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-rw-r--r--src/where.c319
1 files changed, 248 insertions, 71 deletions
diff --git a/src/where.c b/src/where.c
index 213df4223..9850d22cc 100644
--- a/src/where.c
+++ b/src/where.c
@@ -678,12 +678,22 @@ static void translateColumnToCopy(
for(; iStart<iEnd; iStart++, pOp++){
if( pOp->p1!=iTabCur ) continue;
if( pOp->opcode==OP_Column ){
+#ifdef SQLITE_DEBUG
+ if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
+ printf("TRANSLATE OP_Column to OP_Copy at %d\n", iStart);
+ }
+#endif
pOp->opcode = OP_Copy;
pOp->p1 = pOp->p2 + iRegister;
pOp->p2 = pOp->p3;
pOp->p3 = 0;
pOp->p5 = 2; /* Cause the MEM_Subtype flag to be cleared */
}else if( pOp->opcode==OP_Rowid ){
+#ifdef SQLITE_DEBUG
+ if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
+ printf("TRANSLATE OP_Rowid to OP_Sequence at %d\n", iStart);
+ }
+#endif
pOp->opcode = OP_Sequence;
pOp->p1 = iAutoidxCur;
#ifdef SQLITE_ALLOW_ROWID_IN_VIEW
@@ -1142,13 +1152,17 @@ static SQLITE_NOINLINE void sqlite3ConstructBloomFilter(
WhereLoop *pLoop = pLevel->pWLoop; /* The loop being coded */
int iCur; /* Cursor for table getting the filter */
IndexedExpr *saved_pIdxEpr; /* saved copy of Parse.pIdxEpr */
+ IndexedExpr *saved_pIdxPartExpr; /* saved copy of Parse.pIdxPartExpr */
saved_pIdxEpr = pParse->pIdxEpr;
+ saved_pIdxPartExpr = pParse->pIdxPartExpr;
pParse->pIdxEpr = 0;
+ pParse->pIdxPartExpr = 0;
assert( pLoop!=0 );
assert( v!=0 );
assert( pLoop->wsFlags & WHERE_BLOOMFILTER );
+ assert( (pLoop->wsFlags & WHERE_IDX_ONLY)==0 );
addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
do{
@@ -1238,6 +1252,7 @@ static SQLITE_NOINLINE void sqlite3ConstructBloomFilter(
}while( iLevel < pWInfo->nLevel );
sqlite3VdbeJumpHere(v, addrOnce);
pParse->pIdxEpr = saved_pIdxEpr;
+ pParse->pIdxPartExpr = saved_pIdxPartExpr;
}
@@ -2005,7 +2020,8 @@ static int whereRangeScanEst(
** sample, then assume they are 4x more selective. This brings
** the estimated selectivity more in line with what it would be
** if estimated without the use of STAT4 tables. */
- if( iLwrIdx==iUprIdx ) nNew -= 20; assert( 20==sqlite3LogEst(4) );
+ if( iLwrIdx==iUprIdx ){ nNew -= 20; }
+ assert( 20==sqlite3LogEst(4) );
}else{
nNew = 10; assert( 10==sqlite3LogEst(2) );
}
@@ -2229,17 +2245,34 @@ void sqlite3WhereClausePrint(WhereClause *pWC){
#ifdef WHERETRACE_ENABLED
/*
** Print a WhereLoop object for debugging purposes
+**
+** Format example:
+**
+** .--- Position in WHERE clause rSetup, rRun, nOut ---.
