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Run as many Bloom filters as possible before index lookups.

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FossilOrigin-Name: 06f6fefd67086896bc49272c6319545ff6c6792f18babe23aced27b60b032119
This commit is contained in:
drh
2021-12-05 20:19:47 +00:00
parent 35685d3e5e
commit 6ae49e67cc
6 changed files with 158 additions and 76 deletions
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129
src/where.c
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@@ -966,61 +966,92 @@ end_auto_index_create:
#endif /* SQLITE_OMIT_AUTOMATIC_INDEX */
/*
** Create a Bloom filter for the WhereLevel in the parameter.
** Generate bytecode that will initialize a Bloom filter that is appropriate
** for pLevel.
**
** If there are inner loops within pLevel that have the WHERE_BLOOMFILTER
** flag set, initialize a Bloomfilter for them as well. Except don't do
** this recursive initialization if the SQLITE_BloomPulldown optimization has
** been turned off.
**
** When the Bloom filter is initialized, the WHERE_BLOOMFILTER flag is cleared
** from the loop, but the regFilter value is set to a register that implements
** the Bloom filter. When regFilter is positive, the
** sqlite3WhereCodeOneLoopStart() will generate code to test the Bloom filter
** and skip the subsequence B-Tree seek if the Bloom filter indicates that
** no matching rows exist.
**
** This routine may only be called if it has previously been determined that
** the loop would benefit from a Bloom filter, and the WHERE_BLOOMFILTER bit
** is set.
*/
SQLITE_NOINLINE void sqlite3ConstructBloomFilter(
const WhereInfo *pWInfo, /* The WHERE clause */
WhereLevel *pLevel /* Make a Bloom filter for this FROM term */
static SQLITE_NOINLINE void constructBloomFilter(
WhereInfo *pWInfo, /* The WHERE clause */
int iLevel, /* Index in pWInfo->a[] that is pLevel */
WhereLevel *pLevel /* Make a Bloom filter for this FROM term */
){
int addrTop;
int addrCont;
const WhereTerm *pTerm;
const WhereTerm *pWCEnd;
Parse *pParse = pWInfo->pParse;
Vdbe *v = pParse->pVdbe;
const WhereLoop *pLoop = pLevel->pWLoop;
int iCur;
int addrOnce; /* Address of opening OP_Once */
int addrTop; /* Address of OP_Rewind */
int addrCont; /* Jump here to skip a row */
const WhereTerm *pTerm; /* For looping over WHERE clause terms */
const WhereTerm *pWCEnd; /* Last WHERE clause term */
Parse *pParse = pWInfo->pParse; /* Parsing context */
Vdbe *v = pParse->pVdbe; /* VDBE under construction */
WhereLoop *pLoop = pLevel->pWLoop; /* The loop being coded */
int iCur; /* Cursor for table getting the filter */
assert( pLoop!=0 );
assert( v!=0 );
iCur = pLevel->iTabCur;
addrCont = sqlite3VdbeMakeLabel(pParse);
addrTop = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
pLevel->regFilter = ++pParse->nMem;
sqlite3VdbeAddOp1(v, OP_FilterInit, pLevel->regFilter);
sqlite3VdbeAddOp1(v, OP_Rewind, iCur); VdbeCoverage(v);
pWCEnd = &pWInfo->sWC.a[pWInfo->sWC.nTerm];
