/*
|
|
** Change the key on an open database. If the current database is not
|
|
** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
|
|
** database is decrypted.
|
|
**
|
|
** The code to implement this API is not available in the public release
|
|
** of SQLite.
|
|
*/
|
|
int sqlite3_rekey(
|
|
sqlite3 *db, /* Database to be rekeyed */
|
|
const void *pKey, int nKey /* The new key */
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Suspend Execution For A Short Time
|
|
**
|
|
** This function causes the current thread to suspend execution
|
|
** a number of milliseconds specified in its parameter.
|
|
**
|
|
** If the operating system does not support sleep requests with
|
|
** millisecond time resolution, then the time will be rounded up to
|
|
** the nearest second. The number of milliseconds of sleep actually
|
|
** requested from the operating system is returned.
|
|
**
|
|
** SQLite implements this interface by calling the xSleep()
|
|
** method of the default [sqlite3_vfs] object.
|
|
*/
|
|
int sqlite3_sleep(int);
|
|
|
|
/*
|
|
** CAPI3REF: Name Of The Folder Holding Temporary Files
|
|
**
|
|
** If this global variable is made to point to a string which is
|
|
** the name of a folder (a.ka. directory), then all temporary files
|
|
** created by SQLite will be placed in that directory. If this variable
|
|
** is NULL pointer, then SQLite does a search for an appropriate temporary
|
|
** file directory.
|
|
**
|
|
** It is not safe to modify this variable once a database connection
|
|
** has been opened. It is intended that this variable be set once
|
|
** as part of process initialization and before any SQLite interface
|
|
** routines have been call and remain unchanged thereafter.
|
|
*/
|
|
SQLITE_EXTERN char *sqlite3_temp_directory;
|
|
|
|
/*
|
|
** CAPI3REF: Test To See If The Database Is In Auto-Commit Mode
|
|
**
|
|
** Test to see whether or not the database connection is in autocommit
|
|
** mode. Return TRUE if it is and FALSE if not. Autocommit mode is on
|
|
** by default. Autocommit is disabled by a BEGIN statement and reenabled
|
|
** by the next COMMIT or ROLLBACK.
|
|
**
|
|
** If certain kinds of errors occur on a statement within a multi-statement
|
|
** transactions (errors including [SQLITE_FULL], [SQLITE_IOERR],
|
|
** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
|
|
** transaction might be rolled back automatically. The only way to
|
|
** find out if SQLite automatically rolled back the transaction after
|
|
** an error is to use this function.
|
|
**
|
|
** If another thread changes the autocommit status of the database
|
|
** connection while this routine is running, then the return value
|
|
** is undefined.
|
|
*/
|
|
int sqlite3_get_autocommit(sqlite3*);