+** | |
+** | .--- selfMask nTerm ------. |
+** | | | |
+** | | .-- prereq Idx wsFlags----. | |
+** | | | Name | | |
+** | | | __|__ nEq ---. ___|__ | __|__
+** | / \ / \ / \ | / \ / \ / \
+** 1.002.001 t2.t2xy 2 f 010241 N 2 cost 0,56,31
*/
-void sqlite3WhereLoopPrint(WhereLoop *p, WhereClause *pWC){
- WhereInfo *pWInfo = pWC->pWInfo;
- int nb = 1+(pWInfo->pTabList->nSrc+3)/4;
- SrcItem *pItem = pWInfo->pTabList->a + p->iTab;
- Table *pTab = pItem->pTab;
- Bitmask mAll = (((Bitmask)1)<<(nb*4)) - 1;
- sqlite3DebugPrintf("%c%2d.%0*llx.%0*llx", p->cId,
- p->iTab, nb, p->maskSelf, nb, p->prereq & mAll);
- sqlite3DebugPrintf(" %12s",
- pItem->zAlias ? pItem->zAlias : pTab->zName);
+void sqlite3WhereLoopPrint(const WhereLoop *p, const WhereClause *pWC){
+ if( pWC ){
+ WhereInfo *pWInfo = pWC->pWInfo;
+ int nb = 1+(pWInfo->pTabList->nSrc+3)/4;
+ SrcItem *pItem = pWInfo->pTabList->a + p->iTab;
+ Table *pTab = pItem->pTab;
+ Bitmask mAll = (((Bitmask)1)<<(nb*4)) - 1;
+ sqlite3DebugPrintf("%c%2d.%0*llx.%0*llx", p->cId,
+ p->iTab, nb, p->maskSelf, nb, p->prereq & mAll);
+ sqlite3DebugPrintf(" %12s",
+ pItem->zAlias ? pItem->zAlias : pTab->zName);
+ }else{
+ sqlite3DebugPrintf("%c%2d.%03llx.%03llx %c%d",
+ p->cId, p->iTab, p->maskSelf, p->prereq & 0xfff, p->cId, p->iTab);
+ }
if( (p->wsFlags & WHERE_VIRTUALTABLE)==0 ){
const char *zName;
if( p->u.btree.pIndex && (zName = p->u.btree.pIndex->zName)!=0 ){
@@ -2276,6 +2309,15 @@ void sqlite3WhereLoopPrint(WhereLoop *p, WhereClause *pWC){
}
}
}
+void sqlite3ShowWhereLoop(const WhereLoop *p){
+ if( p ) sqlite3WhereLoopPrint(p, 0);
+}
+void sqlite3ShowWhereLoopList(const WhereLoop *p){
+ while( p ){
+ sqlite3ShowWhereLoop(p);
+ p = p->pNextLoop;
+ }
+}
#endif
/*
@@ -2388,46 +2430,60 @@ static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
}
/*
-** Return TRUE if all of the following are true:
-**
-** (1) X has the same or lower cost, or returns the same or fewer rows,
-** than Y.
-** (2) X uses fewer WHERE clause terms than Y
-** (3) Every WHERE clause term used by X is also used by Y
-** (4) X skips at least as many columns as Y
-** (5) If X is a covering index, than Y is too
-**
-** Conditions (2) and (3) mean that X is a "proper subset" of Y.
-** If X is a proper subset of Y then Y is a better choice and ought
-** to have a lower cost. This routine returns TRUE when that cost
-** relationship is inverted and needs to be adjusted. Constraint (4)
-** was added because if X uses skip-scan less than Y it still might
-** deserve a lower cost even if it is a proper subset of Y. Constraint (5)
-** was added because a covering index probably deserves to have a lower cost
-** than a non-covering index even if it is a proper subset.
+** Return TRUE if X is a proper subset of Y but is of equal or less cost.
+** In other words, return true if all constraints of X are also part of Y
+** and Y has additional constraints that might speed the search that X lacks
+** but the cost of running X is not more than the cost of running Y.
+**
+** In other words, return true if the cost relationwship between X and Y
+** is inverted and needs to be adjusted.
+**
+** Case 1:
+**
+** (1a) X and Y use the same index.
+** (1b) X has fewer == terms than Y
+** (1c) Neither X nor Y use skip-scan
+** (1d) X does not have a a greater cost than Y
+**
+** Case 2:
+**
+** (2a) X has the same or lower cost, or returns the same or fewer rows,
+** than Y.
