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Copy pathdelete.c
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652 lines (591 loc) · 23.1 KB
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/*
** 2001 September 15
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** in order to generate code for DELETE FROM statements.
*/
#include "sqliteInt.h"
/*
** While a SrcList can in general represent multiple tables and subqueries
** (as in the FROM clause of a SELECT statement) in this case it contains
** the name of a single table, as one might find in an INSERT, DELETE,
** or UPDATE statement. Look up that table in the symbol table and
** return a pointer. Set an error message and return NULL if the table
** name is not found or if any other error occurs.
**
** The following fields are initialized appropriate in pSrc:
**
** pSrc->a[0].pTab Pointer to the Table object
** pSrc->a[0].pIndex Pointer to the INDEXED BY index, if there is one
**
*/
Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
struct SrcList_item *pItem = pSrc->a;
Table *pTab;
assert( pItem && pSrc->nSrc==1 );
pTab = sqlite3LocateTableItem(pParse, 0, pItem);
sqlite3DeleteTable(pParse->db, pItem->pTab);
pItem->pTab = pTab;
if( pTab ){
pTab->nRef++;
}
if( sqlite3IndexedByLookup(pParse, pItem) ){
pTab = 0;
}
return pTab;
}
/*
** Check to make sure the given table is writable. If it is not
** writable, generate an error message and return 1. If it is
** writable return 0;
*/
int sqlite3IsReadOnly(Parse *pParse, Table *pTab, int viewOk){
/* A table is not writable under the following circumstances:
**
** 1) It is a virtual table and no implementation of the xUpdate method
** has been provided, or
** 2) It is a system table (i.e. sqlite_master), this call is not
** part of a nested parse and writable_schema pragma has not
** been specified.
**
** In either case leave an error message in pParse and return non-zero.
*/
if( ( IsVirtual(pTab)
&& sqlite3GetVTable(pParse->db, pTab)->pMod->pModule->xUpdate==0 )
|| ( (pTab->tabFlags & TF_Readonly)!=0
&& (pParse->db->flags & SQLITE_WriteSchema)==0
&& pParse->nested==0 )
){
sqlite3ErrorMsg(pParse, "table %s may not be modified", pTab->zName);
return 1;
}
#ifndef SQLITE_OMIT_VIEW
if( !viewOk && pTab->pSelect ){
sqlite3ErrorMsg(pParse,"cannot modify %s because it is a view",pTab->zName);
return 1;
}
#endif
return 0;
}
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
/*
** Evaluate a view and store its result in an ephemeral table. The
** pWhere argument is an optional WHERE clause that restricts the
** set of rows in the view that are to be added to the ephemeral table.
*/
void sqlite3MaterializeView(
Parse *pParse, /* Parsing context */
Table *pView, /* View definition */
Expr *pWhere, /* Optional WHERE clause to be added */
int iCur /* Cursor number for ephemerial table */
){
SelectDest dest;
Select *pSel;
SrcList *pFrom;
sqlite3 *db = pParse->db;
int iDb = sqlite3SchemaToIndex(db, pView->pSchema);
pWhere = sqlite3ExprDup(db, pWhere, 0);
pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
if( pFrom ){
assert( pFrom->nSrc==1 );
pFrom->a[0].zName = sqlite3DbStrDup(db, pView->zName);
pFrom->a[0].zDatabase = sqlite3DbStrDup(db, db->aDb[iDb].zName);
assert( pFrom->a[0].pOn==0 );
assert( pFrom->a[0].pUsing==0 );
}
pSel = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
if( pSel ) pSel->selFlags |= SF_Materialize;
sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
sqlite3Select(pParse, pSel, &dest);
sqlite3SelectDelete(db, pSel);