|
|
|
|
/*
|
|
** CAPI3REF: Find The Database Handle Associated With A Prepared Statement
|
|
**
|
|
** Return the [sqlite3*] database handle to which a
|
|
** [sqlite3_stmt | prepared statement] belongs.
|
|
** This is the same database handle that was
|
|
** the first argument to the [sqlite3_prepare_v2()] or its variants
|
|
** that was used to create the statement in the first place.
|
|
*/
|
|
sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
|
|
|
|
|
|
/*
|
|
** CAPI3REF: Commit And Rollback Notification Callbacks
|
|
**
|
|
** These routines
|
|
** register callback functions to be invoked whenever a transaction
|
|
** is committed or rolled back. The pArg argument is passed through
|
|
** to the callback. If the callback on a commit hook function
|
|
** returns non-zero, then the commit is converted into a rollback.
|
|
**
|
|
** If another function was previously registered, its pArg value is returned.
|
|
** Otherwise NULL is returned.
|
|
**
|
|
** Registering a NULL function disables the callback.
|
|
**
|
|
** For the purposes of this API, a transaction is said to have been
|
|
** rolled back if an explicit "ROLLBACK" statement is executed, or
|
|
** an error or constraint causes an implicit rollback to occur. The
|
|
** callback is not invoked if a transaction is automatically rolled
|
|
** back because the database connection is closed.
|
|
**
|
|
** These are experimental interfaces and are subject to change.
|
|
*/
|
|
void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
|
|
void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
|
|
|
|
/*
|
|
** CAPI3REF: Data Change Notification Callbacks
|
|
**
|
|
** Register a callback function with the database connection identified by the
|
|
** first argument to be invoked whenever a row is updated, inserted or deleted.
|
|
** Any callback set by a previous call to this function for the same
|
|
** database connection is overridden.
|
|
**
|
|
** The second argument is a pointer to the function to invoke when a
|
|
** row is updated, inserted or deleted. The first argument to the callback is
|
|
** a copy of the third argument to sqlite3_update_hook(). The second callback
|
|
** argument is one of SQLITE_INSERT, SQLITE_DELETE or SQLITE_UPDATE, depending
|
|
** on the operation that caused the callback to be invoked. The third and
|
|
** fourth arguments to the callback contain pointers to the database and
|
|
** table name containing the affected row. The final callback parameter is
|
|
** the rowid of the row. In the case of an update, this is the rowid after
|
|
** the update takes place.
|
|
**
|
|
** The update hook is not invoked when internal system tables are
|
|
** modified (i.e. sqlite_master and sqlite_sequence).
|
|
**
|
|
** If another function was previously registered, its pArg value is returned.
|
|
** Otherwise NULL is returned.
|
|
*/
|
|
void *sqlite3_update_hook(
|
|
sqlite3*,
|
|
void(*)(void *,int ,char const *,char const *,sqlite3_int64),
|
|
void*
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Enable Or Disable Shared Pager Cache
|
|
**
|
|
** This routine enables or disables the sharing of the database cache
|
|
** and schema data structures between connections to the same database.
|
|
** Sharing is enabled if the argument is true and disabled if the argument
|
|
** is false.
|
|
**
|
|
** Beginning in SQLite version 3.5.0, cache sharing is enabled and disabled
|
|
** for an entire process. In prior versions of SQLite, sharing was
|
|
** enabled or disabled for each thread separately.
|
|
**
|
|
** The cache sharing mode set by this interface effects all subsequent
|
|
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
|
|
** Existing database connections continue use the sharing mode that was
|
|
** in effect at the time they were opened.
|
|
**
|
|
** Virtual tables cannot be used with a shared cache. When shared
|
|
** cache is enabled, the [sqlite3_create_module()] API used to register
|
|
** virtual tables will always return an error.
|
|
**
|
|
** This routine returns [SQLITE_OK] if shared cache was
|
|
** enabled or disabled successfully. An [SQLITE_ERROR | error code]
|
|
** is returned otherwise.
|
|
**
|
|
** Shared cache is disabled by default. But this might change in
|
|
** future releases of SQLite. Applications that care about shared
|
|
** cache setting should set it explicitly.
|
|
*/
|
|
int sqlite3_enable_shared_cache(int);
|
|
|
|
/*
|
|
** CAPI3REF: Attempt To Free Heap Memory
|
|
**
|
|
** Attempt to free N bytes of heap memory by deallocating non-essential
|
|
** memory allocations held by the database library (example: memory
|
|
** used to cache database pages to improve performance).
|
|
*/
|
|
int sqlite3_release_memory(int);
|
|
|
|
/*
|
|
** CAPI3REF: Impose A Limit On Heap Size
|
|
**
|
|
** Place a "soft" limit on the amount of heap memory that may be allocated
|
|
** by SQLite. If an internal allocation is requested
|
|
** that would exceed the specified limit, [sqlite3_release_memory()] is
|
|
** invoked one or more times to free up some space before the allocation
|
|
** is made.
|
|
**
|
|
** The limit is called "soft", because if [sqlite3_release_memory()] cannot
|
|
** free sufficient memory to prevent the limit from being exceeded,
|
|
** the memory is allocated anyway and the current operation proceeds.
|
|
**
|
|
** A negative or zero value for N means that there is no soft heap limit and
|
|
** [sqlite3_release_memory()] will only be called when memory is exhausted.
|
|
** The default value for the soft heap limit is zero.
|
|
**
|
|
** SQLite makes a best effort to honor the soft heap limit. But if it
|
|
** is unable to reduce memory usage below the soft limit, execution will
|
|
** continue without error or notification. This is why the limit is
|
|
** called a "soft" limit. It is advisory only.
|
|
**
|
|
** The soft heap limit is implemented using the [sqlite3_memory_alarm()]
|
|
** interface. Only a single memory alarm is available in the default
|
|
** implementation. This means that if the application also uses the
|
|
** memory alarm interface it will interfere with the operation of the
|
|
** soft heap limit and undefined behavior will result.
|
|
**
|
|
** Prior to SQLite version 3.5.0, this routine only constrained the memory
|
|
** allocated by a single thread - the same thread in which this routine
|
|
** runs. Beginning with SQLite version 3.5.0, the soft heap limit is
|
|
** applied to all threads. The value specified for the soft heap limit
|
|
** is an upper bound on the total memory allocation for all threads. In
|
|
** version 3.5.0 there is no mechanism for limiting the heap usage for
|
|
** individual threads.
|
|
*/
|
|
void sqlite3_soft_heap_limit(int);