+** (2b) X uses fewer WHERE clause terms than Y
+** (2c) Every WHERE clause term used by X is also used by Y
+** (2d) X skips at least as many columns as Y
+** (2e) If X is a covering index, than Y is too
*/
static int whereLoopCheaperProperSubset(
const WhereLoop *pX, /* First WhereLoop to compare */
const WhereLoop *pY /* Compare against this WhereLoop */
){
int i, j;
+ if( pX->rRun>pY->rRun && pX->nOut>pY->nOut ) return 0; /* (1d) and (2a) */
+ assert( (pX->wsFlags & WHERE_VIRTUALTABLE)==0 );
+ assert( (pY->wsFlags & WHERE_VIRTUALTABLE)==0 );
+ if( pX->u.btree.nEq < pY->u.btree.nEq /* (1b) */
+ && pX->u.btree.pIndex==pY->u.btree.pIndex /* (1a) */
+ && pX->nSkip==0 && pY->nSkip==0 /* (1c) */
+ ){
+ return 1; /* Case 1 is true */
+ }
if( pX->nLTerm-pX->nSkip >= pY->nLTerm-pY->nSkip ){
- return 0; /* X is not a subset of Y */
+ return 0; /* (2b) */
}
- if( pX->rRun>pY->rRun && pX->nOut>pY->nOut ) return 0;
- if( pY->nSkip > pX->nSkip ) return 0;
+ if( pY->nSkip > pX->nSkip ) return 0; /* (2d) */
for(i=pX->nLTerm-1; i>=0; i--){
if( pX->aLTerm[i]==0 ) continue;
for(j=pY->nLTerm-1; j>=0; j--){
if( pY->aLTerm[j]==pX->aLTerm[i] ) break;
}
- if( j<0 ) return 0; /* X not a subset of Y since term X[i] not used by Y */
+ if( j<0 ) return 0; /* (2c) */
}
if( (pX->wsFlags&WHERE_IDX_ONLY)!=0
&& (pY->wsFlags&WHERE_IDX_ONLY)==0 ){
- return 0; /* Constraint (5) */
+ return 0; /* (2e) */
}
- return 1; /* All conditions meet */
+ return 1; /* Case 2 is true */
}
/*
@@ -2917,7 +2973,12 @@ static int whereLoopAddBtreeIndex(
assert( pNew->u.btree.nBtm==0 );
opMask = WO_EQ|WO_IN|WO_GT|WO_GE|WO_LT|WO_LE|WO_ISNULL|WO_IS;
}
- if( pProbe->bUnordered ) opMask &= ~(WO_GT|WO_GE|WO_LT|WO_LE);
+ if( pProbe->bUnordered || pProbe->bLowQual ){
+ if( pProbe->bUnordered ) opMask &= ~(WO_GT|WO_GE|WO_LT|WO_LE);
+ if( pProbe->bLowQual && pSrc->fg.isIndexedBy==0 ){
+ opMask &= ~(WO_EQ|WO_IN|WO_IS);
+ }
+ }
assert( pNew->u.btree.nEq<pProbe->nColumn );
assert( pNew->u.btree.nEq<pProbe->nKeyCol
@@ -3303,7 +3364,9 @@ static int indexMightHelpWithOrderBy(
for(ii=0; ii<pOB->nExpr; ii++){
Expr *pExpr = sqlite3ExprSkipCollateAndLikely(pOB->a[ii].pExpr);
if( NEVER(pExpr==0) ) continue;
- if( pExpr->op==TK_COLUMN && pExpr->iTable==iCursor ){
+ if( (pExpr->op==TK_COLUMN || pExpr->op==TK_AGG_COLUMN)
+ && pExpr->iTable==iCursor
+ ){
if( pExpr->iColumn<0 ) return 1;
for(jj=0; jj<pIndex->nKeyCol; jj++){
if( pExpr->iColumn==pIndex->aiColumn[jj] ) return 1;
@@ -3498,6 +3561,100 @@ static SQLITE_NOINLINE u32 whereIsCoveringIndex(
}
/*
+** This is an sqlite3ParserAddCleanup() callback that is invoked to
+** free the Parse->pIdxEpr list when the Parse object is destroyed.
+*/
+static void whereIndexedExprCleanup(sqlite3 *db, void *pObject){
+ IndexedExpr **pp = (IndexedExpr**)pObject;
+ while( *pp!=0 ){
+ IndexedExpr *p = *pp;
+ *pp = p->pIENext;
+ sqlite3ExprDelete(db, p->pExpr);
+ sqlite3DbFreeNN(db, p);
+ }
+}
+
+/*
+** This function is called for a partial index - one with a WHERE clause - in
+** two scenarios. In both cases, it determines whether or not the WHERE
+** clause on the index implies that a column of the table may be safely
+** replaced by a constant expression. For example, in the following
+** SELECT:
+**
+** CREATE INDEX i1 ON t1(b, c) WHERE a=<expr>;
+** SELECT a, b, c FROM t1 WHERE a=<expr> AND b=?;
+**
+** The "a" in the select-list may be replaced by <expr>, iff:
+**
+** (a) <expr> is a constant expression, and
+** (b) The (a=<expr>) comparison uses the BINARY collation sequence, and
+** (c) Column "a" has an affinity other than NONE or BLOB.
+**
+** If argument pItem is NULL, then pMask must not be NULL. In this case this
+** function is being called as part of determining whether or not pIdx
+** is a covering index. This function clears any bits in (*pMask)
+** corresponding to columns that may be replaced by constants as described
+** above.
