mirror of
https://github.com/status-im/sqlcipher.git
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631 lines
22 KiB
C
631 lines
22 KiB
C
/*
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** 2001 September 15
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**
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** The author disclaims copyright to this source code. In place of
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** a legal notice, here is a blessing:
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**
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** May you do good and not evil.
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** May you find forgiveness for yourself and forgive others.
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** May you share freely, never taking more than you give.
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**
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*************************************************************************
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** This file contains C code routines that are called by the parser
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** in order to generate code for DELETE FROM statements.
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**
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** $Id: delete.c,v 1.191 2008/12/23 23:56:22 drh Exp $
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*/
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#include "sqliteInt.h"
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/*
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** Look up every table that is named in pSrc. If any table is not found,
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** add an error message to pParse->zErrMsg and return NULL. If all tables
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** are found, return a pointer to the last table.
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*/
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Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
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struct SrcList_item *pItem = pSrc->a;
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Table *pTab;
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assert( pItem && pSrc->nSrc==1 );
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pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
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sqlite3DeleteTable(pItem->pTab);
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pItem->pTab = pTab;
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if( pTab ){
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pTab->nRef++;
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}
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if( sqlite3IndexedByLookup(pParse, pItem) ){
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pTab = 0;
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}
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return pTab;
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}
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/*
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** Check to make sure the given table is writable. If it is not
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** writable, generate an error message and return 1. If it is
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** writable return 0;
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*/
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int sqlite3IsReadOnly(Parse *pParse, Table *pTab, int viewOk){
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if( ((pTab->tabFlags & TF_Readonly)!=0
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&& (pParse->db->flags & SQLITE_WriteSchema)==0
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&& pParse->nested==0)
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#ifndef SQLITE_OMIT_VIRTUALTABLE
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|| (pTab->pMod && pTab->pMod->pModule->xUpdate==0)
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#endif
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){
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sqlite3ErrorMsg(pParse, "table %s may not be modified", pTab->zName);
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return 1;
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}
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#ifndef SQLITE_OMIT_VIEW
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if( !viewOk && pTab->pSelect ){
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sqlite3ErrorMsg(pParse,"cannot modify %s because it is a view",pTab->zName);
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return 1;
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}
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#endif
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return 0;
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}
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/*
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** Generate code that will open a table for reading.
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*/
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void sqlite3OpenTable(
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Parse *p, /* Generate code into this VDBE */
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int iCur, /* The cursor number of the table */
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int iDb, /* The database index in sqlite3.aDb[] */
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Table *pTab, /* The table to be opened */
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int opcode /* OP_OpenRead or OP_OpenWrite */
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){
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Vdbe *v;
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if( IsVirtual(pTab) ) return;
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v = sqlite3GetVdbe(p);
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assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
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sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite)?1:0, pTab->zName);
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sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
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sqlite3VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb);
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VdbeComment((v, "%s", pTab->zName));
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}
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#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
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/*
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** Evaluate a view and store its result in an ephemeral table. The
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** pWhere argument is an optional WHERE clause that restricts the
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** set of rows in the view that are to be added to the ephemeral table.
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*/
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void sqlite3MaterializeView(
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Parse *pParse, /* Parsing context */
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Table *pView, /* View definition */
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Expr *pWhere, /* Optional WHERE clause to be added */
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int iCur /* Cursor number for ephemerial table */
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){
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SelectDest dest;
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Select *pDup;
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sqlite3 *db = pParse->db;
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pDup = sqlite3SelectDup(db, pView->pSelect);
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if( pWhere ){
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SrcList *pFrom;
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Token viewName;
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pWhere = sqlite3ExprDup(db, pWhere);
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viewName.z = (u8*)pView->zName;
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viewName.n = (unsigned int)sqlite3Strlen30((const char*)viewName.z);
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pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, &viewName, pDup, 0,0);
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pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
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}
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sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
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sqlite3Select(pParse, pDup, &dest);
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sqlite3SelectDelete(db, pDup);
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}
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#endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */
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#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
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/*
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** Generate an expression tree to implement the WHERE, ORDER BY,
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** and LIMIT/OFFSET portion of DELETE and UPDATE statements.
