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Finish registerizing the core logic of INSERT and UPDATE. (CVS 4696)

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FossilOrigin-Name: 5fd1036788dbbc48ff1c746d2e1ba12b04a7e58c
This commit is contained in:
drh
2008-01-08 18:57:50 +00:00
parent f858740ce9
commit 04adf4161d
6 changed files with 129 additions and 104 deletions
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67
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 1.163 2008/01/08 02:57:56 drh Exp $
** $Id: update.c,v 1.164 2008/01/08 18:57:50 drh Exp $
*/
#include "sqliteInt.h"
@@ -102,9 +102,6 @@ void sqlite3Update(
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
int iDb; /* Database containing the table being updated */
int memCnt = 0; /* Memory cell used for counting rows changed */
int mem1; /* Memory address storing the rowid for next row to update */
int iRowid; /* Memory address storing rowids */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* Trying to update a view */
@@ -120,6 +117,12 @@ void sqlite3Update(
int newIdx = -1; /* index of trigger "new" temp table */
int oldIdx = -1; /* index of trigger "old" temp table */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid; /* The old rowid */
int regNewRowid; /* The new rowid */
int regData; /* New data for the row */
sContext.pParse = 0;
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
@@ -251,13 +254,28 @@ void sqlite3Update(
aRegIdx[j] = reg;
}
/* Allocate a block of register used to store the change record
** sent to sqlite3GenerateConstraintChecks(). There are either
** one or two registers for holding the rowid. One rowid register
** is used if chngRowid is false and two are used if chngRowid is
** true. Following these are pTab->nCol register holding column
** data.
*/
regOldRowid = regNewRowid = pParse->nMem + 1;
pParse->nMem += pTab->nCol + 1;
if( chngRowid ){
regNewRowid++;
pParse->nMem++;
}
regData = regNewRowid+1;
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
mem1 = ++pParse->nMem;
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Virtual tables must be handled separately */
@@ -333,9 +351,8 @@ void sqlite3Update(
/* Remember the rowid of every item to be updated.
*/
iRowid = ++pParse->nMem;
sqlite3VdbeAddOp2(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid, iCur, iRowid);
sqlite3VdbeAddOp2(v, OP_FifoWrite, iRowid, 0);
sqlite3VdbeAddOp2(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid,iCur,regOldRowid);
sqlite3VdbeAddOp2(v, OP_FifoWrite, regOldRowid, 0);
/* End the database scan loop.
*/
@@ -344,8 +361,8 @@ void sqlite3Update(
/* Initialize the count of updated rows
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
memCnt = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
if( !isView && !IsVirtual(pTab) ){
@@ -383,13 +400,13 @@ void sqlite3Update(
}
/* Top of the update loop */
addr = sqlite3VdbeAddOp2(v, OP_FifoRead, iRowid, 0);
addr = sqlite3VdbeAddOp2(v, OP_FifoRead, regOldRowid, 0);
sqlite3VdbeAddOp2(v, OP_StackDepth, -1, 0);
if( triggers_exist ){
/* Make cursor iCur point to the record that is being updated.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, iRowid);
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* Generate the OLD table
*/
@@ -437,45 +454,44 @@ void sqlite3Update(
}
if( !isView && !IsVirtual(pTab) ){
/* Loop over every record that needs updating. We have to load
** the old data for each record to be updated because some columns
** might not change and we will need to copy the old value.
** Also, the old data is needed to delete the old index entries.
** So make the cursor point at the old record.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, iRowid);
sqlite3VdbeAddOp2(v, OP_SCopy, iRowid, 0);
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* If the record number will change, push the record number as it
** will be after the update. (The old record number is currently
** on top of the stack.)
*/
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, 0);
sqlite3VdbeAddOp2(v, OP_MustBeInt, 0, 0);
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp3(v, OP_MustBeInt, 0, 0, regNewRowid);
}
/* Compute new data for this record.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, 0);
sqlite3VdbeAddOp2(v, OP_Null, 0, regData+i);
continue;
}
j = aXRef[i];
if( j<0 ){
sqlite3VdbeAddOp2(v, OP_Column, iCur, i);
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regData+i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, 0);
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regData+i);
}
}
/* Do constraint checks
*/
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, aRegIdx, chngRowid, 1,
onError, addr);
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
aRegIdx, chngRowid, 1,
onError, addr);
/* Delete the old indices for the current record.
*/
@@ -489,13 +505,14 @@ void sqlite3Update(
/* Create the new index entries and the new record.
*/
sqlite3CompleteInsertion(pParse, pTab, iCur, aRegIdx, chngRowid, 1, -1, 0);
sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid,
aRegIdx, chngRowid, 1, -1, 0);
}
/* Increment the row counter
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
/* If there are triggers, close all the cursors after each iteration
@@ -530,7 +547,7 @@ void sqlite3Update(
** invoke the callback function.
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack && pParse->nested==0 ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", P4_STATIC);
}