diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/fkey.c | 10 | ||||
-rw-r--r-- | src/tclsqlite.c | 8 | ||||
-rw-r--r-- | src/where.c | 55 |
3 files changed, 56 insertions, 17 deletions
diff --git a/src/fkey.c b/src/fkey.c index f91a6de54..0012768a3 100644 --- a/src/fkey.c +++ b/src/fkey.c @@ -633,10 +633,12 @@ static void fkScanChildren( /* Create VDBE to loop through the entries in pSrc that match the WHERE ** clause. For each row found, increment either the deferred or immediate ** foreign key constraint counter. */ - pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0, 0, 0); - sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, nIncr); - if( pWInfo ){ - sqlite3WhereEnd(pWInfo); + if( pParse->nErr==0 ){ + pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0, 0, 0); + sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, nIncr); + if( pWInfo ){ + sqlite3WhereEnd(pWInfo); + } } /* Clean up the WHERE clause constructed above. */ diff --git a/src/tclsqlite.c b/src/tclsqlite.c index 754775e8e..bb7c9e5b8 100644 --- a/src/tclsqlite.c +++ b/src/tclsqlite.c @@ -161,6 +161,7 @@ struct SqliteDb { int nStmt; /* Number of statements in stmtList */ IncrblobChannel *pIncrblob;/* Linked list of open incrblob channels */ int nStep, nSort, nIndex; /* Statistics for most recent operation */ + int nVMStep; /* Another statistic for most recent operation */ int nTransaction; /* Number of nested [transaction] methods */ int openFlags; /* Flags used to open. (SQLITE_OPEN_URI) */ #ifdef SQLITE_TEST @@ -1588,6 +1589,7 @@ static int dbEvalStep(DbEvalContext *p){ pDb->nStep = sqlite3_stmt_status(pStmt,SQLITE_STMTSTATUS_FULLSCAN_STEP,1); pDb->nSort = sqlite3_stmt_status(pStmt,SQLITE_STMTSTATUS_SORT,1); pDb->nIndex = sqlite3_stmt_status(pStmt,SQLITE_STMTSTATUS_AUTOINDEX,1); + pDb->nVMStep = sqlite3_stmt_status(pStmt,SQLITE_STMTSTATUS_VM_STEP,1); dbReleaseColumnNames(p); p->pPreStmt = 0; @@ -2855,7 +2857,7 @@ static int SQLITE_TCLAPI DbObjCmd( } /* - ** $db status (step|sort|autoindex) + ** $db status (step|sort|autoindex|vmstep) ** ** Display SQLITE_STMTSTATUS_FULLSCAN_STEP or ** SQLITE_STMTSTATUS_SORT for the most recent eval. @@ -2874,9 +2876,11 @@ static int SQLITE_TCLAPI DbObjCmd( v = pDb->nSort; }else if( strcmp(zOp, "autoindex")==0 ){ v = pDb->nIndex; + }else if( strcmp(zOp, "vmstep")==0 ){ + v = pDb->nVMStep; }else{ Tcl_AppendResult(interp, - "bad argument: should be autoindex, step, or sort", + "bad argument: should be autoindex, step, sort or vmstep", (char*)0); return TCL_ERROR; } diff --git a/src/where.c b/src/where.c index 99b0df4e5..1cd5d7033 100644 --- a/src/where.c +++ b/src/where.c @@ -4295,6 +4295,31 @@ static int whereShortCut(WhereLoopBuilder *pBuilder){ } /* +** Helper function for exprIsDeterministic(). +*/ +static int exprNodeIsDeterministic(Walker *pWalker, Expr *pExpr){ + if( pExpr->op==TK_FUNCTION && ExprHasProperty(pExpr, EP_ConstFunc)==0 ){ + pWalker->eCode = 0; + return WRC_Abort; + } + return WRC_Continue; +} + +/* +** Return true if the expression contains no non-deterministic SQL +** functions. Do not consider non-deterministic SQL functions that are +** part of sub-select statements. +*/ +static int exprIsDeterministic(Expr *p){ + Walker w; + memset(&w, 0, sizeof(w)); + w.eCode = 1; + w.xExprCallback = exprNodeIsDeterministic; + sqlite3WalkExpr(&w, p); + return w.eCode; +} + +/* ** Generate the beginning of the loop used for WHERE clause processing. ** The return value is a pointer to an opaque structure that contains ** information needed to terminate the loop. Later, the calling routine @@ -4492,17 +4517,6 @@ WhereInfo *sqlite3WhereBegin( sqlite3WhereClauseInit(&pWInfo->sWC, pWInfo); sqlite3WhereSplit(&pWInfo->sWC, pWhere, TK_AND); - /* Special case: a WHERE clause that is constant. Evaluate the - ** expression and either jump over all of the code or fall thru. - */ - for(ii=0; ii<sWLB.pWC->nTerm; ii++){ - if( nTabList==0 || sqlite3ExprIsConstantNotJoin(sWLB.pWC->a[ii].pExpr) ){ - sqlite3ExprIfFalse(pParse, sWLB.pWC->a[ii].pExpr, pWInfo->iBreak, - SQLITE_JUMPIFNULL); - sWLB.pWC->a[ii].wtFlags |= TERM_CODED; - } - } - /* Special case: No FROM clause */ if( nTabList==0 ){ @@ -4541,6 +4555,25 @@ WhereInfo *sqlite3WhereBegin( sqlite3WhereExprAnalyze(pTabList, &pWInfo->sWC); if( db->mallocFailed ) goto whereBeginError; + /* Special case: WHERE terms that do not refer to any tables in the join + ** (constant expressions). Evaluate each such term, and jump over all the + ** generated code if the result is not true. + ** + ** Do not do this if the expression contains non-deterministic functions + ** that are not within a sub-select. This is not strictly required, but + ** preserves SQLite's legacy behaviour in the following two cases: + ** + ** FROM ... WHERE random()>0; -- eval random() once per row + ** FROM ... WHERE (SELECT random())>0; -- eval random() once overall + */ + for(ii=0; ii<sWLB.pWC->nTerm; ii++){ + WhereTerm *pT = &sWLB.pWC->a[ii]; + if( pT->prereqAll==0 && (nTabList==0 || exprIsDeterministic(pT->pExpr)) ){ + sqlite3ExprIfFalse(pParse, pT->pExpr, pWInfo->iBreak, SQLITE_JUMPIFNULL); + pT->wtFlags |= TERM_CODED; + } + } + if( wctrlFlags & WHERE_WANT_DISTINCT ){ if( isDistinctRedundant(pParse, pTabList, &pWInfo->sWC, pResultSet) ){ /* The DISTINCT marking is pointless. Ignore it. */ |