251cced1f8
Various minor things done to project files Updated sample extension project file and updated makefile to the new unified version (more changes likely on the way) Updated regex project file and makefile --HG-- extra : convert_revision : svn%3A39bc706e-5318-0410-9160-8a85361fbb7c/trunk%401971
631 lines
21 KiB
C
631 lines
21 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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** to handle UPDATE statements.
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**
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** $Id$
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*/
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#include "sqliteInt.h"
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#ifndef SQLITE_OMIT_VIRTUALTABLE
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/* Forward declaration */
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static void updateVirtualTable(
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Parse *pParse, /* The parsing context */
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SrcList *pSrc, /* The virtual table to be modified */
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Table *pTab, /* The virtual table */
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ExprList *pChanges, /* The columns to change in the UPDATE statement */
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Expr *pRowidExpr, /* Expression used to recompute the rowid */
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int *aXRef, /* Mapping from columns of pTab to entries in pChanges */
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Expr *pWhere /* WHERE clause of the UPDATE statement */
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);
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#endif /* SQLITE_OMIT_VIRTUALTABLE */
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/*
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** The most recently coded instruction was an OP_Column to retrieve the
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** i-th column of table pTab. This routine sets the P3 parameter of the
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** OP_Column to the default value, if any.
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**
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** The default value of a column is specified by a DEFAULT clause in the
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** column definition. This was either supplied by the user when the table
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** was created, or added later to the table definition by an ALTER TABLE
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** command. If the latter, then the row-records in the table btree on disk
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** may not contain a value for the column and the default value, taken
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** from the P3 parameter of the OP_Column instruction, is returned instead.
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** If the former, then all row-records are guaranteed to include a value
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** for the column and the P3 value is not required.
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**
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** Column definitions created by an ALTER TABLE command may only have
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** literal default values specified: a number, null or a string. (If a more
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** complicated default expression value was provided, it is evaluated
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** when the ALTER TABLE is executed and one of the literal values written
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** into the sqlite_master table.)
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**
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** Therefore, the P3 parameter is only required if the default value for
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** the column is a literal number, string or null. The sqlite3ValueFromExpr()
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** function is capable of transforming these types of expressions into
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** sqlite3_value objects.
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*/
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void sqlite3ColumnDefault(Vdbe *v, Table *pTab, int i){
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if( pTab && !pTab->pSelect ){
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sqlite3_value *pValue;
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u8 enc = ENC(sqlite3VdbeDb(v));
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Column *pCol = &pTab->aCol[i];
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assert( i<pTab->nCol );
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sqlite3ValueFromExpr(sqlite3VdbeDb(v), pCol->pDflt, enc, pCol->affinity, &pValue);
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if( pValue ){
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sqlite3VdbeChangeP3(v, -1, (const char *)pValue, P3_MEM);
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}else{
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VdbeComment((v, "# %s.%s", pTab->zName, pCol->zName));
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}
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}
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}
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/*
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** Process an UPDATE statement.
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**
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** UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
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** \_______/ \________/ \______/ \________________/
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* onError pTabList pChanges pWhere
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*/
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void sqlite3Update(
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Parse *pParse, /* The parser context */
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SrcList *pTabList, /* The table in which we should change things */
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ExprList *pChanges, /* Things to be changed */
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Expr *pWhere, /* The WHERE clause. May be null */
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int onError /* How to handle constraint errors */
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){
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int i, j; /* Loop counters */
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Table *pTab; /* The table to be updated */
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int addr = 0; /* VDBE instruction address of the start of the loop */
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WhereInfo *pWInfo; /* Information about the WHERE clause */
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Vdbe *v; /* The virtual database engine */
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Index *pIdx; /* For looping over indices */
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int nIdx; /* Number of indices that need updating */
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int nIdxTotal; /* Total number of indices */
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int iCur; /* VDBE Cursor number of pTab */
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sqlite3 *db; /* The database structure */
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Index **apIdx = 0; /* An array of indices that need updating too */
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char *aIdxUsed = 0; /* aIdxUsed[i]==1 if the i-th index is used */
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int *aXRef = 0; /* aXRef[i] is the index in pChanges->a[] of the
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** an expression for the i-th column of the table.
