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Take advantage of the fact that b-tree cursors need not be closed while other cursors modify their tables to simplify trigger program generation code. (CVS 4654)

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FossilOrigin-Name: f1966a8a47fca85f7862c0797a527ab01ac8b0c1
This commit is contained in:
danielk1977
2008-01-02 11:50:51 +00:00
parent eb9ae90137
commit e448dc4abf
7 changed files with 102 additions and 137 deletions
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131
src/update.c
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@@ -12,7 +12,7 @@
** This file contains C code routines that are called by the parser
** to handle UPDATE statements.
**
** $Id: update.c,v 1.146 2008/01/02 00:34:37 drh Exp $
** $Id: update.c,v 1.147 2008/01/02 11:50:51 danielk1977 Exp $
*/
#include "sqliteInt.h"
@@ -298,7 +298,16 @@ void sqlite3Update(
/* Generate the code for triggers.
*/
if( triggers_exist ){
int iGoto = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
int iGoto;
/* Create pseudo-tables for NEW and OLD
*/
sqlite3VdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, oldIdx, pTab->nCol);
sqlite3VdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, newIdx, pTab->nCol);
iGoto = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
addr = sqlite3VdbeMakeLabel(v);
iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_BEFORE, pTab,
@@ -347,27 +356,50 @@ void sqlite3Update(
sqlite3VdbeAddOp(v, OP_MemInt, 0, memCnt);
}
if( triggers_exist ){
/* Create pseudo-tables for NEW and OLD
if( !isView && !IsVirtual(pTab) ){
/*
** Open every index that needs updating. Note that if any
** index could potentially invoke a REPLACE conflict resolution
** action, then we need to open all indices because we might need
** to be deleting some records.
*/
sqlite3VdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, oldIdx, pTab->nCol);
sqlite3VdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, newIdx, pTab->nCol);
/* The top of the update loop for when there are triggers.
*/
sqlite3VdbeResolveLabel(v, addr);
addr = sqlite3VdbeAddOp(v, OP_FifoRead, 0, 0);
sqlite3VdbeAddOp(v, OP_StackDepth, -1, 0);
sqlite3VdbeAddOp(v, OP_MemStore, mem1, 0);
if( !isView ){
/* Open a cursor and make it point to the record that is
** being updated.
*/
sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
sqlite3VdbeOp3(v, OP_OpenWrite, iCur+i+1, pIdx->tnum,
(char*)pKey, P3_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
}
/* Jump back to this point if a trigger encounters an IGNORE constraint. */
if( triggers_exist ){
sqlite3VdbeResolveLabel(v, addr);
}
/* Top of the update loop */
addr = sqlite3VdbeAddOp(v, OP_FifoRead, 0, 0);
sqlite3VdbeAddOp(v, OP_StackDepth, -1, 0);
sqlite3VdbeAddOp(v, OP_MemStore, mem1, 0);
if( triggers_exist ){
/* Make cursor iCur point to the record that is being updated.
*/
sqlite3VdbeAddOp(v, OP_NotExists, iCur, addr);
/* Generate the OLD table
@@ -410,9 +442,6 @@ void sqlite3Update(
}
if( pParse->nErr ) goto update_cleanup;
sqlite3VdbeAddOp(v, OP_Insert, newIdx, 0);
if( !isView ){
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}
sqlite3VdbeAddOp(v, OP_Goto, 0, iBeginBeforeTrigger);
sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
@@ -423,33 +452,6 @@ void sqlite3Update(
}
if( !isView && !IsVirtual(pTab) ){
/*
** Open every index that needs updating. Note that if any
** index could potentially invoke a REPLACE conflict resolution
** action, then we need to open all indices because we might need
** to be deleting some records.
*/
sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
sqlite3VdbeOp3(v, OP_OpenWrite, iCur+i+1, pIdx->tnum,
(char*)pKey, P3_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
/* Loop over every record that needs updating. We have to load
** the old data for each record to be updated because some columns
@@ -457,11 +459,6 @@ void sqlite3Update(
** Also, the old data is needed to delete the old index entries.
** So make the cursor point at the old record.
*/
if( !triggers_exist ){
addr = sqlite3VdbeAddOp(v, OP_FifoRead, 0, 0);
sqlite3VdbeAddOp(v, OP_StackDepth, -1, 0);
sqlite3VdbeAddOp(v, OP_MemStore, mem1, 0);
}
sqlite3VdbeAddOp(v, OP_NotExists, iCur, addr);
sqlite3VdbeAddOp(v, OP_MemLoad, mem1, 0);
@@ -520,13 +517,6 @@ void sqlite3Update(
** through the loop. The fire the after triggers.
*/
if( triggers_exist ){
if( !isView ){
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] )
sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}
sqlite3VdbeAddOp(v, OP_Goto, 0, iBeginAfterTrigger);
sqlite3VdbeJumpHere(v, iEndAfterTrigger);
}
@@ -537,15 +527,14 @@ void sqlite3Update(
sqlite3VdbeAddOp(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
/* Close all tables if there were no FOR EACH ROW triggers */
if( !triggers_exist ){
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
/* Close all tables */
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}else{
}
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
if( triggers_exist ){
sqlite3VdbeAddOp(v, OP_Close, newIdx, 0);
sqlite3VdbeAddOp(v, OP_Close, oldIdx, 0);
}