|
|
|
|
/*
|
|
** CAPI3REF: Extract Metadata About A Column Of A Table
|
|
**
|
|
** This routine
|
|
** returns meta-data about a specific column of a specific database
|
|
** table accessible using the connection handle passed as the first function
|
|
** argument.
|
|
**
|
|
** The column is identified by the second, third and fourth parameters to
|
|
** this function. The second parameter is either the name of the database
|
|
** (i.e. "main", "temp" or an attached database) containing the specified
|
|
** table or NULL. If it is NULL, then all attached databases are searched
|
|
** for the table using the same algorithm as the database engine uses to
|
|
** resolve unqualified table references.
|
|
**
|
|
** The third and fourth parameters to this function are the table and column
|
|
** name of the desired column, respectively. Neither of these parameters
|
|
** may be NULL.
|
|
**
|
|
** Meta information is returned by writing to the memory locations passed as
|
|
** the 5th and subsequent parameters to this function. Any of these
|
|
** arguments may be NULL, in which case the corresponding element of meta
|
|
** information is ommitted.
|
|
**
|
|
** <pre>
|
|
** Parameter Output Type Description
|
|
** -----------------------------------
|
|
**
|
|
** 5th const char* Data type
|
|
** 6th const char* Name of the default collation sequence
|
|
** 7th int True if the column has a NOT NULL constraint
|
|
** 8th int True if the column is part of the PRIMARY KEY
|
|
** 9th int True if the column is AUTOINCREMENT
|
|
** </pre>
|
|
**
|
|
**
|
|
** The memory pointed to by the character pointers returned for the
|
|
** declaration type and collation sequence is valid only until the next
|
|
** call to any sqlite API function.
|
|
**
|
|
** If the specified table is actually a view, then an error is returned.
|
|
**
|
|
** If the specified column is "rowid", "oid" or "_rowid_" and an
|
|
** INTEGER PRIMARY KEY column has been explicitly declared, then the output
|
|
** parameters are set for the explicitly declared column. If there is no
|
|
** explicitly declared IPK column, then the output parameters are set as
|
|
** follows:
|
|
**
|
|
** <pre>
|
|
** data type: "INTEGER"
|
|
** collation sequence: "BINARY"
|
|
** not null: 0
|
|
** primary key: 1
|
|
** auto increment: 0
|
|
** </pre>
|
|
**
|
|
** This function may load one or more schemas from database files. If an
|
|
** error occurs during this process, or if the requested table or column
|
|
** cannot be found, an SQLITE error code is returned and an error message
|
|
** left in the database handle (to be retrieved using sqlite3_errmsg()).
|
|
**
|
|
** This API is only available if the library was compiled with the
|
|
** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined.
|
|
*/
|
|
int sqlite3_table_column_metadata(
|
|
sqlite3 *db, /* Connection handle */
|
|
const char *zDbName, /* Database name or NULL */
|
|
const char *zTableName, /* Table name */
|
|
const char *zColumnName, /* Column name */
|
|
char const **pzDataType, /* OUTPUT: Declared data type */
|
|
char const **pzCollSeq, /* OUTPUT: Collation sequence name */
|
|
int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
|
|
int *pPrimaryKey, /* OUTPUT: True if column part of PK */
|
|
int *pAutoinc /* OUTPUT: True if column is auto-increment */
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Load An Extension
|
|
**
|
|
** Attempt to load an SQLite extension library contained in the file
|
|
** zFile. The entry point is zProc. zProc may be 0 in which case the
|
|
** name of the entry point defaults to "sqlite3_extension_init".
|
|
**
|
|
** Return [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
|
|
**
|
|
** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with
|
|
** error message text. The calling function should free this memory
|
|
** by calling [sqlite3_free()].
|
|
**
|
|
** Extension loading must be enabled using [sqlite3_enable_load_extension()]
|
|
** prior to calling this API or an error will be returned.
|
|
*/
|
|
int sqlite3_load_extension(
|
|
sqlite3 *db, /* Load the extension into this database connection */
|
|
const char *zFile, /* Name of the shared library containing extension */
|
|
const char *zProc, /* Entry point. Derived from zFile if 0 */
|
|
char **pzErrMsg /* Put error message here if not 0 */
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Enable Or Disable Extension Loading
|
|
**
|
|
** So as not to open security holes in older applications that are
|
|
** unprepared to deal with extension loading, and as a means of disabling
|
|
** extension loading while evaluating user-entered SQL, the following
|
|
** API is provided to turn the [sqlite3_load_extension()] mechanism on and
|
|
** off. It is off by default. See ticket #1863.
|
|
**
|
|
** Call this routine with onoff==1 to turn extension loading on
|
|
** and call it with onoff==0 to turn it back off again.
|
|
*/
|
|
int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
|
|
|
|
/*
|
|
** CAPI3REF: Make Arrangements To Automatically Load An Extension
|
|
**
|
|
** Register an extension entry point that is automatically invoked
|
|
** whenever a new database connection is opened using
|
|
** [sqlite3_open()], [sqlite3_open16()], or [sqlite3_open_v2()].
|
|
**
|
|
** This API can be invoked at program startup in order to register
|
|
** one or more statically linked extensions that will be available
|
|
** to all new database connections.
|
|
**
|
|
** Duplicate extensions are detected so calling this routine multiple
|
|
** times with the same extension is harmless.
|
|
**
|
|
** This routine stores a pointer to the extension in an array
|
|
** that is obtained from malloc(). If you run a memory leak
|
|
** checker on your program and it reports a leak because of this
|
|
** array, then invoke [sqlite3_automatic_extension_reset()] prior
|
|
** to shutdown to free the memory.
|
|
**
|
|
** Automatic extensions apply across all threads.
|
|
**
|
|
** This interface is experimental and is subject to change or
|
|
** removal in future releases of SQLite.
|
|
*/
|
|
int sqlite3_auto_extension(void *xEntryPoint);