for(pTerm=pWInfo->sWC.a; pTerm<pWCEnd; pTerm++){
Expr *pExpr = pTerm->pExpr;
if( (pTerm->wtFlags & TERM_VIRTUAL)==0
&& sqlite3ExprIsTableConstant(pExpr, iCur)
){
sqlite3ExprIfFalse(pParse, pTerm->pExpr, addrCont, SQLITE_JUMPIFNULL);
assert( pLoop->wsFlags & WHERE_BLOOMFILTER );
addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
do{
sqlite3WhereExplainBloomFilter(pParse, pWInfo, pLevel);
addrCont = sqlite3VdbeMakeLabel(pParse);
iCur = pLevel->iTabCur;
pLevel->regFilter = ++pParse->nMem;
sqlite3VdbeAddOp1(v, OP_FilterInit, pLevel->regFilter);
addrTop = sqlite3VdbeAddOp1(v, OP_Rewind, iCur); VdbeCoverage(v);
pWCEnd = &pWInfo->sWC.a[pWInfo->sWC.nTerm];
for(pTerm=pWInfo->sWC.a; pTerm<pWCEnd; pTerm++){
Expr *pExpr = pTerm->pExpr;
if( (pTerm->wtFlags & TERM_VIRTUAL)==0
&& sqlite3ExprIsTableConstant(pExpr, iCur)
){
sqlite3ExprIfFalse(pParse, pTerm->pExpr, addrCont, SQLITE_JUMPIFNULL);
}
}
}
if( pLoop->wsFlags & WHERE_IPK ){
int r1 = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, r1);
sqlite3VdbeAddOp4Int(v, OP_FilterAdd, pLevel->regFilter, 0, r1, 1);
sqlite3ReleaseTempReg(pParse, r1);
}else{
Index *pIdx = pLoop->u.btree.pIndex;
int n = pLoop->u.btree.nEq;
int r1 = sqlite3GetTempRange(pParse, n);
int jj;
for(jj=0; jj<n; jj++){
int iCol = pIdx->aiColumn[jj];
sqlite3ExprCodeGetColumnOfTable(v, pIdx->pTable, iCur, iCol,r1+jj);
if( pLoop->wsFlags & WHERE_IPK ){
int r1 = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, r1);
sqlite3VdbeAddOp4Int(v, OP_FilterAdd, pLevel->regFilter, 0, r1, 1);
sqlite3ReleaseTempReg(pParse, r1);
}else{
Index *pIdx = pLoop->u.btree.pIndex;
int n = pLoop->u.btree.nEq;
int r1 = sqlite3GetTempRange(pParse, n);
int jj;
for(jj=0; jj<n; jj++){
int iCol = pIdx->aiColumn[jj];
sqlite3ExprCodeGetColumnOfTable(v, pIdx->pTable, iCur, iCol,r1+jj);
}
sqlite3VdbeAddOp4Int(v, OP_FilterAdd, pLevel->regFilter, 0, r1, n);
sqlite3ReleaseTempRange(pParse, r1, n);
}
sqlite3VdbeAddOp4Int(v, OP_FilterAdd, pLevel->regFilter, 0, r1, n);
sqlite3ReleaseTempRange(pParse, r1, n);
}
sqlite3VdbeResolveLabel(v, addrCont);
sqlite3VdbeAddOp2(v, OP_Next, pLevel->iTabCur, addrTop+3);
VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addrTop);
sqlite3VdbeJumpHere(v, addrTop+2);
sqlite3VdbeResolveLabel(v, addrCont);
sqlite3VdbeAddOp2(v, OP_Next, pLevel->iTabCur, addrTop+1);
VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addrTop);
pLoop->wsFlags &= ~WHERE_BLOOMFILTER;
if( OptimizationDisabled(pParse->db, SQLITE_BloomPulldown) ) break;
while( iLevel < pWInfo->nLevel ){
iLevel++;
pLevel = &pWInfo->a[iLevel];
pLoop = pLevel->pWLoop;
if( pLoop && pLoop->wsFlags & WHERE_BLOOMFILTER ) break;
}
}while( iLevel < pWInfo->nLevel );
sqlite3VdbeJumpHere(v, addrOnce);
}
@@ -5535,7 +5566,7 @@ WhereInfo *sqlite3WhereBegin(
&pTabList->a[pLevel->iFrom], notReady, pLevel);
#endif
}else{
sqlite3ConstructBloomFilter(pWInfo, pLevel);
constructBloomFilter(pWInfo, ii, pLevel);
}
if( db->mallocFailed ) goto whereBeginError;
}