+**
+** Otherwise, if pItem is not NULL, then this function is being called
+** as part of coding a loop that uses index pIdx. In this case, add entries
+** to the Parse.pIdxPartExpr list for each column that can be replaced
+** by a constant.
+*/
+static void wherePartIdxExpr(
+ Parse *pParse, /* Parse context */
+ Index *pIdx, /* Partial index being processed */
+ Expr *pPart, /* WHERE clause being processed */
+ Bitmask *pMask, /* Mask to clear bits in */
+ int iIdxCur, /* Cursor number for index */
+ SrcItem *pItem /* The FROM clause entry for the table */
+){
+ assert( pItem==0 || (pItem->fg.jointype & JT_RIGHT)==0 );
+ assert( (pItem==0 || pMask==0) && (pMask!=0 || pItem!=0) );
+
+ if( pPart->op==TK_AND ){
+ wherePartIdxExpr(pParse, pIdx, pPart->pRight, pMask, iIdxCur, pItem);
+ pPart = pPart->pLeft;
+ }
+
+ if( (pPart->op==TK_EQ || pPart->op==TK_IS) ){
+ Expr *pLeft = pPart->pLeft;
+ Expr *pRight = pPart->pRight;
+ u8 aff;
+
+ if( pLeft->op!=TK_COLUMN ) return;
+ if( !sqlite3ExprIsConstant(pRight) ) return;
+ if( !sqlite3IsBinary(sqlite3ExprCompareCollSeq(pParse, pPart)) ) return;
+ if( pLeft->iColumn<0 ) return;
+ aff = pIdx->pTable->aCol[pLeft->iColumn].affinity;
+ if( aff>=SQLITE_AFF_TEXT ){
+ if( pItem ){
+ sqlite3 *db = pParse->db;
+ IndexedExpr *p = (IndexedExpr*)sqlite3DbMallocRaw(db, sizeof(*p));
+ if( p ){
+ int bNullRow = (pItem->fg.jointype&(JT_LEFT|JT_LTORJ))!=0;
+ p->pExpr = sqlite3ExprDup(db, pRight, 0);
+ p->iDataCur = pItem->iCursor;
+ p->iIdxCur = iIdxCur;
+ p->iIdxCol = pLeft->iColumn;
+ p->bMaybeNullRow = bNullRow;
+ p->pIENext = pParse->pIdxPartExpr;
+ p->aff = aff;
+ pParse->pIdxPartExpr = p;
+ if( p->pIENext==0 ){
+ void *pArg = (void*)&pParse->pIdxPartExpr;
+ sqlite3ParserAddCleanup(pParse, whereIndexedExprCleanup, pArg);
+ }
+ }
+ }else if( pLeft->iColumn<(BMS-1) ){
+ *pMask &= ~((Bitmask)1 << pLeft->iColumn);