|
|
|
|
|
|
/*
|
|
** CAPI3REF: Reset Automatic Extension Loading
|
|
**
|
|
** Disable all previously registered automatic extensions. This
|
|
** routine undoes the effect of all prior [sqlite3_automatic_extension()]
|
|
** calls.
|
|
**
|
|
** This call disabled automatic extensions in all threads.
|
|
**
|
|
** This interface is experimental and is subject to change or
|
|
** removal in future releases of SQLite.
|
|
*/
|
|
void sqlite3_reset_auto_extension(void);
|
|
|
|
|
|
/*
|
|
****** EXPERIMENTAL - subject to change without notice **************
|
|
**
|
|
** The interface to the virtual-table mechanism is currently considered
|
|
** to be experimental. The interface might change in incompatible ways.
|
|
** If this is a problem for you, do not use the interface at this time.
|
|
**
|
|
** When the virtual-table mechanism stablizes, we will declare the
|
|
** interface fixed, support it indefinitely, and remove this comment.
|
|
*/
|
|
|
|
/*
|
|
** Structures used by the virtual table interface
|
|
*/
|
|
typedef struct sqlite3_vtab sqlite3_vtab;
|
|
typedef struct sqlite3_index_info sqlite3_index_info;
|
|
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
|
|
typedef struct sqlite3_module sqlite3_module;
|
|
|
|
/*
|
|
** A module is a class of virtual tables. Each module is defined
|
|
** by an instance of the following structure. This structure consists
|
|
** mostly of methods for the module.
|
|
*/
|
|
struct sqlite3_module {
|
|
int iVersion;
|
|
int (*xCreate)(sqlite3*, void *pAux,
|
|
int argc, const char *const*argv,
|
|
sqlite3_vtab **ppVTab, char**);
|
|
int (*xConnect)(sqlite3*, void *pAux,
|
|
int argc, const char *const*argv,
|
|
sqlite3_vtab **ppVTab, char**);
|
|
int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
|
|
int (*xDisconnect)(sqlite3_vtab *pVTab);
|
|
int (*xDestroy)(sqlite3_vtab *pVTab);
|
|
int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
|
|
int (*xClose)(sqlite3_vtab_cursor*);
|
|
int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
|
|
int argc, sqlite3_value **argv);
|
|
int (*xNext)(sqlite3_vtab_cursor*);
|
|
int (*xEof)(sqlite3_vtab_cursor*);
|
|
int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
|
|
int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
|
|
int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
|
|
int (*xBegin)(sqlite3_vtab *pVTab);
|
|
int (*xSync)(sqlite3_vtab *pVTab);
|
|
int (*xCommit)(sqlite3_vtab *pVTab);
|
|
int (*xRollback)(sqlite3_vtab *pVTab);
|
|
int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
|
|
void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
|
|
void **ppArg);
|
|
|
|
int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
|
|
};
