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Now generating OR-clause plans.

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FossilOrigin-Name: e17003fcfec0c0b524b1b9ff8e15e7ee83efa571
This commit is contained in:
drh
2013-05-10 20:26:22 +00:00
parent eb04de3224
commit cf8fa7a65b
3 changed files with 116 additions and 19 deletions
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121
src/where.c
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@@ -289,6 +289,7 @@ struct WhereLoopBuilder {
SrcList *pTabList; /* FROM clause */
ExprList *pOrderBy; /* ORDER BY clause */
WhereLoop *pNew; /* Template WhereLoop */
WhereLoop *pBest; /* If non-NULL, store single best loop here */
int mxTerm; /* Maximum number of aTerm[] entries on pNew */
};
@@ -5162,10 +5163,27 @@ static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
** fewer dependencies than the template. Otherwise a new WhereLoop is
** added based no the template.
*/
static int whereLoopInsert(WhereInfo *pWInfo, WhereLoop *pTemplate){
static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
WhereLoop **ppPrev, *p, *pNext = 0, *pToFree = 0;
WhereTerm **paTerm = 0;
sqlite3 *db = pWInfo->pParse->db;
sqlite3 *db = pBuilder->db;
WhereInfo *pWInfo = pBuilder->pWInfo;
if( (p = pBuilder->pBest)!=0 ){
if( p->maskSelf!=0 ){
if( p->rRun+p->rSetup < pTemplate->rRun+pTemplate->rSetup ){
return SQLITE_OK;
}
if( p->rRun+p->rSetup == pTemplate->rRun+pTemplate->rSetup
&& p->prereq <= pTemplate->prereq ){
return SQLITE_OK;
}
}
*p = *pTemplate;
p->aTerm = 0;
p->u.vtab.needFree = 0;
return SQLITE_OK;
}
/* Search for an existing WhereLoop to overwrite, or which takes
** priority over pTemplate.
@@ -5210,11 +5228,13 @@ static int whereLoopInsert(WhereInfo *pWInfo, WhereLoop *pTemplate){
p->pNextLoop = pNext;
*ppPrev = p;
p->aTerm = paTerm;
if( pTemplate->nTerm ){
memcpy(p->aTerm, pTemplate->aTerm, pTemplate->nTerm*sizeof(p->aTerm[0]));
if( p->nTerm ){
memcpy(p->aTerm, pTemplate->aTerm, p->nTerm*sizeof(p->aTerm[0]));
}
if( (p->wsFlags & WHERE_VIRTUALTABLE)==0 ){
if( p->u.btree.pIndex && p->u.btree.pIndex->tnum==0 ) p->u.btree.pIndex = 0;
if( p->u.btree.pIndex && p->u.btree.pIndex->tnum==0 ){
p->u.btree.pIndex = 0;
}
}else{
pTemplate->u.vtab.needFree = 0;
}
@@ -5305,7 +5325,7 @@ static int whereLoopAddBtreeIndex(
}
/* TBD: Adjust nOut and rRun for STAT3 range values */
/* TBD: Adjust nOut for additional constraints */
rc = whereLoopInsert(pBuilder->pWInfo, pNew);
rc = whereLoopInsert(pBuilder, pNew);
if( (pNew->wsFlags & WHERE_TOP_LIMIT)==0
&& pNew->u.btree.nEq<pProbe->nColumn
){
@@ -5366,7 +5386,8 @@ static int whereLoopAddBtree(
rLogSize = estLog(rSize);
/* Automatic indexes */
if( (pBuilder->pParse->db->flags & SQLITE_AutoIndex)!=0
if( !pBuilder->pBest
&& (pBuilder->pParse->db->flags & SQLITE_AutoIndex)!=0
&& !pSrc->viaCoroutine
&& !pSrc->notIndexed
&& !pSrc->isCorrelated
@@ -5385,7 +5406,7 @@ static int whereLoopAddBtree(
pNew->rRun = rLogSize + pNew->nOut;
pNew->wsFlags = WHERE_TEMP_INDEX;
pNew->prereq = mExtra | pTerm->prereqRight;
rc = whereLoopInsert(pBuilder->pWInfo, pNew);
rc = whereLoopInsert(pBuilder, pNew);
}
}
}
@@ -5400,7 +5421,7 @@ static int whereLoopAddBtree(
pNew->nOut = rSize;
pNew->rRun = rSize + rLogSize;
/* TBD: Reduce nOut using constraints */
rc = whereLoopInsert(pBuilder->pWInfo, pNew);
rc = whereLoopInsert(pBuilder, pNew);
/* Loop over all indices
*/
@@ -5565,7 +5586,7 @@ static int whereLoopAddVirtual(
pNew->rSetup = (double)0;
pNew->rRun = pIdxInfo->estimatedCost;
pNew->nOut = (double)25;
whereLoopInsert(pBuilder->pWInfo, pNew);
whereLoopInsert(pBuilder, pNew);
if( pNew->u.vtab.needFree ){
sqlite3_free(pNew->u.vtab.idxStr);
pNew->u.vtab.needFree = 0;
@@ -5579,6 +5600,84 @@ whereLoopAddVtab_exit:
return rc;
