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-rw-r--r--src/where.c66
1 files changed, 46 insertions, 20 deletions
diff --git a/src/where.c b/src/where.c
index 8ecdd840f..e2a482cf9 100644
--- a/src/where.c
+++ b/src/where.c
@@ -31,8 +31,8 @@ static int whereLoopResize(sqlite3*, WhereLoop*, int);
/*
** Return the estimated number of output rows from a WHERE clause
*/
-u64 sqlite3WhereOutputRowCount(WhereInfo *pWInfo){
- return sqlite3LogEstToInt(pWInfo->nRowOut);
+LogEst sqlite3WhereOutputRowCount(WhereInfo *pWInfo){
+ return pWInfo->nRowOut;
}
/*
@@ -1561,7 +1561,8 @@ static int whereEqualScanEst(
pBuilder->nRecValid = nEq;
whereKeyStats(pParse, p, pRec, 0, a);
- WHERETRACE(0x10,("equality scan regions: %d\n", (int)a[1]));
+ WHERETRACE(0x10,("equality scan regions %s(%d): %d\n",
+ p->zName, nEq-1, (int)a[1]));
*pnRow = a[1];
return rc;
@@ -1736,7 +1737,7 @@ static int whereLoopResize(sqlite3 *db, WhereLoop *p, int n){
if( p->nLSlot>=n ) return SQLITE_OK;
n = (n+7)&~7;
paNew = sqlite3DbMallocRawNN(db, sizeof(p->aLTerm[0])*n);
- if( paNew==0 ) return SQLITE_NOMEM;
+ if( paNew==0 ) return SQLITE_NOMEM_BKPT;
memcpy(paNew, p->aLTerm, sizeof(p->aLTerm[0])*p->nLSlot);
if( p->aLTerm!=p->aLTermSpace ) sqlite3DbFree(db, p->aLTerm);
p->aLTerm = paNew;
@@ -1751,7 +1752,7 @@ static int whereLoopXfer(sqlite3 *db, WhereLoop *pTo, WhereLoop *pFrom){
whereLoopClearUnion(db, pTo);
if( whereLoopResize(db, pTo, pFrom->nLTerm) ){
memset(&pTo->u, 0, sizeof(pTo->u));
- return SQLITE_NOMEM;
+ return SQLITE_NOMEM_BKPT;
}
memcpy(pTo, pFrom, WHERE_LOOP_XFER_SZ);
memcpy(pTo->aLTerm, pFrom->aLTerm, pTo->nLTerm*sizeof(pTo->aLTerm[0]));
@@ -2033,7 +2034,7 @@ static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
if( p==0 ){
/* Allocate a new WhereLoop to add to the end of the list */
*ppPrev = p = sqlite3DbMallocRawNN(db, sizeof(WhereLoop));
- if( p==0 ) return SQLITE_NOMEM;
+ if( p==0 ) return SQLITE_NOMEM_BKPT;
whereLoopInit(p);
p->pNextLoop = 0;
}else{
@@ -2189,7 +2190,7 @@ static int whereLoopAddBtreeIndex(
WhereTerm *pTop = 0, *pBtm = 0; /* Top and bottom range constraints */
pNew = pBuilder->pNew;
- if( db->mallocFailed ) return SQLITE_NOMEM;
+ if( db->mallocFailed ) return SQLITE_NOMEM_BKPT;
assert( (pNew->wsFlags & WHERE_VIRTUALTABLE)==0 );
assert( (pNew->wsFlags & WHERE_TOP_LIMIT)==0 );
@@ -2806,7 +2807,7 @@ static int whereLoopAddVirtual(
pTab = pSrc->pTab;
assert( IsVirtual(pTab) );
pIdxInfo = allocateIndexInfo(pParse, pWC, mUnusable, pSrc,pBuilder->pOrderBy);
- if( pIdxInfo==0 ) return SQLITE_NOMEM;
+ if( pIdxInfo==0 ) return SQLITE_NOMEM_BKPT;
pNew->prereq = 0;
pNew->rSetup = 0;
pNew->wsFlags = WHERE_VIRTUALTABLE;
@@ -2816,7 +2817,7 @@ static int whereLoopAddVirtual(
nConstraint = pIdxInfo->nConstraint;
if( whereLoopResize(db, pNew, nConstraint) ){
sqlite3DbFree(db, pIdxInfo);
- return SQLITE_NOMEM;
+ return SQLITE_NOMEM_BKPT;
}
for(iPhase=0; iPhase<=3; iPhase++){
@@ -3438,6 +3439,7 @@ static const char *wherePathName(WherePath *pPath, int nLoop, WhereLoop *pLast){