|
|
|
|
/*
|
|
** The sqlite3_index_info structure and its substructures is used to
|
|
** pass information into and receive the reply from the xBestIndex
|
|
** method of an sqlite3_module. The fields under **Inputs** are the
|
|
** inputs to xBestIndex and are read-only. xBestIndex inserts its
|
|
** results into the **Outputs** fields.
|
|
**
|
|
** The aConstraint[] array records WHERE clause constraints of the
|
|
** form:
|
|
**
|
|
** column OP expr
|
|
**
|
|
** Where OP is =, <, <=, >, or >=. The particular operator is stored
|
|
** in aConstraint[].op. The index of the column is stored in
|
|
** aConstraint[].iColumn. aConstraint[].usable is TRUE if the
|
|
** expr on the right-hand side can be evaluated (and thus the constraint
|
|
** is usable) and false if it cannot.
|
|
**
|
|
** The optimizer automatically inverts terms of the form "expr OP column"
|
|
** and makes other simplifications to the WHERE clause in an attempt to
|
|
** get as many WHERE clause terms into the form shown above as possible.
|
|
** The aConstraint[] array only reports WHERE clause terms in the correct
|
|
** form that refer to the particular virtual table being queried.
|
|
**
|
|
** Information about the ORDER BY clause is stored in aOrderBy[].
|
|
** Each term of aOrderBy records a column of the ORDER BY clause.
|
|
**
|
|
** The xBestIndex method must fill aConstraintUsage[] with information
|
|
** about what parameters to pass to xFilter. If argvIndex>0 then
|
|
** the right-hand side of the corresponding aConstraint[] is evaluated
|
|
** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit
|
|
** is true, then the constraint is assumed to be fully handled by the
|
|
** virtual table and is not checked again by SQLite.
|
|
**
|
|
** The idxNum and idxPtr values are recorded and passed into xFilter.
|
|
** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
|
|
**
|
|
** The orderByConsumed means that output from xFilter will occur in
|
|
** the correct order to satisfy the ORDER BY clause so that no separate
|
|
** sorting step is required.
|
|
**
|
|
** The estimatedCost value is an estimate of the cost of doing the
|
|
** particular lookup. A full scan of a table with N entries should have
|
|
** a cost of N. A binary search of a table of N entries should have a
|
|
** cost of approximately log(N).
|
|
*/
|
|
struct sqlite3_index_info {
|
|
/* Inputs */
|
|
int nConstraint; /* Number of entries in aConstraint */
|
|
struct sqlite3_index_constraint {
|
|
int iColumn; /* Column on left-hand side of constraint */
|
|
unsigned char op; /* Constraint operator */
|
|
unsigned char usable; /* True if this constraint is usable */
|
|
int iTermOffset; /* Used internally - xBestIndex should ignore */
|
|
} *aConstraint; /* Table of WHERE clause constraints */
|
|
int nOrderBy; /* Number of terms in the ORDER BY clause */
|
|
struct sqlite3_index_orderby {
|
|
int iColumn; /* Column number */
|
|
unsigned char desc; /* True for DESC. False for ASC. */
|
|
} *aOrderBy; /* The ORDER BY clause */
|
|
|
|
/* Outputs */
|
|
struct sqlite3_index_constraint_usage {
|
|
int argvIndex; /* if >0, constraint is part of argv to xFilter */
|
|
unsigned char omit; /* Do not code a test for this constraint */
|
|
} *aConstraintUsage;
|
|
int idxNum; /* Number used to identify the index */
|
|
char *idxStr; /* String, possibly obtained from sqlite3_malloc */
|
|
int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
|
|
int orderByConsumed; /* True if output is already ordered */
|
|
double estimatedCost; /* Estimated cost of using this index */
|
|
};
|
|
#define SQLITE_INDEX_CONSTRAINT_EQ 2
|
|
#define SQLITE_INDEX_CONSTRAINT_GT 4
|
|
#define SQLITE_INDEX_CONSTRAINT_LE 8
|
|
#define SQLITE_INDEX_CONSTRAINT_LT 16
|
|
#define SQLITE_INDEX_CONSTRAINT_GE 32
|
|
#define SQLITE_INDEX_CONSTRAINT_MATCH 64
|
|
|
|
/*
|
|
** This routine is used to register a new module name with an SQLite
|
|
** connection. Module names must be registered before creating new
|
|
** virtual tables on the module, or before using preexisting virtual
|
|
** tables of the module.
|
|
*/
|
|
int sqlite3_create_module(
|
|
sqlite3 *db, /* SQLite connection to register module with */
|
|
const char *zName, /* Name of the module */
|
|
const sqlite3_module *, /* Methods for the module */
|
|
void * /* Client data for xCreate/xConnect */
|
|
);
|
|
|
|
/*
|
|
** This routine is identical to the sqlite3_create_module() method above,
|
|
** except that it allows a destructor function to be specified. It is
|
|
** even more experimental than the rest of the virtual tables API.
|
|
*/
|
|
int sqlite3_create_module_v2(
|
|
sqlite3 *db, /* SQLite connection to register module with */
|
|
const char *zName, /* Name of the module */
|
|
const sqlite3_module *, /* Methods for the module */
|
|
void *, /* Client data for xCreate/xConnect */
|
|
void(*xDestroy)(void*) /* Module destructor function */
|
|
);
|
|
|
|
/*
|
|
** Every module implementation uses a subclass of the following structure
|
|
** to describe a particular instance of the module. Each subclass will
|
|
** be tailored to the specific needs of the module implementation. The
|
|
** purpose of this superclass is to define certain fields that are common
|
|
** to all module implementations.
|
|
**
|
|
** Virtual tables methods can set an error message by assigning a
|
|
** string obtained from sqlite3_mprintf() to zErrMsg. The method should
|
|
** take care that any prior string is freed by a call to sqlite3_free()
|
|
** prior to assigning a new string to zErrMsg. After the error message
|
|
** is delivered up to the client application, the string will be automatically
|
|
** freed by sqlite3_free() and the zErrMsg field will be zeroed. Note
|
|
** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
|
|
** since virtual tables are commonly implemented in loadable extensions which
|
|
** do not have access to sqlite3MPrintf() or sqlite3Free().
|
|
*/
|
|
struct sqlite3_vtab {
|
|
const sqlite3_module *pModule; /* The module for this virtual table */
|
|
int nRef; /* Used internally */
|
|
char *zErrMsg; /* Error message from sqlite3_mprintf() */
|
|
/* Virtual table implementations will typically add additional fields */
|
|
};
|
|
|
|
/* Every module implementation uses a subclass of the following structure
|
|
** to describe cursors that point into the virtual table and are used
|
|
** to loop through the virtual table. Cursors are created using the
|
|
** xOpen method of the module. Each module implementation will define
|
|
** the content of a cursor structure to suit its own needs.
|
|
**
|
|
** This superclass exists in order to define fields of the cursor that
|
|
** are common to all implementations.
|
|
*/
|
|
struct sqlite3_vtab_cursor {
|
|
sqlite3_vtab *pVtab; /* Virtual table of this cursor */
|
|
/* Virtual table implementations will typically add additional fields */
|
|
};
