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Handle virtual tables correctly when using logarithmic costs. Fixes

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to test cases.

FossilOrigin-Name: e612664aa2e24ed5e222be2c7fe16e210ac9bded
This commit is contained in:
drh
2013-06-11 01:50:08 +00:00
parent 5822d6feb2
commit 8636e9c55c
6 changed files with 64 additions and 35 deletions
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39
src/where.c
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@@ -1882,6 +1882,23 @@ static WhereCost whereCostFromInt(tRowcnt x){
return a[x&7] + y - 10;
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Convert a double (as received from xBestIndex of a virtual table)
** into a WhereCost
*/
static WhereCost whereCostFromDouble(double x){
u64 a;
WhereCost e;
assert( sizeof(x)==8 && sizeof(a)==8 );
if( x<=1 ) return 0;
if( x<=2000000000 ) return whereCostFromInt((tRowcnt)x);
memcpy(&a, &x, 8);
e = (a>>52) - 1022;
return e*10;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
/*
** Prepare a crude estimate of the logarithm of the input value.
** The results need not be exact. This is only used for estimating
@@ -4088,6 +4105,14 @@ static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
** more terms of the index */
pNext = p->pNextLoop;
break;
}else if( p->nOut>pTemplate->nOut
&& p->rSetup==pTemplate->rSetup
&& p->rRun==pTemplate->rRun
){
/* Overwrite an existing WhereLoop with the same cost but more
** outputs */
pNext = p->pNextLoop;
break;
}else{
/* pTemplate is not helpful.
** Return without changing or adding anything */
@@ -4263,7 +4288,7 @@ static int whereLoopAddBtreeIndex(
WhereCost rDiv;
whereRangeScanEst(pParse, pProbe, pNew->u.btree.nEq,
pBtm, pTop, &rDiv);
pNew->nOut = saved_nOut - rDiv;
pNew->nOut = saved_nOut>rDiv+10 ? saved_nOut - rDiv : 10;
}
#ifdef SQLITE_ENABLE_STAT3
if( pNew->u.btree.nEq==1 && pProbe->nSample ){
@@ -4482,6 +4507,7 @@ static int whereLoopAddBtree(
return rc;
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Add all WhereLoop objects for a table of the join identified by
** pBuilder->pNew->iTab. That table is guaranteed to be a virtual table.
@@ -4569,8 +4595,7 @@ static int whereLoopAddVirtual(
pIdxInfo->idxNum = 0;
pIdxInfo->needToFreeIdxStr = 0;
pIdxInfo->orderByConsumed = 0;
/* ((WhereCost)2) In case of SQLITE_OMIT_FLOATING_POINT... */
pIdxInfo->estimatedCost = SQLITE_BIG_DBL / ((WhereCost)2);
pIdxInfo->estimatedCost = SQLITE_BIG_DBL / (double)2;
rc = vtabBestIndex(pParse, pTab, pIdxInfo);
if( rc ) goto whereLoopAddVtab_exit;
pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
@@ -4624,7 +4649,7 @@ static int whereLoopAddVirtual(
pNew->u.vtab.isOrdered = (u8)((pIdxInfo->nOrderBy!=0)
&& pIdxInfo->orderByConsumed);
pNew->rSetup = 0;
pNew->rRun = whereCostFromInt((tRowcnt)pIdxInfo->estimatedCost);
pNew->rRun = whereCostFromDouble(pIdxInfo->estimatedCost);
pNew->nOut = 46; assert( 46 == whereCostFromInt(25) );
whereLoopInsert(pBuilder, pNew);
if( pNew->u.vtab.needFree ){
@@ -4639,6 +4664,7 @@ whereLoopAddVtab_exit:
sqlite3DbFree(db, pIdxInfo);
return rc;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
/*
** Add WhereLoop entries to handle OR terms. This works for either
@@ -4695,9 +4721,12 @@ static int whereLoopAddOr(WhereLoopBuilder *pBuilder, Bitmask mExtra){
sBest.maskSelf = 0;
sBest.rSetup = 0;
sBest.rRun = 0;
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pItem->pTab) ){
rc = whereLoopAddVirtual(&sSubBuild, mExtra);
}else{
}else
#endif
{
rc = whereLoopAddBtree(&sSubBuild, mExtra);
}
if( sBest.maskSelf==0 ) break;