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** aXRef[i]==-1 if the i-th column is not changed. */
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int chngRowid; /* True if the record number is being changed */
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Expr *pRowidExpr = 0; /* Expression defining the new record number */
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int openAll = 0; /* True if all indices need to be opened */
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AuthContext sContext; /* The authorization context */
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NameContext sNC; /* The name-context to resolve expressions in */
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int iDb; /* Database containing the table being updated */
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int memCnt = 0; /* Memory cell used for counting rows changed */
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#ifndef SQLITE_OMIT_TRIGGER
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int isView; /* Trying to update a view */
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int triggers_exist = 0; /* True if any row triggers exist */
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#endif
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int newIdx = -1; /* index of trigger "new" temp table */
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int oldIdx = -1; /* index of trigger "old" temp table */
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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 update_cleanup;
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}
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assert( pTabList->nSrc==1 );
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/* Locate the table which we want to update.
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*/
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pTab = sqlite3SrcListLookup(pParse, pTabList);
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if( pTab==0 ) goto update_cleanup;
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iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
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/* Figure out if we have any triggers and if the table being
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** updated is a view
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*/
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#ifndef SQLITE_OMIT_TRIGGER
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triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges);
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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 update_cleanup;
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}
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if( sqlite3ViewGetColumnNames(pParse, pTab) ){
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goto update_cleanup;
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}
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aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
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if( aXRef==0 ) goto update_cleanup;
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for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
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/* If there are FOR EACH ROW triggers, allocate cursors for the
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** special OLD and NEW tables
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*/
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if( triggers_exist ){
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newIdx = pParse->nTab++;
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oldIdx = pParse->nTab++;
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}
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/* Allocate a cursors for the main database table and for all indices.
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** The index cursors might not be used, but if they are used they
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** need to occur right after the database cursor. So go ahead and
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** allocate enough space, just in case.
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*/
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pTabList->a[0].iCursor = iCur = 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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/* Initialize the name-context */
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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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/* Resolve the column names in all the expressions of the
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** of the UPDATE statement. Also find the column index
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** for each column to be updated in the pChanges array. For each
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** column to be updated, make sure we have authorization to change
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** that column.
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*/
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chngRowid = 0;
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for(i=0; i<pChanges->nExpr; i++){
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if( sqlite3ExprResolveNames(&sNC, pChanges->a[i].pExpr) ){
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goto update_cleanup;
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}
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for(j=0; j<pTab->nCol; j++){
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if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
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if( j==pTab->iPKey ){
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chngRowid = 1;
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pRowidExpr = pChanges->a[i].pExpr;
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}
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aXRef[j] = i;
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break;
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}
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}
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if( j>=pTab->nCol ){
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if( sqlite3IsRowid(pChanges->a[i].zName) ){
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chngRowid = 1;
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pRowidExpr = pChanges->a[i].pExpr;
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}else{
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sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
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goto update_cleanup;
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}
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}
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#ifndef SQLITE_OMIT_AUTHORIZATION
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{
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int rc;
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rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
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pTab->aCol[j].zName, db->aDb[iDb].zName);
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if( rc==SQLITE_DENY ){
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goto update_cleanup;
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}else if( rc==SQLITE_IGNORE ){
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aXRef[j] = -1;
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}
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}
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#endif
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}
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/* Allocate memory for the array apIdx[] and fill it with pointers to every
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** index that needs to be updated. Indices only need updating if their
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** key includes one of the columns named in pChanges or if the record
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** number of the original table entry is changing.