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**
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** DELETE FROM table_wxyz WHERE a<5 ORDER BY a LIMIT 1;
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** \__________________________/
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** pLimitWhere (pInClause)
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*/
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Expr *sqlite3LimitWhere(
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Parse *pParse, /* The parser context */
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SrcList *pSrc, /* the FROM clause -- which tables to scan */
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Expr *pWhere, /* The WHERE clause. May be null */
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ExprList *pOrderBy, /* The ORDER BY clause. May be null */
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Expr *pLimit, /* The LIMIT clause. May be null */
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Expr *pOffset, /* The OFFSET clause. May be null */
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char *zStmtType /* Either DELETE or UPDATE. For error messages. */
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){
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Expr *pWhereRowid = NULL; /* WHERE rowid .. */
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Expr *pInClause = NULL; /* WHERE rowid IN ( select ) */
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Expr *pSelectRowid = NULL; /* SELECT rowid ... */
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ExprList *pEList = NULL; /* Expression list contaning only pSelectRowid */
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SrcList *pSelectSrc = NULL; /* SELECT rowid FROM x ... (dup of pSrc) */
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Select *pSelect = NULL; /* Complete SELECT tree */
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/* Check that there isn't an ORDER BY without a LIMIT clause.
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*/
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if( pOrderBy && (pLimit == 0) ) {
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sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on %s", zStmtType);
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pParse->parseError = 1;
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goto limit_where_cleanup_2;
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}
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/* We only need to generate a select expression if there
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** is a limit/offset term to enforce.
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*/
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if( pLimit == 0 ) {
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/* if pLimit is null, pOffset will always be null as well. */
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assert( pOffset == 0 );
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return pWhere;
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}
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/* Generate a select expression tree to enforce the limit/offset
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** term for the DELETE or UPDATE statement. For example:
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** DELETE FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
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** becomes:
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** DELETE FROM table_a WHERE rowid IN (
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** SELECT rowid FROM table_a WHERE col1=1 ORDER BY col2 LIMIT 1 OFFSET 1
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** );
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*/
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pSelectRowid = sqlite3Expr(pParse->db, TK_ROW, 0, 0, 0);
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if( pSelectRowid == 0 ) goto limit_where_cleanup_2;
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pEList = sqlite3ExprListAppend(pParse, 0, pSelectRowid, 0);
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if( pEList == 0 ) goto limit_where_cleanup_2;
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/* duplicate the FROM clause as it is needed by both the DELETE/UPDATE tree
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** and the SELECT subtree. */
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pSelectSrc = sqlite3SrcListDup(pParse->db, pSrc);
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if( pSelectSrc == 0 ) {
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sqlite3ExprListDelete(pParse->db, pEList);
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goto limit_where_cleanup_2;
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}
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/* generate the SELECT expression tree. */
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pSelect = sqlite3SelectNew(pParse,pEList,pSelectSrc,pWhere,0,0,pOrderBy,0,pLimit,pOffset);
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if( pSelect == 0 ) return 0;
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/* now generate the new WHERE rowid IN clause for the DELETE/UDPATE */
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pWhereRowid = sqlite3Expr(pParse->db, TK_ROW, 0, 0, 0);
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if( pWhereRowid == 0 ) goto limit_where_cleanup_1;
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pInClause = sqlite3PExpr(pParse, TK_IN, pWhereRowid, 0, 0);
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if( pInClause == 0 ) goto limit_where_cleanup_1;
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pInClause->pSelect = pSelect;
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sqlite3ExprSetHeight(pParse, pInClause);
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return pInClause;
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/* something went wrong. clean up anything allocated. */
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limit_where_cleanup_1:
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sqlite3SelectDelete(pParse->db, pSelect);
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return 0;
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limit_where_cleanup_2:
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sqlite3ExprDelete(pParse->db, pWhere);
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sqlite3ExprListDelete(pParse->db, pOrderBy);
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sqlite3ExprDelete(pParse->db, pLimit);
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sqlite3ExprDelete(pParse->db, pOffset);
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return 0;
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}
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#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */
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/*
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** Generate code for a DELETE FROM statement.