|
|
|
|
/*
|
|
** The xCreate and xConnect methods of a module use the following API
|
|
** to declare the format (the names and datatypes of the columns) of
|
|
** the virtual tables they implement.
|
|
*/
|
|
int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
|
|
|
|
/*
|
|
** Virtual tables can provide alternative implementations of functions
|
|
** using the xFindFunction method. But global versions of those functions
|
|
** must exist in order to be overloaded.
|
|
**
|
|
** This API makes sure a global version of a function with a particular
|
|
** name and number of parameters exists. If no such function exists
|
|
** before this API is called, a new function is created. The implementation
|
|
** of the new function always causes an exception to be thrown. So
|
|
** the new function is not good for anything by itself. Its only
|
|
** purpose is to be a place-holder function that can be overloaded
|
|
** by virtual tables.
|
|
**
|
|
** This API should be considered part of the virtual table interface,
|
|
** which is experimental and subject to change.
|
|
*/
|
|
int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
|
|
|
|
/*
|
|
** The interface to the virtual-table mechanism defined above (back up
|
|
** to a comment remarkably similar to this one) is currently considered
|
|
** to be experimental. The interface might change in incompatible ways.
|
|
** If this is a problem for you, do not use the interface at this time.
|
|
**
|
|
** When the virtual-table mechanism stabilizes, we will declare the
|
|
** interface fixed, support it indefinitely, and remove this comment.
|
|
**
|
|
****** EXPERIMENTAL - subject to change without notice **************
|
|
*/
|
|
|
|
/*
|
|
** CAPI3REF: A Handle To An Open BLOB
|
|
**
|
|
** An instance of the following opaque structure is used to
|
|
** represent an blob-handle. A blob-handle is created by
|
|
** [sqlite3_blob_open()] and destroyed by [sqlite3_blob_close()].
|
|
** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
|
|
** can be used to read or write small subsections of the blob.
|
|
** The [sqlite3_blob_bytes()] interface returns the size of the
|
|
** blob in bytes.
|
|
*/
|
|
typedef struct sqlite3_blob sqlite3_blob;
|
|
|
|
/*
|
|
** CAPI3REF: Open A BLOB For Incremental I/O
|
|
**
|
|
** Open a handle to the blob located in row iRow,, column zColumn,
|
|
** table zTable in database zDb. i.e. the same blob that would
|
|
** be selected by:
|
|
**
|
|
** <pre>
|
|
** SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
|
|
** </pre>
|
|
**
|
|
** If the flags parameter is non-zero, the blob is opened for
|
|
** read and write access. If it is zero, the blob is opened for read
|
|
** access.
|
|
**
|
|
** On success, [SQLITE_OK] is returned and the new
|
|
** [sqlite3_blob | blob handle] is written to *ppBlob.
|
|
** Otherwise an error code is returned and
|
|
** any value written to *ppBlob should not be used by the caller.
|
|
** This function sets the database-handle error code and message
|
|
** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()].
|
|
*/
|
|
int sqlite3_blob_open(
|
|
sqlite3*,
|
|
const char *zDb,
|
|
const char *zTable,
|
|
const char *zColumn,
|
|
sqlite3_int64 iRow,
|
|
int flags,
|
|
sqlite3_blob **ppBlob
|
|
);
|
|
|
|
/*
|
|
** CAPI3REF: Close A BLOB Handle
|
|
**
|
|
** Close an open [sqlite3_blob | blob handle].
|
|
*/
|
|
int sqlite3_blob_close(sqlite3_blob *);
|
|
|
|
/*
|
|
** CAPI3REF: Return The Size Of An Open BLOB
|
|
**
|
|
** Return the size in bytes of the blob accessible via the open
|
|
** [sqlite3_blob | blob-handle] passed as an argument.
|
|
*/
|
|
int sqlite3_blob_bytes(sqlite3_blob *);
|
|
|
|
/*
|
|
** CAPI3REF: Read Data From A BLOB Incrementally
|
|
**
|
|
** This function is used to read data from an open
|
|
** [sqlite3_blob | blob-handle] into a caller supplied buffer.
|
|
** n bytes of data are copied into buffer
|
|
** z from the open blob, starting at offset iOffset.
|
|
**
|
|
** On success, SQLITE_OK is returned. Otherwise, an
|
|
** [SQLITE_ERROR | SQLite error code] or an
|
|
** [SQLITE_IOERR_READ | extended error code] is returned.
|
|
*/
|
|
int sqlite3_blob_read(sqlite3_blob *, void *z, int n, int iOffset);
