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Merge latest begin-concurrent changes into this branch.

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FossilOrigin-Name: 6f3dd9809fdef7d6195f1f93428a662d5a8c01dba9815daa22d1b94059a2eb43
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dan
2018-09-28 21:11:12 +00:00
parent c1b7fdd43e 2dd93c8838
commit 0131a914d3
170 changed files with 12295 additions and 2577 deletions
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70
src/update.c
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@@ -79,6 +79,57 @@ void sqlite3ColumnDefault(Vdbe *v, Table *pTab, int i, int iReg){
#endif
}
/*
** Check to see if column iCol of index pIdx references any of the
** columns defined by aXRef and chngRowid. Return true if it does
** and false if not. This is an optimization. False-positives are a
** performance degradation, but false-negatives can result in a corrupt
** index and incorrect answers.
**
** aXRef[j] will be non-negative if column j of the original table is
** being updated. chngRowid will be true if the rowid of the table is
** being updated.
*/
static int indexColumnIsBeingUpdated(
Index *pIdx, /* The index to check */
int iCol, /* Which column of the index to check */
int *aXRef, /* aXRef[j]>=0 if column j is being updated */
int chngRowid /* true if the rowid is being updated */
){
i16 iIdxCol = pIdx->aiColumn[iCol];
assert( iIdxCol!=XN_ROWID ); /* Cannot index rowid */
if( iIdxCol>=0 ){
return aXRef[iIdxCol]>=0;
}
assert( iIdxCol==XN_EXPR );
assert( pIdx->aColExpr!=0 );
assert( pIdx->aColExpr->a[iCol].pExpr!=0 );
return sqlite3ExprReferencesUpdatedColumn(pIdx->aColExpr->a[iCol].pExpr,
aXRef,chngRowid);
}
/*
** Check to see if index pIdx is a partial index whose conditional
** expression might change values due to an UPDATE. Return true if
** the index is subject to change and false if the index is guaranteed
** to be unchanged. This is an optimization. False-positives are a
** performance degradation, but false-negatives can result in a corrupt
** index and incorrect answers.
**
** aXRef[j] will be non-negative if column j of the original table is
** being updated. chngRowid will be true if the rowid of the table is
** being updated.
*/
static int indexWhereClauseMightChange(
Index *pIdx, /* The index to check */
int *aXRef, /* aXRef[j]>=0 if column j is being updated */
int chngRowid /* true if the rowid is being updated */
){
if( pIdx->pPartIdxWhere==0 ) return 0;
return sqlite3ExprReferencesUpdatedColumn(pIdx->pPartIdxWhere,
aXRef, chngRowid);
}
/*
** Process an UPDATE statement.
**
@@ -313,19 +364,18 @@ void sqlite3Update(
/* There is one entry in the aRegIdx[] array for each index on the table
** being updated. Fill in aRegIdx[] with a register number that will hold
** the key for accessing each index.
**
** FIXME: Be smarter about omitting indexes that use expressions.
*/
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngKey || hasFK>1 || pIdx->pPartIdxWhere || pIdx==pPk ){
if( chngKey || hasFK>1 || pIdx==pPk
|| indexWhereClauseMightChange(pIdx,aXRef,chngRowid)
){
reg = ++pParse->nMem;
pParse->nMem += pIdx->nColumn;
}else{
reg = 0;
for(i=0; i<pIdx->nKeyCol; i++){
i16 iIdxCol = pIdx->aiColumn[i];
if( iIdxCol<0 || aXRef[iIdxCol]>=0 ){
if( indexColumnIsBeingUpdated(pIdx, i, aXRef, chngRowid) ){
reg = ++pParse->nMem;
pParse->nMem += pIdx->nColumn;
if( (onError==OE_Replace)
@@ -621,13 +671,7 @@ void sqlite3Update(
*/
testcase( i==31 );
testcase( i==32 );
sqlite3ExprCodeGetColumnToReg(pParse, pTab, i, iDataCur, regNew+i);
if( tmask & TRIGGER_BEFORE ){
/* This value will be recomputed in After-BEFORE-trigger-reload-loop
** below, so make sure that it is not cached and reused.
** Ticket d85fffd6ffe856092ed8daefa811b1e399706b28. */
sqlite3ExprCacheRemove(pParse, regNew+i, 1);
}
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regNew+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}
@@ -880,7 +924,7 @@ static void updateVirtualTable(
sqlite3ExprCode(pParse, pChanges->a[aXRef[i]].pExpr, regArg+2+i);
}else{
sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, i, regArg+2+i);
sqlite3VdbeChangeP5(v, 1); /* Enable sqlite3_vtab_nochange() */
sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG);/* Enable sqlite3_vtab_nochange() */
}
}
if( HasRowid(pTab) ){