}
#endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */
#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
/*
** Generate an expression tree to implement the WHERE, ORDER BY,
** and LIMIT/OFFSET portion of DELETE and UPDATE statements.
**
** DELETE FROM table_wxyz WHERE a<5 ORDER BY a LIMIT 1;
** \__________________________/
** pLimitWhere (pInClause)
*/
Expr *sqlite3LimitWhere(
Parse *pParse, /* The parser context */
SrcList *pSrc, /* the FROM clause -- which tables to scan */
Expr *pWhere, /* The WHERE clause. May be null */
ExprList *pOrderBy, /* The ORDER BY clause. May be null */
Expr *pLimit, /* The LIMIT clause. May be null */
Expr *pOffset, /* The OFFSET clause. May be null */
char *zStmtType /* Either DELETE or UPDATE. For error messages. */
){
Expr *pWhereRowid = NULL; /* WHERE rowid .. */
Expr *pInClause = NULL; /* WHERE rowid IN ( select ) */
Expr *pSelectRowid = NULL; /* SELECT rowid ... */
ExprList *pEList = NULL; /* Expression list contaning only pSelectRowid */
SrcList *pSelectSrc = NULL; /* SELECT rowid FROM x ... (dup of pSrc) */
Select *pSelect = NULL; /* Complete SELECT tree */
/* Check that there isn't an ORDER BY without a LIMIT clause.
*/
if( pOrderBy && (pLimit == 0) ) {
sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on %s", zStmtType);
goto limit_where_cleanup_2;
}
/* We only need to generate a select expression if there
** is a limit/offset term to enforce.
*/
if( pLimit == 0 ) {
/* if pLimit is null, pOffset will always be null as well. */
assert( pOffset == 0 );
return pWhere;
}
/* Generate a select expression tree to enforce the limit/offset
** term for the DELETE or UPDATE statement. For example:
** DELETE FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
** becomes:
** DELETE FROM table_a WHERE rowid IN (
** SELECT rowid FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
** );
*/
pSelectRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0, 0);
if( pSelectRowid == 0 ) goto limit_where_cleanup_2;
pEList = sqlite3ExprListAppend(pParse, 0, pSelectRowid);
if( pEList == 0 ) goto limit_where_cleanup_2;
/* duplicate the FROM clause as it is needed by both the DELETE/UPDATE tree
** and the SELECT subtree. */
pSelectSrc = sqlite3SrcListDup(pParse->db, pSrc, 0);
if( pSelectSrc == 0 ) {
sqlite3ExprListDelete(pParse->db, pEList);
goto limit_where_cleanup_2;
}
/* generate the SELECT expression tree. */
pSelect = sqlite3SelectNew(pParse,pEList,pSelectSrc,pWhere,0,0,
pOrderBy,0,pLimit,pOffset);
if( pSelect == 0 ) return 0;
/* now generate the new WHERE rowid IN clause for the DELETE/UDPATE */
pWhereRowid = sqlite3PExpr(pParse, TK_ROW, 0, 0, 0);
if( pWhereRowid == 0 ) goto limit_where_cleanup_1;
pInClause = sqlite3PExpr(pParse, TK_IN, pWhereRowid, 0, 0);
if( pInClause == 0 ) goto limit_where_cleanup_1;
pInClause->x.pSelect = pSelect;
pInClause->flags |= EP_xIsSelect;
sqlite3ExprSetHeight(pParse, pInClause);
return pInClause;
/* something went wrong. clean up anything allocated. */
limit_where_cleanup_1:
sqlite3SelectDelete(pParse->db, pSelect);
return 0;
limit_where_cleanup_2:
sqlite3ExprDelete(pParse->db, pWhere);
sqlite3ExprListDelete(pParse->db, pOrderBy);
sqlite3ExprDelete(pParse->db, pLimit);
sqlite3ExprDelete(pParse->db, pOffset);
return 0;
}
#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */
/*
** Generate code for a DELETE FROM statement.
**
** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
** \________/ \________________/
** pTabList pWhere
*/
void sqlite3DeleteFrom(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table from which we should delete things */
Expr *pWhere /* The WHERE clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
const char *zDb; /* Name of database holding pTab */
int end, addr = 0; /* A couple addresses of generated code */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
int iCur; /* VDBE Cursor number for pTab */
sqlite3 *db; /* Main database structure */
AuthContext sContext; /* Authorization context */
NameContext sNC; /* Name context to resolve expressions in */
int iDb; /* Database number */
int memCnt = -1; /* Memory cell used for change counting */
int rcauth; /* Value returned by authorization callback */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
Trigger *pTrigger; /* List of table triggers, if required */
#endif
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto delete_from_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to delete. This table has to be
** put in an SrcList structure because some of the subroutines we
** will be calling are designed to work with multiple tables and expect
** an SrcList* parameter instead of just a Table* parameter.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto delete_from_cleanup;
/* Figure out if we have any triggers and if the table being
** deleted from is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
isView = pTab->pSelect!=0;
#else
# define pTrigger 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
/* If pTab is really a view, make sure it has been initialized.
