An instance of the virtual machine.
This structure contains the complete state of the virtual machine.
struct Vdbe { sqlite3 *db; /* The database connection that owns this statement */ Op *aOp; /* Space to hold the virtual machine's program */ Mem *aMem; /* The memory locations */ Mem **apArg; /* Arguments to currently executing user function */ Mem *aColName; /* Column names to return */ Mem *pResultSet; /* Pointer to an array of results */ Parse *pParse; /* Parsing context used to create this Vdbe */ int nMem; /* Number of memory locations currently allocated */ int nOp; /* Number of instructions in the program */ int nCursor; /* Number of slots in apCsr[] */ u32 magic; /* Magic number for sanity checking */ char *zErrMsg; /* Error message written here */ Vdbe *pPrev,*pNext; /* Linked list of VDBEs with the same Vdbe.db */ VdbeCursor **apCsr; /* One element of this array for each open cursor */ Mem *aVar; /* Values for the OP_Variable opcode. */ char **azVar; /* Name of variables */ ynVar nVar; /* Number of entries in aVar[] */ ynVar nzVar; /* Number of entries in azVar[] */ u32 cacheCtr; /* VdbeCursor row cache generation counter */ int pc; /* The program counter */ int rc; /* Value to return */ #ifdef SQLITE_DEBUG int rcApp; /* errcode set by sqlite3_result_error_code() */ #endif u16 nResColumn; /* Number of columns in one row of the result set */ u8 errorAction; /* Recovery action to do in case of an error */ u8 minWriteFileFormat; /* Minimum file format for writable database files */ bft explain:2; /* True if EXPLAIN present on SQL command */ bft changeCntOn:1; /* True to update the change-counter */ bft expired:1; /* True if the VM needs to be recompiled */ bft runOnlyOnce:1; /* Automatically expire on reset */ bft usesStmtJournal:1; /* True if uses a statement journal */ bft readOnly:1; /* True for statements that do not write */ bft bIsReader:1; /* True for statements that read */ bft isPrepareV2:1; /* True if prepared with prepare_v2() */ bft doingRerun:1; /* True if rerunning after an auto-reprepare */ int nChange; /* Number of db changes made since last reset */ yDbMask btreeMask; /* Bitmask of db->aDb[] entries referenced */ yDbMask lockMask; /* Subset of btreeMask that requires a lock */ int iStatement; /* Statement number (or 0 if has not opened stmt) */ u32 aCounter[5]; /* Counters used by sqlite3_stmt_status() */ #ifndef SQLITE_OMIT_TRACE i64 startTime; /* Time when query started - used for profiling */ #endif i64 iCurrentTime; /* Value of julianday('now') for this statement */ i64 nFkConstraint; /* Number of imm. FK constraints this VM */ i64 nStmtDefCons; /* Number of def. constraints when stmt started */ i64 nStmtDefImmCons; /* Number of def. imm constraints when stmt started */ char *zSql; /* Text of the SQL statement that generated this */ void *pFree; /* Free this when deleting the vdbe */ VdbeFrame *pFrame; /* Parent frame */ VdbeFrame *pDelFrame; /* List of frame objects to free on VM reset */ int nFrame; /* Number of frames in pFrame list */ u32 expmask; /* Binding to these vars invalidates VM */ SubProgram *pProgram; /* Linked list of all sub-programs used by VM */ int nOnceFlag; /* Size of array aOnceFlag[] */ u8 *aOnceFlag; /* Flags for OP_Once */ AuxData *pAuxData; /* Linked list of auxdata allocations */ #ifdef SQLITE_ENABLE_STMT_SCANSTATUS i64 *anExec; /* Number of times each op has been executed */ int nScan; /* Entries in aScan[] */ ScanStatus *aScan; /* Scan definitions for sqlite3_stmt_scanstatus() */ #endif };