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Fix some issues with INSTEAD OF triggers. (CVS 930)

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FossilOrigin-Name: 206b17397b1d2b55179c935927ff1d8215728c32
This commit is contained in:
drh
2003-04-24 01:45:04 +00:00
parent b5a20d3ceb
commit 5cf590c128
17 changed files with 381 additions and 369 deletions
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155
src/trigger.c
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@@ -41,7 +41,7 @@ void sqliteDeleteTriggerStep(TriggerStep *pTriggerStep){
void sqliteBeginTrigger(
Parse *pParse, /* The parse context of the CREATE TRIGGER statement */
Token *pName, /* The name of the trigger */
int tr_tm, /* One of TK_BEFORE, TK_AFTER , TK_INSTEAD */
int tr_tm, /* One of TK_BEFORE, TK_AFTER, TK_INSTEAD */
int op, /* One of TK_INSERT, TK_UPDATE, TK_DELETE */
IdList *pColumns, /* column list if this is an UPDATE OF trigger */
SrcList *pTableName,/* The name of the table/view the trigger applies to */
@@ -110,6 +110,11 @@ void sqliteBeginTrigger(
}
#endif
/* INSTEAD OF triggers can only appear on views and BEGIN triggers
** cannot appear on views. So we might as well translate every
** INSTEAD OF trigger into a BEFORE trigger. It simplifies code
** elsewhere.
*/
if (tr_tm == TK_INSTEAD){
tr_tm = TK_BEFORE;
}
@@ -627,7 +632,7 @@ int sqliteCodeRowTrigger(
TriggerStack * pTriggerStack;
assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
assert(tr_tm == TK_BEFORE || tr_tm == TK_AFTER);
assert(tr_tm == TK_BEFORE || tr_tm == TK_AFTER );
assert(newIdx != -1 || oldIdx != -1);
@@ -656,6 +661,7 @@ int sqliteCodeRowTrigger(
int endTrigger;
SrcList dummyTablist;
Expr * whenExpr;
const char *zSavedAuthContext;
dummyTablist.nSrc = 0;
@@ -667,6 +673,8 @@ int sqliteCodeRowTrigger(
pTriggerStack->pNext = pParse->trigStack;
pTriggerStack->ignoreJump = ignoreJump;
pParse->trigStack = pTriggerStack;
zSavedAuthContext = pParse->zAuthContext;
pParse->zAuthContext = pTrigger->name;
/* code the WHEN clause */
endTrigger = sqliteVdbeMakeLabel(pParse->pVdbe);
@@ -684,6 +692,7 @@ int sqliteCodeRowTrigger(
/* Pop the entry off the trigger stack */
pParse->trigStack = pParse->trigStack->pNext;
pParse->zAuthContext = zSavedAuthContext;
sqliteFree(pTriggerStack);
sqliteVdbeResolveLabel(pParse->pVdbe, endTrigger);
@@ -693,145 +702,3 @@ int sqliteCodeRowTrigger(
return 0;
}
/*
* This function is called to code ON UPDATE and ON DELETE triggers on
* views.
*
* This function deletes the data pointed at by the pWhere and pChanges
* arguments before it completes.
*/
void sqliteViewTriggers(
Parse *pParse,
Table *pTab, /* The view to code triggers on */
Expr *pWhere, /* The WHERE clause of the statement causing triggers*/
int orconf, /* The ON CONFLICT policy specified as part of the
statement causing these triggers */
ExprList *pChanges /* If this is an statement causing triggers to fire
is an UPDATE, then this list holds the columns
to update and the expressions to update them to.