*/
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto delete_from_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
goto delete_from_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
zDb = db->aDb[iDb].zName;
rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
if( rcauth==SQLITE_DENY ){
goto delete_from_cleanup;
}
assert(!isView || pTrigger);
/* Assign cursor number to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iCur = pTabList->a[0].iCursor = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto delete_from_cleanup;
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
/* If we are trying to delete from a view, realize that view into
** a ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
/* Resolve the column names in the WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto delete_from_cleanup;
}
/* Initialize the counter of the number of rows deleted, if
** we are counting rows.
*/
if( db->flags & SQLITE_CountRows ){
memCnt = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
}
#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
/* Special case: A DELETE without a WHERE clause deletes everything.
** It is easier just to erase the whole table. Prior to version 3.6.5,
** this optimization caused the row change count (the value returned by
** API function sqlite3_count_changes) to be set incorrectly. */
if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab)
&& 0==sqlite3FkRequired(pParse, pTab, 0, 0)
){
assert( !isView );
sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
pTab->zName, P4_STATIC);
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
}
}else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
/* The usual case: There is a WHERE clause so we have to scan through
** the table and pick which records to delete.
*/
{
int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */
int iRowid = ++pParse->nMem; /* Used for storing rowid values. */
int regRowid; /* Actual register containing rowids */
/* Collect rowids of every row to be deleted.
*/
sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
pWInfo = sqlite3WhereBegin(
pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK, 0
);
if( pWInfo==0 ) goto delete_from_cleanup;
regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
sqlite3WhereEnd(pWInfo);
/* Delete every item whose key was written to the list during the
** database scan. We have to delete items after the scan is complete
** because deleting an item can change the scan order. */
end = sqlite3VdbeMakeLabel(v);
/* Unless this is a view, open cursors for the table we are
** deleting from and all its indices. If this is a view, then the
** only effect this statement has is to fire the INSTEAD OF
** triggers. */
if( !isView ){
sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
}
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
/* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, OE_Abort);
sqlite3MayAbort(pParse);
}else
#endif
{
int count = (pParse->nested==0); /* True to count changes */
sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, count, pTrigger, OE_Default);
}
/* End of the delete loop */
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeResolveLabel(v, end);
/* Close the cursors open on the table and its indexes. */
if( !isView && !IsVirtual(pTab) ){
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
}
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
}
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/* Return the number of rows that were deleted. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);
}
delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
return;
}
/* Make sure "isView" and other macros defined above are undefined. Otherwise
** thely may interfere with compilation of other functions in this file
** (or in another file, if this file becomes part of the amalgamation). */
#ifdef isView
#undef isView
#endif
#ifdef pTrigger
#undef pTrigger
#endif
/*
** This routine generates VDBE code that causes a single row of a
** single table to be deleted.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
**
** 1. A read/write cursor pointing to pTab, the table containing the row
** to be deleted, must be opened as cursor number $iCur.
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number base+i for the i-th index.