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**
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** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
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** \________/ \________________/
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** pTabList pWhere
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*/
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void sqlite3DeleteFrom(
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Parse *pParse, /* The parser context */
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SrcList *pTabList, /* The table from which we should delete things */
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Expr *pWhere /* The WHERE clause. May be null */
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){
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Vdbe *v; /* The virtual database engine */
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Table *pTab; /* The table from which records will be deleted */
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const char *zDb; /* Name of database holding pTab */
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int end, addr = 0; /* A couple addresses of generated code */
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int i; /* Loop counter */
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WhereInfo *pWInfo; /* Information about the WHERE clause */
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Index *pIdx; /* For looping over indices of the table */
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int iCur; /* VDBE Cursor number for pTab */
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sqlite3 *db; /* Main database structure */
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AuthContext sContext; /* Authorization context */
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int oldIdx = -1; /* Cursor for the OLD table of AFTER triggers */
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NameContext sNC; /* Name context to resolve expressions in */
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int iDb; /* Database number */
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int memCnt = -1; /* Memory cell used for change counting */
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int rcauth; /* Value returned by authorization callback */
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#ifndef SQLITE_OMIT_TRIGGER
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int isView; /* True if attempting to delete from a view */
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int triggers_exist = 0; /* True if any triggers exist */
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#endif
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int iBeginAfterTrigger = 0; /* Address of after trigger program */
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int iEndAfterTrigger = 0; /* Exit of after trigger program */
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int iBeginBeforeTrigger = 0; /* Address of before trigger program */
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int iEndBeforeTrigger = 0; /* Exit of before trigger program */
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u32 old_col_mask = 0; /* Mask of OLD.* columns in use */
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sContext.pParse = 0;
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db = pParse->db;
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if( pParse->nErr || db->mallocFailed ){
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goto delete_from_cleanup;
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}
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assert( pTabList->nSrc==1 );
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/* Locate the table which we want to delete. This table has to be
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** put in an SrcList structure because some of the subroutines we
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** will be calling are designed to work with multiple tables and expect
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** an SrcList* parameter instead of just a Table* parameter.
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*/
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pTab = sqlite3SrcListLookup(pParse, pTabList);
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if( pTab==0 ) goto delete_from_cleanup;
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/* Figure out if we have any triggers and if the table being
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** deleted from is a view
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*/
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#ifndef SQLITE_OMIT_TRIGGER
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triggers_exist = sqlite3TriggersExist(pTab, TK_DELETE, 0);
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isView = pTab->pSelect!=0;
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#else
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# define triggers_exist 0
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# define isView 0
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#endif
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#ifdef SQLITE_OMIT_VIEW
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# undef isView
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# define isView 0
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#endif
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if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
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goto delete_from_cleanup;
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}
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iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
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assert( iDb<db->nDb );
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zDb = db->aDb[iDb].zName;
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rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
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assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
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if( rcauth==SQLITE_DENY ){
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goto delete_from_cleanup;
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}
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assert(!isView || triggers_exist);
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/* If pTab is really a view, make sure it has been initialized.
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*/
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if( sqlite3ViewGetColumnNames(pParse, pTab) ){
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goto delete_from_cleanup;
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}
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/* Allocate a cursor used to store the old.* data for a trigger.
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*/
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if( triggers_exist ){
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oldIdx = pParse->nTab++;
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}
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/* Assign cursor number to the table and all its indices.
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*/
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assert( pTabList->nSrc==1 );
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iCur = pTabList->a[0].iCursor = pParse->nTab++;
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for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
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pParse->nTab++;
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}
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|
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/* Start the view context
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*/
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if( isView ){
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sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
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}
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|
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/* Begin generating code.
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*/
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v = sqlite3GetVdbe(pParse);
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if( v==0 ){
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goto delete_from_cleanup;
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}
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if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
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sqlite3BeginWriteOperation(pParse, triggers_exist, iDb);
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if( triggers_exist ){
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int orconf = ((pParse->trigStack)?pParse->trigStack->orconf:OE_Default);
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int iGoto = sqlite3VdbeAddOp0(v, OP_Goto);
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addr = sqlite3VdbeMakeLabel(v);
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iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
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(void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_BEFORE, pTab,
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-1, oldIdx, orconf, addr, &old_col_mask, 0);
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iEndBeforeTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
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iBeginAfterTrigger = sqlite3VdbeCurrentAddr(v);
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(void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_AFTER, pTab, -1,
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oldIdx, orconf, addr, &old_col_mask, 0);
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iEndAfterTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
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sqlite3VdbeJumpHere(v, iGoto);
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}
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|
|
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/* If we are trying to delete from a view, realize that view into
|
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** a ephemeral table.
|
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*/
|
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#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
|
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if( isView ){
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sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
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}
|
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#endif
|
|
|
|
/* Resolve the column names in the WHERE clause.
|
|
*/
|
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memset(&sNC, 0, sizeof(sNC));
|
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sNC.pParse = pParse;
|
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sNC.pSrcList = pTabList;
|
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if( sqlite3ResolveExprNames(&sNC, pWhere) ){
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goto delete_from_cleanup;
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}
|
|
|
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/* Initialize the counter of the number of rows deleted, if
|
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** we are counting rows.
|
|
*/
|
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if( db->flags & SQLITE_CountRows ){
|
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memCnt = ++pParse->nMem;
|
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sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
|
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}
|
|
|
|
#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
|
|
/* Special case: A DELETE without a WHERE clause deletes everything.