** order.
*/
static LogEst whereSortingCost(
+ WhereInfo *pWInfo,
LogEst nRow,
int nOrderBy,
int nSorted
@@ -3458,7 +3460,14 @@ static LogEst whereSortingCost(
LogEst rScale, rSortCost;
assert( nOrderBy>0 && 66==sqlite3LogEst(100) );
rScale = sqlite3LogEst((nOrderBy-nSorted)*100/nOrderBy) - 66;
- rSortCost = nRow + estLog(nRow) + rScale + 16;
+ rSortCost = nRow + rScale + 16;
+
+ /* Multiple by log(M) where M is the number of output rows.
+ ** Use the LIMIT for M if it is smaller */
+ if( (pWInfo->wctrlFlags & WHERE_USE_LIMIT)!=0 && pWInfo->iLimit<nRow ){
+ nRow = pWInfo->iLimit;
+ }
+ rSortCost += estLog(nRow);
return rSortCost;
}
@@ -3521,7 +3530,7 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
nSpace = (sizeof(WherePath)+sizeof(WhereLoop*)*nLoop)*mxChoice*2;
nSpace += sizeof(LogEst) * nOrderBy;
pSpace = sqlite3DbMallocRawNN(db, nSpace);
- if( pSpace==0 ) return SQLITE_NOMEM;
+ if( pSpace==0 ) return SQLITE_NOMEM_BKPT;
aTo = (WherePath*)pSpace;
aFrom = aTo+mxChoice;
memset(aFrom, 0, sizeof(aFrom[0]));
@@ -3576,6 +3585,12 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
if( (pWLoop->prereq & ~pFrom->maskLoop)!=0 ) continue;
if( (pWLoop->maskSelf & pFrom->maskLoop)!=0 ) continue;
+ if( (pWLoop->wsFlags & WHERE_AUTO_INDEX)!=0 && pFrom->nRow<10 ){
+ /* Do not use an automatic index if the this loop is expected
+ ** to run less than 2 times. */
+ assert( 10==sqlite3LogEst(2) );
+ continue;
+ }
/* At this point, pWLoop is a candidate to be the next loop.
** Compute its cost */
rUnsorted = sqlite3LogEstAdd(pWLoop->rSetup,pWLoop->rRun + pFrom->nRow);
@@ -3592,7 +3607,7 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
if( isOrdered>=0 && isOrdered<nOrderBy ){
if( aSortCost[isOrdered]==0 ){
aSortCost[isOrdered] = whereSortingCost(
- nRowEst, nOrderBy, isOrdered
+ pWInfo, nRowEst, nOrderBy, isOrdered
);
}
rCost = sqlite3LogEstAdd(rUnsorted, aSortCost[isOrdered]);
@@ -3991,7 +4006,8 @@ WhereInfo *sqlite3WhereBegin(
ExprList *pOrderBy, /* An ORDER BY (or GROUP BY) clause, or NULL */
ExprList *pResultSet, /* Result set of the query */
u16 wctrlFlags, /* One of the WHERE_* flags defined in sqliteInt.h */
- int iIdxCur /* If WHERE_ONETABLE_ONLY is set, index cursor number */
+ int iAuxArg /* If WHERE_ONETABLE_ONLY is set, index cursor number,
+ ** If WHERE_USE_LIMIT, then the limit amount */
){
int nByteWInfo; /* Num. bytes allocated for WhereInfo struct */
int nTabList; /* Number of elements in pTabList */