|
|
|
|
/*
|
|
** CAPI3REF: Write Data Into A BLOB Incrementally
|
|
**
|
|
** This function is used to write data into an open
|
|
** [sqlite3_blob | blob-handle] from a user supplied buffer.
|
|
** n bytes of data are copied from the buffer
|
|
** pointed to by z into the open blob, starting at offset iOffset.
|
|
**
|
|
** If the [sqlite3_blob | blob-handle] passed as the first argument
|
|
** was not opened for writing (the flags parameter to [sqlite3_blob_open()]
|
|
*** was zero), this function returns [SQLITE_READONLY].
|
|
**
|
|
** This function may only modify the contents of the blob, it is
|
|
** not possible to increase the size of a blob using this API. If
|
|
** offset iOffset is less than n bytes from the end of the blob,
|
|
** [SQLITE_ERROR] is returned and no data is written.
|
|
**
|
|
** On success, SQLITE_OK is returned. Otherwise, an
|
|
** [SQLITE_ERROR | SQLite error code] or an
|
|
** [SQLITE_IOERR_READ | extended error code] is returned.
|
|
*/
|
|
int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
|
|
|
|
/*
|
|
** CAPI3REF: Virtual File System Objects
|
|
**
|
|
** A virtual filesystem (VFS) is an [sqlite3_vfs] object
|
|
** that SQLite uses to interact
|
|
** with the underlying operating system. Most builds come with a
|
|
** single default VFS that is appropriate for the host computer.
|
|
** New VFSes can be registered and existing VFSes can be unregistered.
|
|
** The following interfaces are provided.
|
|
**
|
|
** The sqlite3_vfs_find() interface returns a pointer to a VFS given its
|
|
** name. Names are case sensitive. If there is no match, a NULL
|
|
** pointer is returned. If zVfsName is NULL then the default
|
|
** VFS is returned.
|
|
**
|
|
** New VFSes are registered with sqlite3_vfs_register(). Each
|
|
** new VFS becomes the default VFS if the makeDflt flag is set.
|
|
** The same VFS can be registered multiple times without injury.
|
|
** To make an existing VFS into the default VFS, register it again
|
|
** with the makeDflt flag set. If two different VFSes with the
|
|
** same name are registered, the behavior is undefined. If a
|
|
** VFS is registered with a name that is NULL or an empty string,
|
|
** then the behavior is undefined.
|
|
**
|
|
** Unregister a VFS with the sqlite3_vfs_unregister() interface.
|
|
** If the default VFS is unregistered, another VFS is chosen as
|
|
** the default. The choice for the new VFS is arbitrary.
|
|
*/
|
|
sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
|
|
int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
|
|
int sqlite3_vfs_unregister(sqlite3_vfs*);