See comments for sqliteUpdate(). */
){
int oldIdx = -1;
int newIdx = -1;
int *aXRef = 0;
Vdbe *v;
int endOfLoop;
int startOfLoop;
Select theSelect;
Token tblNameToken;
assert(pTab->pSelect);
tblNameToken.z = pTab->zName;
tblNameToken.n = strlen(pTab->zName);
theSelect.isDistinct = 0;
theSelect.pEList = sqliteExprListAppend(0, sqliteExpr(TK_ALL, 0, 0, 0), 0);
theSelect.pSrc = sqliteSrcListAppend(0, &tblNameToken, 0);
theSelect.pWhere = pWhere; pWhere = 0;
theSelect.pGroupBy = 0;
theSelect.pHaving = 0;
theSelect.pOrderBy = 0;
theSelect.op = TK_SELECT; /* ?? */
theSelect.pPrior = 0;
theSelect.nLimit = -1;
theSelect.nOffset = -1;
theSelect.zSelect = 0;
theSelect.base = 0;
v = sqliteGetVdbe(pParse);
assert(v);
sqliteBeginWriteOperation(pParse, 1, 0);
/* Allocate temp tables */
oldIdx = pParse->nTab++;
sqliteVdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
if( pChanges ){
newIdx = pParse->nTab++;
sqliteVdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
}
/* Snapshot the view */
if( sqliteSelect(pParse, &theSelect, SRT_Table, oldIdx, 0, 0, 0) ){
goto trigger_cleanup;
}
/* loop thru the view snapshot, executing triggers for each row */
endOfLoop = sqliteVdbeMakeLabel(v);
sqliteVdbeAddOp(v, OP_Rewind, oldIdx, endOfLoop);
/* Loop thru the view snapshot, executing triggers for each row */
startOfLoop = sqliteVdbeCurrentAddr(v);
/* Build the updated row if required */
if( pChanges ){
int ii;
aXRef = sqliteMalloc( sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto trigger_cleanup;
for(ii = 0; ii < pTab->nCol; ii++){
aXRef[ii] = -1;
}
for(ii=0; ii<pChanges->nExpr; ii++){
int jj;
if( sqliteExprResolveIds(pParse, oldIdx, theSelect.pSrc , 0,
pChanges->a[ii].pExpr) ){
goto trigger_cleanup;
}
if( sqliteExprCheck(pParse, pChanges->a[ii].pExpr, 0, 0) )
goto trigger_cleanup;
for(jj=0; jj<pTab->nCol; jj++){
if( sqliteStrICmp(pTab->aCol[jj].zName, pChanges->a[ii].zName)==0 ){
aXRef[jj] = ii;
break;
}
}
if( jj>=pTab->nCol ){
sqliteErrorMsg(pParse, "no such column: %s", pChanges->a[ii].zName);
goto trigger_cleanup;
}
}
sqliteVdbeAddOp(v, OP_Integer, 13, 0);
for(ii = 0; ii<pTab->nCol; ii++){
if( aXRef[ii] < 0 ){
sqliteVdbeAddOp(v, OP_Column, oldIdx, ii);
}else{
sqliteExprCode(pParse, pChanges->a[aXRef[ii]].pExpr);
}
}
sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);
sqliteVdbeAddOp(v, OP_Rewind, newIdx, 0);
sqliteCodeRowTrigger(pParse, TK_UPDATE, pChanges, TK_BEFORE,
pTab, newIdx, oldIdx, orconf, endOfLoop);
sqliteCodeRowTrigger(pParse, TK_UPDATE, pChanges, TK_AFTER,
pTab, newIdx, oldIdx, orconf, endOfLoop);
}else{
sqliteCodeRowTrigger(pParse, TK_DELETE, 0, TK_BEFORE, pTab, -1, oldIdx,
orconf, endOfLoop);
sqliteCodeRowTrigger(pParse, TK_DELETE, 0, TK_AFTER, pTab, -1, oldIdx,
orconf, endOfLoop);
}
sqliteVdbeAddOp(v, OP_Next, oldIdx, startOfLoop);
sqliteVdbeResolveLabel(v, endOfLoop);
sqliteEndWriteOperation(pParse);
trigger_cleanup:
sqliteFree(aXRef);
sqliteExprListDelete(pChanges);
sqliteExprDelete(pWhere);
sqliteExprListDelete(theSelect.pEList);
sqliteSrcListDelete(theSelect.pSrc);
sqliteExprDelete(theSelect.pWhere);
return;
}