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High-speed version of NGQP. Still has some minor problems.

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FossilOrigin-Name: db2415fa677b84cd0f6dd424283c94e98d246e3b
This commit is contained in:
drh
2013-06-09 17:21:25 +00:00
parent 23fec451a6
commit 60c96cd789
3 changed files with 105 additions and 29 deletions
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117
src/where.c
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@@ -5168,6 +5168,75 @@ static int wherePathSolver(WhereInfo *pWInfo, WhereCost nRowEst){
return SQLITE_OK;
}
/*
** Most queries use only a single table (they are not joins) and have
** simple == constraints against indexed fields. This routine attempts
** to plan those simple cases using much less ceremony than the
** general-purpose query planner, and thereby yield faster sqlite3_prepare()
** times for the common case.
**
** Return non-zero on success, if this query can be handled by this
** no-frills query planner. Return zero if this query needs the
** general-purpose query planner.
*/
static int whereSimpleFastCase(WhereLoopBuilder *pBuilder){
WhereInfo *pWInfo;
struct SrcList_item *pItem;
WhereClause *pWC;
WhereTerm *pTerm;
WhereLoop *pLoop;
int iCur;
int i, j;
int nOrderBy;
Table *pTab;
Index *pIdx;
pWInfo = pBuilder->pWInfo;
assert( pWInfo->pTabList->nSrc>=1 );
pItem = pWInfo->pTabList->a;
pTab = pItem->pTab;
if( IsVirtual(pTab) ) return 0;
if( pItem->zIndex ) return 0;
iCur = pItem->iCursor;
pWC = &pWInfo->sWC;
pLoop = pBuilder->pNew;
pWInfo->a[0].pWLoop = pLoop;
pLoop->wsFlags = 0;
nOrderBy = pWInfo->pOrderBy ? pWInfo->pOrderBy->nExpr : 0;
pTerm = findTerm(pWC, iCur, -1, 1, WO_EQ, 0);
if( pTerm ){
pLoop->wsFlags = WHERE_COLUMN_EQ|WHERE_IPK|WHERE_ONEROW;
pLoop->aLTerm[0] = pTerm;
pLoop->nLTerm = 1;
pLoop->u.btree.nEq = 1;
pLoop->rRun = (WhereCost)10;
pLoop->nOut = (WhereCost)1;
pWInfo->nRowOut = 1;
pWInfo->nOBSat = nOrderBy;
}else{
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_None ) continue;
for(j=0; j<pIdx->nColumn; j++){
pTerm = findTerm(pWC, iCur, pIdx->aiColumn[j], 1, WO_EQ, pIdx);
if( pTerm==0 ) break;
whereLoopResize(pWInfo->pParse->db, pLoop, j);
pLoop->aLTerm[j] = pTerm;
}
if( j!=pIdx->nColumn ) continue;
pLoop->wsFlags = WHERE_COLUMN_EQ|WHERE_ONEROW;
pLoop->nLTerm = j;
pLoop->u.btree.nEq = j;
pLoop->u.btree.pIndex = pIdx;
pLoop->rRun = (WhereCost)15;
pLoop->nOut = (WhereCost)1;
pWInfo->nRowOut = 1;
pWInfo->nOBSat = nOrderBy;
break;
}
}
return pLoop->wsFlags!=0;
}
/*
** Generate the beginning of the loop used for WHERE clause processing.
** The return value is a pointer to an opaque structure that contains
@@ -5307,7 +5376,7 @@ WhereInfo *sqlite3WhereBegin(
*/
db = pParse->db;
nByteWInfo = ROUND8(sizeof(WhereInfo)+(nTabList-1)*sizeof(WhereLevel));
pWInfo = sqlite3DbMallocZero(db, nByteWInfo);
pWInfo = sqlite3DbMallocZero(db, nByteWInfo + sizeof(WhereLoop));
if( db->mallocFailed ){
sqlite3DbFree(db, pWInfo);
pWInfo = 0;
@@ -5324,6 +5393,8 @@ WhereInfo *sqlite3WhereBegin(
pMaskSet = &pWInfo->sMaskSet;
sWLB.pWInfo = pWInfo;
sWLB.pWC = &pWInfo->sWC;
sWLB.pNew = (WhereLoop*)&pWInfo->a[nTabList];
whereLoopInit(sWLB.pNew);
/* Disable the DISTINCT optimization if SQLITE_DistinctOpt is set via
** sqlite3_test_ctrl(SQLITE_TESTCTRL_OPTIMIZATIONS,...) */
@@ -5396,30 +5467,32 @@ WhereInfo *sqlite3WhereBegin(
/* Construct the WhereLoop objects */
WHERETRACE(("*** Optimizer Start ***\n"));
/* TBD: if( nTablist==1 ) whereCommonCase(&sWLB); */
rc = whereLoopAddAll(&sWLB);
if( rc ) goto whereBeginError;
/* Display all of the WhereLoop objects if wheretrace is enabled */
if( nTabList!=1 || whereSimpleFastCase(&sWLB)==0 ){
rc = whereLoopAddAll(&sWLB);
if( rc ) goto whereBeginError;
/* Display all of the WhereLoop objects if wheretrace is enabled */
#ifdef WHERETRACE_ENABLED
if( sqlite3WhereTrace ){
WhereLoop *p;
int i = 0;
static char zLabel[] = "0123456789abcdefghijklmnopqrstuvwyxz"
"ABCDEFGHIJKLMNOPQRSTUVWYXZ";
for(p=pWInfo->pLoops; p; p=p->pNextLoop){
p->cId = zLabel[(i++)%sizeof(zLabel)];
whereLoopPrint(p, pTabList);
if( sqlite3WhereTrace ){
WhereLoop *p;
int i = 0;
static char zLabel[] = "0123456789abcdefghijklmnopqrstuvwyxz"
"ABCDEFGHIJKLMNOPQRSTUVWYXZ";
for(p=pWInfo->pLoops; p; p=p->pNextLoop){
p->cId = zLabel[(i++)%sizeof(zLabel)];
whereLoopPrint(p, pTabList);
}
}
#endif
wherePathSolver(pWInfo, -1);
if( db->mallocFailed ) goto whereBeginError;
if( pWInfo->pOrderBy ){
wherePathSolver(pWInfo, pWInfo->nRowOut);
if( db->mallocFailed ) goto whereBeginError;
}
}
#endif
wherePathSolver(pWInfo, -1);
if( db->mallocFailed ) goto whereBeginError;
if( pWInfo->pOrderBy ){
wherePathSolver(pWInfo, pWInfo->nRowOut);
if( db->mallocFailed ) goto whereBeginError;
}else if( db->flags & SQLITE_ReverseOrder ){
if( pWInfo->pOrderBy==0 && (db->flags & SQLITE_ReverseOrder)!=0 ){
pWInfo->revMask = (Bitmask)(-1);
}
if( pParse->nErr || db->mallocFailed ){