}
/*
** Add WhereLoop entries to handle OR terms. This works for either
** btrees or virtual tables.
*/
static int whereLoopAddOr(WhereLoopBuilder *pBuilder, Bitmask mExtra){
WhereClause *pWC;
WhereLoop *pNew;
WhereTerm *pTerm, *pWCEnd;
int rc = SQLITE_OK;
int iCur;
WhereClause tempWC;
WhereLoopBuilder sSubBuild;
WhereLoop sBest;
struct SrcList_item *pItem;
pWC = pBuilder->pWC;
if( pWC->wctrlFlags & WHERE_AND_ONLY ) return SQLITE_OK;
pWCEnd = pWC->a + pWC->nTerm;
pNew = pBuilder->pNew;
pItem = pBuilder->pTabList->a + pNew->iTab;
iCur = pItem->iCursor;
sSubBuild = *pBuilder;
sSubBuild.pOrderBy = 0;
sSubBuild.pBest = &sBest;
tempWC.pParse = pWC->pParse;
tempWC.pMaskSet = pWC->pMaskSet;
tempWC.pOuter = pWC;
tempWC.op = TK_AND;
tempWC.wctrlFlags = 0;
tempWC.nTerm = 1;
for(pTerm=pWC->a; pTerm<pWCEnd && rc==SQLITE_OK; pTerm++){
if( (pTerm->eOperator & WO_OR)!=0
&& (pTerm->u.pOrInfo->indexable & pNew->maskSelf)!=0
){
WhereClause * const pOrWC = &pTerm->u.pOrInfo->wc;
WhereTerm * const pOrWCEnd = &pOrWC->a[pOrWC->nTerm];
WhereTerm *pOrTerm;
double rTotal = 0;
double nRow = 0;
Bitmask prereq = mExtra;
for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){
if( (pOrTerm->eOperator& WO_AND)!=0 ){
sSubBuild.pWC = &pOrTerm->u.pAndInfo->wc;
}else if( pOrTerm->leftCursor==iCur ){
tempWC.a = pOrTerm;
sSubBuild.pWC = &tempWC;
}else{
continue;
}
sBest.maskSelf = 0;
if( IsVirtual(pItem->pTab) ){
rc = whereLoopAddVirtual(&sSubBuild, mExtra);
}else{
rc = whereLoopAddBtree(&sSubBuild, mExtra);
}
if( sBest.maskSelf==0 ) break;
assert( sBest.rSetup==(double)0 );
rTotal += sBest.rRun;
nRow += sBest.nOut;
prereq |= sBest.prereq;
}
pNew->nTerm = 1;
pNew->aTerm[0] = pTerm;
pNew->wsFlags = WHERE_MULTI_OR;
pNew->rSetup = (double)0;
pNew->rRun = rTotal;
pNew->nOut = nRow;
pNew->prereq = prereq;
rc = whereLoopInsert(pBuilder, pNew);
}
}
return rc;
}
/*
** Add all WhereLoop objects for all tables
*/
@@ -5619,11 +5718,9 @@ static int whereLoopAddAll(WhereLoopBuilder *pBuilder){
}else{
rc = whereLoopAddBtree(pBuilder, mExtra);
}
#if 0
if( rc==SQLITE_OK ){
rc = whereLoopAddOr(pBuilder, mExtra);
}
#endif
mPrior |= pNew->maskSelf;
if( rc || db->mallocFailed ) break;
}