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Use symbolic names ONEPASS_OFF, ONEPASS_SINGLE, and ONEPASS_MULTI for the

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various modes of the one-pass optimization.

FossilOrigin-Name: 16e56bdadef903c6439a487f2683388aeeb0c625
This commit is contained in:
drh
2015-09-14 14:45:50 +00:00
parent 66336f3755
commit b0264eeca1
8 changed files with 55 additions and 47 deletions
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25
src/where.c
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@@ -69,9 +69,11 @@ int sqlite3WhereBreakLabel(WhereInfo *pWInfo){
}
/*
** Return TRUE if an UPDATE or DELETE statement can operate directly on
** the rowids returned by a WHERE clause. Return FALSE if doing an
** UPDATE or DELETE might change subsequent WHERE clause results.
** Return ONEPASS_OFF (0) if an UPDATE or DELETE statement is unable to
** operate directly on the rowis returned by a WHERE clause. Return
** ONEPASS_SINGLE (1) if the statement can operation directly because only
** a single row is to be changed. Return ONEPASS_MULTI (2) if the one-pass
** optimization can be used on multiple
**
** If the ONEPASS optimization is used (if this routine returns true)
** then also write the indices of open cursors used by ONEPASS
@@ -85,7 +87,7 @@ int sqlite3WhereBreakLabel(WhereInfo *pWInfo){
*/
int sqlite3WhereOkOnePass(WhereInfo *pWInfo, int *aiCur){
memcpy(aiCur, pWInfo->aiCurOnePass, sizeof(int)*2);
return pWInfo->okOnePass;
return pWInfo->eOnePass;
}
/*
@@ -4017,6 +4019,7 @@ WhereInfo *sqlite3WhereBegin(
pWInfo->iBreak = pWInfo->iContinue = sqlite3VdbeMakeLabel(v);
pWInfo->wctrlFlags = wctrlFlags;
pWInfo->savedNQueryLoop = pParse->nQueryLoop;
assert( pWInfo->eOnePass==ONEPASS_OFF ); /* ONEPASS defaults to OFF */
pMaskSet = &pWInfo->sMaskSet;
sWLB.pWInfo = pWInfo;
sWLB.pWC = &pWInfo->sWC;
@@ -4209,7 +4212,7 @@ WhereInfo *sqlite3WhereBegin(
if( bOnerow || ( (wctrlFlags & WHERE_ONEPASS_MULTIROW)
&& 0==(wsFlags & WHERE_VIRTUALTABLE)
)){
pWInfo->okOnePass = bOnerow ? 1 : 2;
pWInfo->eOnePass = bOnerow ? ONEPASS_SINGLE : ONEPASS_MULTI;
if( HasRowid(pTabList->a[0].pTab) ){
pWInfo->a[0].pWLoop->wsFlags &= ~WHERE_IDX_ONLY;
}
@@ -4243,15 +4246,15 @@ WhereInfo *sqlite3WhereBegin(
if( (pLoop->wsFlags & WHERE_IDX_ONLY)==0
&& (wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0 ){
int op = OP_OpenRead;
if( pWInfo->okOnePass ){
if( pWInfo->eOnePass!=ONEPASS_OFF ){
op = OP_OpenWrite;
pWInfo->aiCurOnePass[0] = pTabItem->iCursor;
};
sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, op);
assert( pTabItem->iCursor==pLevel->iTabCur );
testcase( !pWInfo->okOnePass && pTab->nCol==BMS-1 );
testcase( !pWInfo->okOnePass && pTab->nCol==BMS );
if( !pWInfo->okOnePass && pTab->nCol<BMS && HasRowid(pTab) ){
testcase( pWInfo->eOnePass==ONEPASS_OFF && pTab->nCol==BMS-1 );
testcase( pWInfo->eOnePass==ONEPASS_OFF && pTab->nCol==BMS );
if( pWInfo->eOnePass==ONEPASS_OFF && pTab->nCol<BMS && HasRowid(pTab) ){
Bitmask b = pTabItem->colUsed;
int n = 0;
for(; b; b=b>>1, n++){}
@@ -4279,7 +4282,7 @@ WhereInfo *sqlite3WhereBegin(
** WITHOUT ROWID table. No need for a separate index */
iIndexCur = pLevel->iTabCur;
op = 0;
}else if( pWInfo->okOnePass ){
}else if( pWInfo->eOnePass!=ONEPASS_OFF ){
Index *pJ = pTabItem->pTab->pIndex;
iIndexCur = iIdxCur;
assert( wctrlFlags & WHERE_ONEPASS_DESIRED );
@@ -4487,7 +4490,7 @@ void sqlite3WhereEnd(WhereInfo *pWInfo){
&& (pWInfo->wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0
){
int ws = pLoop->wsFlags;
if( !pWInfo->okOnePass && (ws & WHERE_IDX_ONLY)==0 ){
if( pWInfo->eOnePass==ONEPASS_OFF && (ws & WHERE_IDX_ONLY)==0 ){
sqlite3VdbeAddOp1(v, OP_Close, pTabItem->iCursor);
}
if( (ws & WHERE_INDEXED)!=0