+ }
+ }
+ }
+}
+
+
+/*
** Add all WhereLoop objects for a single table of the join where the table
** is identified by pBuilder->pNew->iTab. That table is guaranteed to be
** a b-tree table, not a virtual table.
@@ -3700,9 +3857,6 @@ static int whereLoopAddBtree(
#else
pNew->rRun = rSize + 16;
#endif
- if( IsView(pTab) || (pTab->tabFlags & TF_Ephemeral)!=0 ){
- pNew->wsFlags |= WHERE_VIEWSCAN;
- }
ApplyCostMultiplier(pNew->rRun, pTab->costMult);
whereLoopOutputAdjust(pWC, pNew, rSize);
rc = whereLoopInsert(pBuilder, pNew);
@@ -3715,6 +3869,11 @@ static int whereLoopAddBtree(
pNew->wsFlags = WHERE_IDX_ONLY | WHERE_INDEXED;
}else{
m = pSrc->colUsed & pProbe->colNotIdxed;
+ if( pProbe->pPartIdxWhere ){
+ wherePartIdxExpr(
+ pWInfo->pParse, pProbe, pProbe->pPartIdxWhere, &m, 0, 0
+ );
+ }
pNew->wsFlags = WHERE_INDEXED;
if( m==TOPBIT || (pProbe->bHasExpr && !pProbe->bHasVCol && m!=0) ){
u32 isCov = whereIsCoveringIndex(pWInfo, pProbe, pSrc->iCursor);
@@ -3813,7 +3972,7 @@ static int whereLoopAddBtree(
** unique index is used (making the index functionally non-unique)
** then the sqlite_stat1 data becomes important for scoring the
** plan */
- pTab->tabFlags |= TF_StatsUsed;
+ pTab->tabFlags |= TF_MaybeReanalyze;
}
#ifdef SQLITE_ENABLE_STAT4
sqlite3Stat4ProbeFree(pBuilder->pRec);
@@ -4097,7 +4256,7 @@ int sqlite3_vtab_rhs_value(
sqlite3_value *pVal = 0;
int rc = SQLITE_OK;
if( iCons<0 || iCons>=pIdxInfo->nConstraint ){
- rc = SQLITE_MISUSE; /* EV: R-30545-25046 */
+ rc = SQLITE_MISUSE_BKPT; /* EV: R-30545-25046 */
}else{
if( pH->aRhs[iCons]==0 ){
WhereTerm *pTerm = &pH->pWC->a[pIdxInfo->aConstraint[iCons].iTermOffset];
@@ -5121,14 +5280,6 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
rUnsorted -= 2; /* TUNING: Slight bias in favor of no-sort plans */
}
- /* TUNING: A full-scan of a VIEW or subquery in the outer loop
- ** is not so bad. */
- if( iLoop==0 && (pWLoop->wsFlags & WHERE_VIEWSCAN)!=0 && nLoop>1 ){
- rCost += -10;
- nOut += -30;
- WHERETRACE(0x80,("VIEWSCAN cost reduction for %c\n",pWLoop->cId));
- }
-
/* Check to see if pWLoop should be added to the set of
** mxChoice best-so-far paths.
**
@@ -5315,10 +5466,9 @@ static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
if( pFrom->isOrdered==pWInfo->pOrderBy->nExpr ){
pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
}
- if( pWInfo->pSelect->pOrderBy
- && pWInfo->nOBSat > pWInfo->pSelect->pOrderBy->nExpr ){
- pWInfo->nOBSat = pWInfo->pSelect->pOrderBy->nExpr;
- }
+ /* vvv--- See check-in [12ad822d9b827777] on 2023-03-16 ---vvv */
+ assert( pWInfo->pSelect->pOrderBy==0
+ || pWInfo->nOBSat <= pWInfo->pSelect->pOrderBy->nExpr );
}else{
pWInfo->revMask = pFrom->revLoop;
if( pWInfo->nOBSat<=0 ){
@@ -5657,7 +5807,7 @@ static SQLITE_NOINLINE void whereCheckIfBloomFilterIsUseful(
SrcItem *pItem = &pWInfo->pTabList->a[pLoop->iTab];
Table *pTab = pItem->pTab;
if( (pTab->tabFlags & TF_HasStat1)==0 ) break;
- pTab->tabFlags |= TF_StatsUsed;
+ pTab->tabFlags |= TF_MaybeReanalyze;
if( i>=1
&& (pLoop->wsFlags & reqFlags)==reqFlags
/* vvvvvv--- Always the case if WHERE_COLUMN_EQ is defined */
@@ -5679,20 +5829,6 @@ static SQLITE_NOINLINE void whereCheckIfBloomFilterIsUseful(
}
/*
-** This is an sqlite3ParserAddCleanup() callback that is invoked to
-** free the Parse->pIdxEpr list when the Parse object is destroyed.
-*/
-static void whereIndexedExprCleanup(sqlite3 *db, void *pObject){
- Parse *pParse = (Parse*)pObject;
- while( pParse->pIdxEpr!=0 ){
- IndexedExpr *p = pParse->pIdxEpr;
- pParse->pIdxEpr = p->pIENext;
- sqlite3ExprDelete(db, p->pExpr);
- sqlite3DbFreeNN(db, p);