|
|
** It is easier just to erase the whole table. Note, however, that
|
|
** this means that the row change count will be incorrect.
|
|
*/
|
|
if( rcauth==SQLITE_OK && pWhere==0 && !triggers_exist && !IsVirtual(pTab) ){
|
|
assert( !isView );
|
|
sqlite3VdbeAddOp3(v, OP_Clear, pTab->tnum, iDb, memCnt);
|
|
if( !pParse->nested ){
|
|
sqlite3VdbeChangeP4(v, -1, 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 iRowid = ++pParse->nMem; /* Used for storing rowid values. */
|
|
int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */
|
|
|
|
/* Collect rowids of every row to be deleted.
|
|
*/
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
|
|
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0,
|
|
WHERE_FILL_ROWSET, iRowSet);
|
|
if( pWInfo==0 ) goto delete_from_cleanup;
|
|
if( db->flags & SQLITE_CountRows ){
|
|
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
|
|
}
|
|
sqlite3WhereEnd(pWInfo);
|
|
|
|
/* Open the pseudo-table used to store OLD if there are triggers.
|
|
*/
|
|
if( triggers_exist ){
|
|
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
|
|
sqlite3VdbeAddOp1(v, OP_OpenPseudo, oldIdx);
|
|
}
|
|
|
|
/* 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);
|
|
|
|
if( !isView ){
|
|
/* Open cursors for the table we are deleting from and
|
|
** all its indices.
|
|
*/
|
|
sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
|
|
}
|
|
|
|
/* This is the beginning of the delete loop. If a trigger encounters
|
|
** an IGNORE constraint, it jumps back to here.
|
|
*/
|
|
if( triggers_exist ){
|
|
sqlite3VdbeResolveLabel(v, addr);
|
|
}
|
|
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
|
|
|
|
if( triggers_exist ){
|
|
int iData = ++pParse->nMem; /* For storing row data of OLD table */
|
|
|
|
/* If the record is no longer present in the table, jump to the
|
|
** next iteration of the loop through the contents of the fifo.
|
|
*/
|
|
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, iRowid);
|
|
|
|
/* Populate the OLD.* pseudo-table */
|
|
if( old_col_mask ){
|
|
sqlite3VdbeAddOp2(v, OP_RowData, iCur, iData);
|
|
}else{
|
|
sqlite3VdbeAddOp2(v, OP_Null, 0, iData);
|
|
}
|
|
sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, iData, iRowid);
|
|
|
|
/* Jump back and run the BEFORE triggers */
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
|
|
sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
|
|
}
|
|
|
|
if( !isView ){
|
|
/* Delete the row */
|
|
#ifndef SQLITE_OMIT_VIRTUALTABLE
|
|
if( IsVirtual(pTab) ){
|
|
const char *pVtab = (const char *)pTab->pVtab;
|
|
sqlite3VtabMakeWritable(pParse, pTab);
|
|
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVtab, P4_VTAB);
|
|
}else
|
|
#endif
|
|
{
|
|
sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, pParse->nested==0);
|
|
}
|
|
}
|
|
|
|
/* If there are row triggers, close all cursors then invoke
|
|
** the AFTER triggers
|
|
*/
|
|
if( triggers_exist ){
|
|
/* Jump back and run the AFTER triggers */
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
|
|
sqlite3VdbeJumpHere(v, iEndAfterTrigger);
|
|
}
|
|
|
|
/* End of the delete loop */
|
|
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
|
|
sqlite3VdbeResolveLabel(v, end);
|
|
|
|
/* Close the cursors after the loop if there are no row triggers */
|
|
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);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** 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==0 && !pParse->trigStack ){
|
|
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;
|
|
}
|
|
|
|
/*
|
|
** 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 "base".
|
|
**
|
|
** 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 pops the top of the stack to remove the record number
|
|
** and then 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 /* Increment the row change counter */
|
|
){
|
|
int addr;
|
|
Vdbe *v;
|
|
|
|
v = pParse->pVdbe;
|
|
addr = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, iRowid);
|
|
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
|
|
sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
|
|
if( count ){
|
|
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
|
|
}
|
|
sqlite3VdbeJumpHere(v, addr);
|
|
}
|
|
|
|
/*
|
|
** 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);
|
|
}
|
|
}
|
|
if( doMakeRec ){
|
|
sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
|
|
sqlite3IndexAffinityStr(v, pIdx);
|
|
sqlite3ExprCacheAffinityChange(pParse, regBase, nCol+1);
|
|
}
|
|
sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
|
|
return regBase;
|
|
}
|
|
|
|
/* Make sure "isView" gets undefined in case this file becomes part of
|
|
** the amalgamation - so that subsequent files do not see isView as a
|
|
** macro. */
|
|
#undef isView
|