/* ** 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. ** ** This virtual table is used for internal testing of SQLite only. It is ** not recommended for use in production. For a similar virtual table that ** is production-ready, see the "carray" virtual table over in ext/misc. ** ** 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 individual 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. Because of the way virtual tables ** work and the (somewhat goofy) way that the intarray virtual table is ** implemented, it is not allowed to invoke sqlite3_intarray_create(D,N,P) ** more than once with the same D and N values. */ #include "sqlite3.h" #ifndef SQLITE_INTARRAY_H #define SQLITE_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. */ SQLITE_API 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. */ SQLITE_API 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 /* SQLITE_INTARRAY_H */