**
** 3. The record number of the row to be deleted must be stored in
** memory cell iRowid.
**
** This routine generates code to remove both the table record and all
** index entries that point to that record.
*/
void sqlite3GenerateRowDelete(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table containing the row to be deleted */
int iCur, /* Cursor number for the table */
int iRowid, /* Memory cell that contains the rowid to delete */
int count, /* If non-zero, increment the row change counter */
Trigger *pTrigger, /* List of triggers to (potentially) fire */
int onconf /* Default ON CONFLICT policy for triggers */
){
Vdbe *v = pParse->pVdbe; /* Vdbe */
int iOld = 0; /* First register in OLD.* array */
int iLabel; /* Label resolved to end of generated code */
/* Vdbe is guaranteed to have been allocated by this stage. */
assert( v );
/* Seek cursor iCur to the row to delete. If this row no longer exists
** (this can happen if a trigger program has already deleted it), do
** not attempt to delete it or fire any DELETE triggers. */
iLabel = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
/* If there are any triggers to fire, allocate a range of registers to
** use for the old.* references in the triggers. */
if( sqlite3FkRequired(pParse, pTab, 0, 0) || pTrigger ){
u32 mask; /* Mask of OLD.* columns in use */
int iCol; /* Iterator used while populating OLD.* */
/* TODO: Could use temporary registers here. Also could attempt to
** avoid copying the contents of the rowid register. */
mask = sqlite3TriggerColmask(
pParse, pTrigger, 0, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onconf
);
mask |= sqlite3FkOldmask(pParse, pTab);
iOld = pParse->nMem+1;
pParse->nMem += (1 + pTab->nCol);
/* Populate the OLD.* pseudo-table register array. These values will be
** used by any BEFORE and AFTER triggers that exist. */
sqlite3VdbeAddOp2(v, OP_Copy, iRowid, iOld);
for(iCol=0; iCol<pTab->nCol; iCol++){
if( mask==0xffffffff || mask&(1<<iCol) ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, iCol, iOld+iCol+1);
}
}
/* Invoke BEFORE DELETE trigger programs. */
sqlite3CodeRowTrigger(pParse, pTrigger,
TK_DELETE, 0, TRIGGER_BEFORE, pTab, iOld, onconf, iLabel
);
/* Seek the cursor to the row to be deleted again. It may be that
** the BEFORE triggers coded above have already removed the row
** being deleted. Do not attempt to delete the row a second time, and
** do not fire AFTER triggers. */
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
/* Do FK processing. This call checks that any FK constraints that
** refer to this table (i.e. constraints attached to other tables)
** are not violated by deleting this row. */
sqlite3FkCheck(pParse, pTab, iOld, 0);
}
/* Delete the index and table entries. Skip this step if pTab is really
** a view (in which case the only effect of the DELETE statement is to
** fire the INSTEAD OF triggers). */
if( pTab->pSelect==0 ){
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
if( count ){
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
}
}
/* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
** handle rows (possibly in other tables) that refer via a foreign key
** to the row just deleted. */
sqlite3FkActions(pParse, pTab, 0, iOld);
/* Invoke AFTER DELETE trigger programs. */
sqlite3CodeRowTrigger(pParse, pTrigger,
TK_DELETE, 0, TRIGGER_AFTER, pTab, iOld, onconf, iLabel
);
/* Jump here if the row had already been deleted before any BEFORE
** trigger programs were invoked. Or if a trigger program throws a
** RAISE(IGNORE) exception. */
sqlite3VdbeResolveLabel(v, iLabel);
}
/*
** This routine generates VDBE code that causes the deletion of all
** index entries associated with a single row of a single table.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
**
** 1. A read/write cursor pointing to pTab, the table containing the row
** to be deleted, must be opened as cursor number "iCur".
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number iCur+i for the i-th index.
**
** 3. The "iCur" cursor must be pointing to the row that is to be
** deleted.
*/
void sqlite3GenerateRowIndexDelete(
Parse *pParse, /* Parsing and code generating context */
Table *pTab, /* Table containing the row to be deleted */
int iCur, /* Cursor number for the table */
int *aRegIdx /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
){
int i;
Index *pIdx;
int r1;
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
}
}
/*
** Generate code that will assemble an index key and put it in register
** regOut. The key with be for index pIdx which is an index on pTab.
** iCur is the index of a cursor open on the pTab table and pointing to
** the entry that needs indexing.
**
** Return a register number which is the first in a block of
** registers that holds the elements of the index key. The
** block of registers has already been deallocated by the time
** this routine returns.
*/
int sqlite3GenerateIndexKey(
Parse *pParse, /* Parsing context */
Index *pIdx, /* The index for which to generate a key */
int iCur, /* Cursor number for the pIdx->pTable table */
int regOut, /* Write the new index key to this register */
int doMakeRec /* Run the OP_MakeRecord instruction if true */
){
Vdbe *v = pParse->pVdbe;
int j;
Table *pTab = pIdx->pTable;
int regBase;
int nCol;
nCol = pIdx->nColumn;
regBase = sqlite3GetTempRange(pParse, nCol+1);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
for(j=0; j<nCol; j++){
int idx = pIdx->aiColumn[j];
if( idx==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);
}else{
sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);
sqlite3ColumnDefault(v, pTab, idx, -1);
}
}
if( doMakeRec ){
const char *zAff;
if( pTab->pSelect
|| OptimizationDisabled(pParse->db, SQLITE_IdxRealAsInt)
){
zAff = 0;
}else{
zAff = sqlite3IndexAffinityStr(v, pIdx);
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
sqlite3VdbeChangeP4(v, -1, zAff, P4_TRANSIENT);
}
sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
return regBase;
}