|
|
|
|
/*
|
|
** CAPI3REF: Mutexes
|
|
**
|
|
** The SQLite core uses these routines for thread
|
|
** synchronization. Though they are intended for internal
|
|
** use by SQLite, code that links against SQLite is
|
|
** permitted to use any of these routines.
|
|
**
|
|
** The SQLite source code contains multiple implementations
|
|
** of these mutex routines. An appropriate implementation
|
|
** is selected automatically at compile-time. The following
|
|
** implementations are available in the SQLite core:
|
|
**
|
|
** <ul>
|
|
** <li> SQLITE_MUTEX_OS2
|
|
** <li> SQLITE_MUTEX_PTHREAD
|
|
** <li> SQLITE_MUTEX_W32
|
|
** <li> SQLITE_MUTEX_NOOP
|
|
** </ul>
|
|
**
|
|
** The SQLITE_MUTEX_NOOP implementation is a set of routines
|
|
** that does no real locking and is appropriate for use in
|
|
** a single-threaded application. The SQLITE_MUTEX_OS2,
|
|
** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations
|
|
** are appropriate for use on os/2, unix, and windows.
|
|
**
|
|
** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
|
|
** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
|
|
** implementation is included with the library. The
|
|
** mutex interface routines defined here become external
|
|
** references in the SQLite library for which implementations
|
|
** must be provided by the application. This facility allows an
|
|
** application that links against SQLite to provide its own mutex
|
|
** implementation without having to modify the SQLite core.
|
|
**
|
|
** The sqlite3_mutex_alloc() routine allocates a new
|
|
** mutex and returns a pointer to it. If it returns NULL
|
|
** that means that a mutex could not be allocated. SQLite
|
|
** will unwind its stack and return an error. The argument
|
|
** to sqlite3_mutex_alloc() is one of these integer constants:
|
|
**
|
|
** <ul>
|
|
** <li> SQLITE_MUTEX_FAST
|
|
** <li> SQLITE_MUTEX_RECURSIVE
|
|
** <li> SQLITE_MUTEX_STATIC_MASTER
|
|
** <li> SQLITE_MUTEX_STATIC_MEM
|
|
** <li> SQLITE_MUTEX_STATIC_MEM2
|
|
** <li> SQLITE_MUTEX_STATIC_PRNG
|
|
** <li> SQLITE_MUTEX_STATIC_LRU
|
|
** </ul>
|
|
**
|
|
** The first two constants cause sqlite3_mutex_alloc() to create
|
|
** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
|
|
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
|
|
** The mutex implementation does not need to make a distinction
|
|
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
|
|
** not want to. But SQLite will only request a recursive mutex in
|
|
** cases where it really needs one. If a faster non-recursive mutex
|
|
** implementation is available on the host platform, the mutex subsystem
|
|
** might return such a mutex in response to SQLITE_MUTEX_FAST.
|
|
**
|
|
** The other allowed parameters to sqlite3_mutex_alloc() each return
|
|
** a pointer to a static preexisting mutex. Four static mutexes are
|
|
** used by the current version of SQLite. Future versions of SQLite
|
|
** may add additional static mutexes. Static mutexes are for internal
|
|
** use by SQLite only. Applications that use SQLite mutexes should
|
|
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
|
|
** SQLITE_MUTEX_RECURSIVE.
|
|
**
|
|
** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
|
|
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
|
|
** returns a different mutex on every call. But for the static
|
|
** mutex types, the same mutex is returned on every call that has
|
|
** the same type number.
|
|
**
|
|
** The sqlite3_mutex_free() routine deallocates a previously
|
|
** allocated dynamic mutex. SQLite is careful to deallocate every
|
|
** dynamic mutex that it allocates. The dynamic mutexes must not be in
|
|
** use when they are deallocated. Attempting to deallocate a static
|
|
** mutex results in undefined behavior. SQLite never deallocates
|
|
** a static mutex.
|
|
**
|
|
** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
|
|
** to enter a mutex. If another thread is already within the mutex,
|
|
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
|
|
** SQLITE_BUSY. The sqlite3_mutex_try() interface returns SQLITE_OK
|
|
** upon successful entry. Mutexes created using SQLITE_MUTEX_RECURSIVE can
|
|
** be entered multiple times by the same thread. In such cases the,
|
|
** mutex must be exited an equal number of times before another thread
|
|
** can enter. If the same thread tries to enter any other kind of mutex
|
|
** more than once, the behavior is undefined. SQLite will never exhibit
|
|
** such behavior in its own use of mutexes.
|
|
**
|
|
** Some systems (ex: windows95) do not the operation implemented by
|
|
** sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() will
|
|
** always return SQLITE_BUSY. The SQLite core only ever uses
|
|
** sqlite3_mutex_try() as an optimization so this is acceptable behavior.
|
|
**
|
|
** The sqlite3_mutex_leave() routine exits a mutex that was
|
|
** previously entered by the same thread. The behavior
|
|
** is undefined if the mutex is not currently entered by the
|
|
** calling thread or is not currently allocated. SQLite will
|
|
** never do either.
|
|
**
|
|
** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
|
|
*/
|
|
sqlite3_mutex *sqlite3_mutex_alloc(int);
|
|
void sqlite3_mutex_free(sqlite3_mutex*);
|
|
void sqlite3_mutex_enter(sqlite3_mutex*);
|
|
int sqlite3_mutex_try(sqlite3_mutex*);
|
|
void sqlite3_mutex_leave(sqlite3_mutex*);
|
|
|
|
/*
|
|
** CAPI3REF: Mutex Verifcation Routines
|
|
**
|
|
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
|
|
** are intended for use inside assert() statements. The SQLite core
|
|
** never uses these routines except inside an assert() and applications
|
|
** are advised to follow the lead of the core. The core only
|
|
** provides implementations for these routines when it is compiled
|
|
** with the SQLITE_DEBUG flag. External mutex implementations
|
|
** are only required to provide these routines if SQLITE_DEBUG is
|
|
** defined and if NDEBUG is not defined.
|
|
**
|
|
** These routines should return true if the mutex in their argument
|
|
** is held or not held, respectively, by the calling thread.
|
|
**
|
|
** The implementation is not required to provided versions of these
|
|
** routines that actually work.
|
|
** If the implementation does not provide working
|
|
** versions of these routines, it should at least provide stubs
|
|
** that always return true so that one does not get spurious
|
|
** assertion failures.
|
|
**
|
|
** If the argument to sqlite3_mutex_held() is a NULL pointer then
|
|
** the routine should return 1. This seems counter-intuitive since
|
|
** clearly the mutex cannot be held if it does not exist. But the
|
|
** the reason the mutex does not exist is because the build is not
|
|
** using mutexes. And we do not want the assert() containing the
|
|
** call to sqlite3_mutex_held() to fail, so a non-zero return is
|
|
** the appropriate thing to do. The sqlite3_mutex_notheld()
|
|
** interface should also return 1 when given a NULL pointer.
|
|
*/
|
|
int sqlite3_mutex_held(sqlite3_mutex*);
|
|
int sqlite3_mutex_notheld(sqlite3_mutex*);
|
|
|
|
/*
|
|
** CAPI3REF: Mutex Types
|
|
**
|
|
** The [sqlite3_mutex_alloc()] interface takes a single argument
|
|
** which is one of these integer constants.
|
|
*/
|
|
#define SQLITE_MUTEX_FAST 0
|
|
#define SQLITE_MUTEX_RECURSIVE 1
|
|
#define SQLITE_MUTEX_STATIC_MASTER 2
|
|
#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
|
|
#define SQLITE_MUTEX_STATIC_MEM2 4 /* sqlite3_release_memory() */
|
|
#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
|
|
#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
|
|
|
|
/*
|
|
** CAPI3REF: Low-Level Control Of Database Files
|
|
**
|
|
** The [sqlite3_file_control()] interface makes a direct call to the
|
|
** xFileControl method for the [sqlite3_io_methods] object associated
|
|
** with a particular database identified by the second argument. The
|
|
** name of the database is the name assigned to the database by the
|
|
** <a href="lang_attach.html">ATTACH</a> SQL command that opened the
|
|
** database. To control the main database file, use the name "main"
|
|
** or a NULL pointer. The third and fourth parameters to this routine
|
|
** are passed directly through to the second and third parameters of
|
|
** the xFileControl method. The return value of the xFileControl
|
|
** method becomes the return value of this routine.
|
|
**
|
|
** If the second parameter (zDbName) does not match the name of any
|
|
** open database file, then SQLITE_ERROR is returned. This error
|
|
** code is not remembered and will not be recalled by [sqlite3_errcode()]
|
|
** or [sqlite3_errmsg()]. The underlying xFileControl method might
|
|
** also return SQLITE_ERROR. There is no way to distinguish between
|
|
** an incorrect zDbName and an SQLITE_ERROR return from the underlying
|
|
** xFileControl method.
|
|
**
|
|
** See also: [SQLITE_FCNTL_LOCKSTATE]
|
|
*/
|
|
int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
|
|
|
|
/*
|
|
** Undo the hack that converts floating point types to integer for
|
|
** builds on processors without floating point support.
|
|
*/
|
|
#ifdef SQLITE_OMIT_FLOATING_POINT
|
|
# undef double
|
|
#endif
|
|
|
|
#ifdef __cplusplus
|
|
} /* End of the 'extern "C"' block */
|
|
#endif
|
|
#endif
|