rt-thread/components/external/SQLite-3.8.1/SQLiteLib/test/test_intarray.h

129 lines
4.5 KiB
C

/*
** 2009 November 10
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
**
** This is the C-language interface definition for the "intarray" or
** integer array virtual table for SQLite.
**
** The intarray virtual table is designed to facilitate using an
** array of integers as the right-hand side of an IN operator. So
** instead of doing a prepared statement like this:
**
** SELECT * FROM table WHERE x IN (?,?,?,...,?);
**
** And then binding indivdual integers to each of ? slots, a C-language
** application can create an intarray object (named "ex1" in the following
** example), prepare a statement like this:
**
** SELECT * FROM table WHERE x IN ex1;
**
** Then bind an ordinary C/C++ array of integer values to the ex1 object
** to run the statement.
**
** USAGE:
**
** One or more intarray objects can be created as follows:
**
** sqlite3_intarray *p1, *p2, *p3;
** sqlite3_intarray_create(db, "ex1", &p1);
** sqlite3_intarray_create(db, "ex2", &p2);
** sqlite3_intarray_create(db, "ex3", &p3);
**
** Each call to sqlite3_intarray_create() generates a new virtual table
** module and a singleton of that virtual table module in the TEMP
** database. Both the module and the virtual table instance use the
** name given by the second parameter. The virtual tables can then be
** used in prepared statements:
**
** SELECT * FROM t1, t2, t3
** WHERE t1.x IN ex1
** AND t2.y IN ex2
** AND t3.z IN ex3;
**
** Each integer array is initially empty. New arrays can be bound to
** an integer array as follows:
**
** sqlite3_int64 a1[] = { 1, 2, 3, 4 };
** sqlite3_int64 a2[] = { 5, 6, 7, 8, 9, 10, 11 };
** sqlite3_int64 *a3 = sqlite3_malloc( 100*sizeof(sqlite3_int64) );
** // Fill in content of a3[]
** sqlite3_intarray_bind(p1, 4, a1, 0);
** sqlite3_intarray_bind(p2, 7, a2, 0);
** sqlite3_intarray_bind(p3, 100, a3, sqlite3_free);
**
** A single intarray object can be rebound multiple times. But do not
** attempt to change the bindings of an intarray while it is in the middle
** of a query.
**
** The array that holds the integers is automatically freed by the function
** in the fourth parameter to sqlite3_intarray_bind() when the array is no
** longer needed. The application must not change the intarray values
** while an intarray is in the middle of a query.
**
** The intarray object is automatically destroyed when its corresponding
** virtual table is dropped. Since the virtual tables are created in the
** TEMP database, they are automatically dropped when the database connection
** closes so the application does not normally need to take any special
** action to free the intarray objects.
*/
#include "sqlite3.h"
#ifndef _INTARRAY_H_
#define _INTARRAY_H_
/*
** Make sure we can call this stuff from C++.
*/
#ifdef __cplusplus
extern "C" {
#endif
/*
** An sqlite3_intarray is an abstract type to stores an instance of
** an integer array.
*/
typedef struct sqlite3_intarray sqlite3_intarray;
/*
** Invoke this routine to create a specific instance of an intarray object.
** The new intarray object is returned by the 3rd parameter.
**
** Each intarray object corresponds to a virtual table in the TEMP table
** with a name of zName.
**
** Destroy the intarray object by dropping the virtual table. If not done
** explicitly by the application, the virtual table will be dropped implicitly
** by the system when the database connection is closed.
*/
int sqlite3_intarray_create(
sqlite3 *db,
const char *zName,
sqlite3_intarray **ppReturn
);
/*
** Bind a new array array of integers to a specific intarray object.
**
** The array of integers bound must be unchanged for the duration of
** any query against the corresponding virtual table. If the integer
** array does change or is deallocated undefined behavior will result.
*/
int sqlite3_intarray_bind(
sqlite3_intarray *pIntArray, /* The intarray object to bind to */
int nElements, /* Number of elements in the intarray */
sqlite3_int64 *aElements, /* Content of the intarray */
void (*xFree)(void*) /* How to dispose of the intarray when done */
);
#ifdef __cplusplus
} /* End of the 'extern "C"' block */
#endif
#endif /* _INTARRAY_H_ */