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authorHans-Christoph Steiner <hans@eds.org>2012-03-30 20:42:12 -0400
committerHans-Christoph Steiner <hans@eds.org>2012-03-30 20:42:12 -0400
commit7bb481fda9ecb134804b49c2ce77ca28f7eea583 (patch)
tree31b520b9914d3e2453968abe375f2c102772c3dc /src/delete.c
Imported Upstream version 2.0.3
Diffstat (limited to 'src/delete.c')
-rw-r--r--src/delete.c652
1 files changed, 652 insertions, 0 deletions
diff --git a/src/delete.c b/src/delete.c
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index 0000000..147a5ca
--- /dev/null
+++ b/src/delete.c
@@ -0,0 +1,652 @@
+/*
+** 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 = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
+ 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 *pDup;
+ sqlite3 *db = pParse->db;
+
+ pDup = sqlite3SelectDup(db, pView->pSelect, 0);
+ if( pWhere ){
+ SrcList *pFrom;
+
+ pWhere = sqlite3ExprDup(db, pWhere, 0);
+ pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
+ if( pFrom ){
+ assert( pFrom->nSrc==1 );
+ pFrom->a[0].zAlias = sqlite3DbStrDup(db, pView->zName);
+ pFrom->a[0].pSelect = pDup;
+ assert( pFrom->a[0].pOn==0 );
+ assert( pFrom->a[0].pUsing==0 );
+ }else{
+ sqlite3SelectDelete(db, pDup);
+ }
+ pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
+ }
+ sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
+ sqlite3Select(pParse, pDup, &dest);
+ sqlite3SelectDelete(db, pDup);
+}
+#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);
+ pParse->parseError = 1;
+ 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
+ );
+ if( pWInfo==0 ) goto delete_from_cleanup;
+ regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid);
+ 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 || (pParse->db->flags & SQLITE_IdxRealAsInt)!=0 ){
+ 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;
+}