1 /* 2 ** 2009 November 10 3 ** 4 ** The author disclaims copyright to this source code. In place of 5 ** a legal notice, here is a blessing: 6 ** 7 ** May you do good and not evil. 8 ** May you find forgiveness for yourself and forgive others. 9 ** May you share freely, never taking more than you give. 10 ** 11 ************************************************************************* 12 ** 13 ** This is the C-language interface definition for the "intarray" or 14 ** integer array virtual table for SQLite. 15 ** 16 ** The intarray virtual table is designed to facilitate using an 17 ** array of integers as the right-hand side of an IN operator. So 18 ** instead of doing a prepared statement like this: 19 ** 20 ** SELECT * FROM table WHERE x IN (?,?,?,...,?); 21 ** 22 ** And then binding indivdual integers to each of ? slots, a C-language 23 ** application can create an intarray object (named "ex1" in the following 24 ** example), prepare a statement like this: 25 ** 26 ** SELECT * FROM table WHERE x IN ex1; 27 ** 28 ** Then bind an ordinary C/C++ array of integer values to the ex1 object 29 ** to run the statement. 30 ** 31 ** USAGE: 32 ** 33 ** One or more intarray objects can be created as follows: 34 ** 35 ** sqlite3_intarray *p1, *p2, *p3; 36 ** sqlite3_intarray_create(db, "ex1", &p1); 37 ** sqlite3_intarray_create(db, "ex2", &p2); 38 ** sqlite3_intarray_create(db, "ex3", &p3); 39 ** 40 ** Each call to sqlite3_intarray_create() generates a new virtual table 41 ** module and a singleton of that virtual table module in the TEMP 42 ** database. Both the module and the virtual table instance use the 43 ** name given by the second parameter. The virtual tables can then be 44 ** used in prepared statements: 45 ** 46 ** SELECT * FROM t1, t2, t3 47 ** WHERE t1.x IN ex1 48 ** AND t2.y IN ex2 49 ** AND t3.z IN ex3; 50 ** 51 ** Each integer array is initially empty. New arrays can be bound to 52 ** an integer array as follows: 53 ** 54 ** sqlite3_int64 a1[] = { 1, 2, 3, 4 }; 55 ** sqlite3_int64 a2[] = { 5, 6, 7, 8, 9, 10, 11 }; 56 ** sqlite3_int64 *a3 = sqlite3_malloc( 100*sizeof(sqlite3_int64) ); 57 ** // Fill in content of a3[] 58 ** sqlite3_intarray_bind(p1, 4, a1, 0); 59 ** sqlite3_intarray_bind(p2, 7, a2, 0); 60 ** sqlite3_intarray_bind(p3, 100, a3, sqlite3_free); 61 ** 62 ** A single intarray object can be rebound multiple times. But do not 63 ** attempt to change the bindings of an intarray while it is in the middle 64 ** of a query. 65 ** 66 ** The array that holds the integers is automatically freed by the function 67 ** in the fourth parameter to sqlite3_intarray_bind() when the array is no 68 ** longer needed. The application must not change the intarray values 69 ** while an intarray is in the middle of a query. 70 ** 71 ** The intarray object is automatically destroyed when its corresponding 72 ** virtual table is dropped. Since the virtual tables are created in the 73 ** TEMP database, they are automatically dropped when the database connection 74 ** closes so the application does not normally need to take any special 75 ** action to free the intarray objects. 76 */ 77 #include "sqlite3.h" 78 79 /* 80 ** Make sure we can call this stuff from C++. 81 */ 82 #ifdef __cplusplus 83 extern "C" { 84 #endif 85 86 /* 87 ** An sqlite3_intarray is an abstract type to stores an instance of 88 ** an integer array. 89 */ 90 typedef struct sqlite3_intarray sqlite3_intarray; 91 92 /* 93 ** Invoke this routine to create a specific instance of an intarray object. 94 ** The new intarray object is returned by the 3rd parameter. 95 ** 96 ** Each intarray object corresponds to a virtual table in the TEMP table 97 ** with a name of zName. 98 ** 99 ** Destroy the intarray object by dropping the virtual table. If not done 100 ** explicitly by the application, the virtual table will be dropped implicitly 101 ** by the system when the database connection is closed. 102 */ 103 int sqlite3_intarray_create( 104 sqlite3 *db, 105 const char *zName, 106 sqlite3_intarray **ppReturn 107 ); 108 109 /* 110 ** Bind a new array array of integers to a specific intarray object. 111 ** 112 ** The array of integers bound must be unchanged for the duration of 113 ** any query against the corresponding virtual table. If the integer 114 ** array does change or is deallocated undefined behavior will result. 115 */ 116 int sqlite3_intarray_bind( 117 sqlite3_intarray *pIntArray, /* The intarray object to bind to */ 118 int nElements, /* Number of elements in the intarray */ 119 sqlite3_int64 *aElements, /* Content of the intarray */ 120 void (*xFree)(void*) /* How to dispose of the intarray when done */ 121 ); 122 123 #ifdef __cplusplus 124 } /* End of the 'extern "C"' block */ 125 #endif 126