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*/
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for(nIdx=nIdxTotal=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdxTotal++){
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if( chngRowid ){
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i = 0;
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}else {
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for(i=0; i<pIdx->nColumn; i++){
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if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
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}
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}
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if( i<pIdx->nColumn ) nIdx++;
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}
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if( nIdxTotal>0 ){
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apIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx + nIdxTotal );
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if( apIdx==0 ) goto update_cleanup;
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aIdxUsed = (char*)&apIdx[nIdx];
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}
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for(nIdx=j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
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if( chngRowid ){
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i = 0;
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}else{
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for(i=0; i<pIdx->nColumn; i++){
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if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
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}
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}
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if( i<pIdx->nColumn ){
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apIdx[nIdx++] = pIdx;
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aIdxUsed[j] = 1;
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}else{
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aIdxUsed[j] = 0;
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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 ) goto update_cleanup;
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if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
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sqlite3BeginWriteOperation(pParse, 1, iDb);
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#ifndef SQLITE_OMIT_VIRTUALTABLE
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/* Virtual tables must be handled separately */
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if( IsVirtual(pTab) ){
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updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
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pWhere);
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pWhere = 0;
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pTabList = 0;
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goto update_cleanup;
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}
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#endif
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/* Resolve the column names in all the expressions in the
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** WHERE clause.
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*/
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if( sqlite3ExprResolveNames(&sNC, pWhere) ){
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goto update_cleanup;
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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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/* If we are trying to update a view, realize that view into
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** a ephemeral table.
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*/
|
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if( isView ){
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Select *pView;
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pView = sqlite3SelectDup(db, pTab->pSelect);
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sqlite3Select(pParse, pView, SRT_EphemTab, iCur, 0, 0, 0, 0);
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sqlite3SelectDelete(pView);
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}
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|
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/* Begin the database scan
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*/
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pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0);
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if( pWInfo==0 ) goto update_cleanup;
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|
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/* Remember the rowid of every item to be updated.
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*/
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sqlite3VdbeAddOp(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid, iCur, 0);
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sqlite3VdbeAddOp(v, OP_FifoWrite, 0, 0);
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/* End the database scan loop.
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*/
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sqlite3WhereEnd(pWInfo);
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|
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/* Initialize the count of updated rows
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*/
|
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if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
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memCnt = pParse->nMem++;
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sqlite3VdbeAddOp(v, OP_MemInt, 0, memCnt);
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}
|
|
|
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if( triggers_exist ){
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/* Create pseudo-tables for NEW and OLD
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*/
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sqlite3VdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
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sqlite3VdbeAddOp(v, OP_SetNumColumns, oldIdx, pTab->nCol);
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sqlite3VdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
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sqlite3VdbeAddOp(v, OP_SetNumColumns, newIdx, pTab->nCol);
|
|
|
|
/* The top of the update loop for when there are triggers.
|
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*/
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addr = sqlite3VdbeAddOp(v, OP_FifoRead, 0, 0);
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|
|
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if( !isView ){
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sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
|
|
sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
|
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/* Open a cursor and make it point to the record that is
|
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** being updated.
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*/
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sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
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}
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sqlite3VdbeAddOp(v, OP_MoveGe, iCur, 0);
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|
|
|
/* Generate the OLD table
|
|
*/
|
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sqlite3VdbeAddOp(v, OP_Rowid, iCur, 0);
|
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sqlite3VdbeAddOp(v, OP_RowData, iCur, 0);
|
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sqlite3VdbeAddOp(v, OP_Insert, oldIdx, 0);
|
|
|
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/* Generate the NEW table
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*/
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if( chngRowid ){
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sqlite3ExprCodeAndCache(pParse, pRowidExpr);
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}else{
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sqlite3VdbeAddOp(v, OP_Rowid, iCur, 0);
|
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}
|
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for(i=0; i<pTab->nCol; i++){
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if( i==pTab->iPKey ){
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sqlite3VdbeAddOp(v, OP_Null, 0, 0);
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continue;
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}
|
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j = aXRef[i];
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if( j<0 ){
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sqlite3VdbeAddOp(v, OP_Column, iCur, i);
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|
sqlite3ColumnDefault(v, pTab, i);
|
|
}else{
|
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sqlite3ExprCodeAndCache(pParse, pChanges->a[j].pExpr);
|
|
}
|
|
}
|
|
sqlite3VdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
|
|
if( !isView ){
|
|
sqlite3TableAffinityStr(v, pTab);
|
|
}
|
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if( pParse->nErr ) goto update_cleanup;
|
|
sqlite3VdbeAddOp(v, OP_Insert, newIdx, 0);
|
|
if( !isView ){
|
|
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
|
|
}
|
|
|
|
/* Fire the BEFORE and INSTEAD OF triggers
|
|
*/
|
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if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_BEFORE, pTab,
|
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newIdx, oldIdx, onError, addr) ){
|
|
goto update_cleanup;