@@ -4012,6 +4028,10 @@ WhereInfo *sqlite3WhereBegin(
&& (wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0
));
+ /* Only one of WHERE_ONETABLE_ONLY or WHERE_USE_LIMIT */
+ assert( (wctrlFlags & WHERE_ONETABLE_ONLY)==0
+ || (wctrlFlags & WHERE_USE_LIMIT)==0 );
+
/* Variable initialization */
db = pParse->db;
memset(&sWLB, 0, sizeof(sWLB));
@@ -4065,6 +4085,7 @@ WhereInfo *sqlite3WhereBegin(
pWInfo->pResultSet = pResultSet;
pWInfo->iBreak = pWInfo->iContinue = sqlite3VdbeMakeLabel(v);
pWInfo->wctrlFlags = wctrlFlags;
+ pWInfo->iLimit = iAuxArg;
pWInfo->savedNQueryLoop = pParse->nQueryLoop;
assert( pWInfo->eOnePass==ONEPASS_OFF ); /* ONEPASS defaults to OFF */
pMaskSet = &pWInfo->sMaskSet;
@@ -4145,9 +4166,14 @@ WhereInfo *sqlite3WhereBegin(
}
/* Construct the WhereLoop objects */
- WHERETRACE(0xffff,("*** Optimizer Start *** (wctrlFlags: 0x%x)\n",
- wctrlFlags));
#if defined(WHERETRACE_ENABLED)
+ if( sqlite3WhereTrace & 0xffff ){
+ sqlite3DebugPrintf("*** Optimizer Start *** (wctrlFlags: 0x%x",wctrlFlags);
+ if( wctrlFlags & WHERE_USE_LIMIT ){
+ sqlite3DebugPrintf(", limit: %d", iAuxArg);
+ }
+ sqlite3DebugPrintf(")\n");
+ }
if( sqlite3WhereTrace & 0x100 ){ /* Display all terms of the WHERE clause */
int i;
for(i=0; i<sWLB.pWC->nTerm; i++){
@@ -4330,8 +4356,8 @@ WhereInfo *sqlite3WhereBegin(
Index *pIx = pLoop->u.btree.pIndex;
int iIndexCur;
int op = OP_OpenRead;
- /* iIdxCur is always set if to a positive value if ONEPASS is possible */
- assert( iIdxCur!=0 || (pWInfo->wctrlFlags & WHERE_ONEPASS_DESIRED)==0 );
+ /* iAuxArg is always set if to a positive value if ONEPASS is possible */
+ assert( iAuxArg!=0 || (pWInfo->wctrlFlags & WHERE_ONEPASS_DESIRED)==0 );
if( !HasRowid(pTab) && IsPrimaryKeyIndex(pIx)
&& (wctrlFlags & WHERE_ONETABLE_ONLY)!=0
){
@@ -4341,7 +4367,7 @@ WhereInfo *sqlite3WhereBegin(
op = 0;
}else if( pWInfo->eOnePass!=ONEPASS_OFF ){
Index *pJ = pTabItem->pTab->pIndex;
- iIndexCur = iIdxCur;
+ iIndexCur = iAuxArg;
assert( wctrlFlags & WHERE_ONEPASS_DESIRED );
while( ALWAYS(pJ) && pJ!=pIx ){
iIndexCur++;
@@ -4349,8 +4375,8 @@ WhereInfo *sqlite3WhereBegin(
}
op = OP_OpenWrite;
pWInfo->aiCurOnePass[1] = iIndexCur;
- }else if( iIdxCur && (wctrlFlags & WHERE_ONETABLE_ONLY)!=0 ){
- iIndexCur = iIdxCur;
+ }else if( iAuxArg && (wctrlFlags & WHERE_ONETABLE_ONLY)!=0 ){
+ iIndexCur = iAuxArg;
if( wctrlFlags & WHERE_REOPEN_IDX ) op = OP_ReopenIdx;
}else{
iIndexCur = pParse->nTab++;
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-22 08:40:53 +0000