- }
-}
-
-/*
** The index pIdx is used by a query and contains one or more expressions.
** In other words pIdx is an index on an expression. iIdxCur is the cursor
** number for the index and iDataCur is the cursor number for the corresponding
@@ -5731,6 +5867,20 @@ static SQLITE_NOINLINE void whereAddIndexedExpr(
continue;
}
if( sqlite3ExprIsConstant(pExpr) ) continue;
+ if( pExpr->op==TK_FUNCTION ){
+ /* Functions that might set a subtype should not be replaced by the
+ ** value taken from an expression index since the index omits the
+ ** subtype. https://sqlite.org/forum/forumpost/68d284c86b082c3e */
+ int n;
+ FuncDef *pDef;
+ sqlite3 *db = pParse->db;
+ assert( ExprUseXList(pExpr) );
+ n = pExpr->x.pList ? pExpr->x.pList->nExpr : 0;
+ pDef = sqlite3FindFunction(db, pExpr->u.zToken, n, ENC(db), 0);
+ if( pDef==0 || (pDef->funcFlags & SQLITE_RESULT_SUBTYPE)!=0 ){
+ continue;
+ }
+ }
p = sqlite3DbMallocRaw(pParse->db, sizeof(IndexedExpr));
if( p==0 ) break;
p->pIENext = pParse->pIdxEpr;
@@ -5753,7 +5903,8 @@ static SQLITE_NOINLINE void whereAddIndexedExpr(
#endif
pParse->pIdxEpr = p;
if( p->pIENext==0 ){
- sqlite3ParserAddCleanup(pParse, whereIndexedExprCleanup, pParse);
+ void *pArg = (void*)&pParse->pIdxEpr;
+ sqlite3ParserAddCleanup(pParse, whereIndexedExprCleanup, pArg);
}
}
}
@@ -5908,7 +6059,10 @@ WhereInfo *sqlite3WhereBegin(
/* An ORDER/GROUP BY clause of more than 63 terms cannot be optimized */
testcase( pOrderBy && pOrderBy->nExpr==BMS-1 );
- if( pOrderBy && pOrderBy->nExpr>=BMS ) pOrderBy = 0;
+ if( pOrderBy && pOrderBy->nExpr>=BMS ){
+ pOrderBy = 0;
+ wctrlFlags &= ~WHERE_WANT_DISTINCT;
+ }
/* The number of tables in the FROM clause is limited by the number of
** bits in a Bitmask
@@ -5933,7 +6087,10 @@ WhereInfo *sqlite3WhereBegin(
** field (type Bitmask) it must be aligned on an 8-byte boundary on
** some architectures. Hence the ROUND8() below.
*/
- nByteWInfo = ROUND8P(sizeof(WhereInfo)+(nTabList-1)*sizeof(WhereLevel));
+ nByteWInfo = ROUND8P(sizeof(WhereInfo));
+ if( nTabList>1 ){
+ nByteWInfo = ROUND8P(nByteWInfo + (nTabList-1)*sizeof(WhereLevel));
+ }
pWInfo = sqlite3DbMallocRawNN(db, nByteWInfo + sizeof(WhereLoop));
if( db->mallocFailed ){
sqlite3DbFree(db, pWInfo);
@@ -6143,6 +6300,16 @@ WhereInfo *sqlite3WhereBegin(
wherePathSolver(pWInfo, pWInfo->nRowOut+1);
if( db->mallocFailed ) goto whereBeginError;
}
+
+ /* TUNING: Assume that a DISTINCT clause on a subquery reduces
+ ** the output size by a factor of 8 (LogEst -30).
+ */
+ if( (pWInfo->wctrlFlags & WHERE_WANT_DISTINCT)!=0 ){
+ WHERETRACE(0x0080,("nRowOut reduced from %d to %d due to DISTINCT\n",
+ pWInfo->nRowOut, pWInfo->nRowOut-30));
+ pWInfo->nRowOut -= 30;
+ }
+
}
assert( pWInfo->pTabList!=0 );
if( pWInfo->pOrderBy==0 && (db->flags & SQLITE_ReverseOrder)!=0 ){
@@ -6355,6 +6522,11 @@ WhereInfo *sqlite3WhereBegin(
if( pIx->bHasExpr && OptimizationEnabled(db, SQLITE_IndexedExpr) ){
whereAddIndexedExpr(pParse, pIx, iIndexCur, pTabItem);
}
+ if( pIx->pPartIdxWhere && (pTabItem->fg.jointype & JT_RIGHT)==0 ){
+ wherePartIdxExpr(
+ pParse, pIx, pIx->pPartIdxWhere, 0, iIndexCur, pTabItem
+ );
+ }
}
pLevel->iIdxCur = iIndexCur;
assert( pIx!=0 );
@@ -6480,6 +6652,11 @@ whereBeginError:
pParse->nQueryLoop = pWInfo->savedNQueryLoop;
whereInfoFree(db, pWInfo);
}
+#ifdef WHERETRACE_ENABLED
+ /* Prevent harmless compiler warnings about debugging routines
+ ** being declared but never used */
+ sqlite3ShowWhereLoopList(0);
+#endif /* WHERETRACE_ENABLED */
return 0;
}