|
|
}
|
|
}
|
|
|
|
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
|
|
** 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.
|
|
*/
|
|
if( !triggers_exist ){
|
|
addr = sqlite3VdbeAddOp(v, OP_FifoRead, 0, 0);
|
|
sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
|
|
}
|
|
sqlite3VdbeAddOp(v, OP_NotExists, iCur, addr);
|
|
|
|
/* 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);
|
|
sqlite3VdbeAddOp(v, OP_MustBeInt, 0, 0);
|
|
}
|
|
|
|
/* Compute new data for this record.
|
|
*/
|
|
for(i=0; i<pTab->nCol; i++){
|
|
if( i==pTab->iPKey ){
|
|
sqlite3VdbeAddOp(v, OP_Null, 0, 0);
|
|
continue;
|
|
}
|
|
j = aXRef[i];
|
|
if( j<0 ){
|
|
sqlite3VdbeAddOp(v, OP_Column, iCur, i);
|
|
sqlite3ColumnDefault(v, pTab, i);
|
|
}else{
|
|
sqlite3ExprCode(pParse, pChanges->a[j].pExpr);
|
|
}
|
|
}
|
|
|
|
/* Do constraint checks
|
|
*/
|
|
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, aIdxUsed, chngRowid, 1,
|
|
onError, addr);
|
|
|
|
/* Delete the old indices for the current record.
|
|
*/
|
|
sqlite3GenerateRowIndexDelete(v, pTab, iCur, aIdxUsed);
|
|
|
|
/* If changing the record number, delete the old record.
|
|
*/
|
|
if( chngRowid ){
|
|
sqlite3VdbeAddOp(v, OP_Delete, iCur, 0);
|
|
}
|
|
|
|
/* Create the new index entries and the new record.
|
|
*/
|
|
sqlite3CompleteInsertion(pParse, pTab, iCur, aIdxUsed, chngRowid, 1, -1, 0);
|
|
}
|
|
|
|
/* Increment the row counter
|
|
*/
|
|
if( db->flags & SQLITE_CountRows && !pParse->trigStack){
|
|
sqlite3VdbeAddOp(v, OP_MemIncr, 1, memCnt);
|
|
}
|
|
|
|
/* If there are triggers, close all the cursors after each iteration
|
|
** 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);
|
|
}
|
|
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_AFTER, pTab,
|
|
newIdx, oldIdx, onError, addr) ){
|
|
goto update_cleanup;
|
|
}
|
|
}
|
|
|
|
/* Repeat the above with the next record to be updated, until
|
|
** all record selected by the WHERE clause have been updated.
|
|
*/
|
|
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);
|
|
}
|
|
}
|
|
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
|
|
}else{
|
|
sqlite3VdbeAddOp(v, OP_Close, newIdx, 0);
|
|
sqlite3VdbeAddOp(v, OP_Close, oldIdx, 0);
|
|
}
|
|
|
|
/*
|
|
** Return the number of rows that were changed. If this routine is
|
|
** generating code because of a call to sqlite3NestedParse(), do not
|
|
** invoke the callback function.
|
|
*/
|
|
if( db->flags & SQLITE_CountRows && !pParse->trigStack && pParse->nested==0 ){
|
|
sqlite3VdbeAddOp(v, OP_MemLoad, memCnt, 0);
|
|
sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
|
|
sqlite3VdbeSetNumCols(v, 1);
|
|
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", P3_STATIC);
|
|
}
|
|
|
|
update_cleanup:
|
|
sqlite3AuthContextPop(&sContext);
|
|
sqlite3_free(apIdx);
|
|
sqlite3_free(aXRef);
|
|
sqlite3SrcListDelete(pTabList);
|
|
sqlite3ExprListDelete(pChanges);
|
|
sqlite3ExprDelete(pWhere);
|
|
return;
|
|
}
|
|
|
|
#ifndef SQLITE_OMIT_VIRTUALTABLE
|
|
/*
|
|
** Generate code for an UPDATE of a virtual table.
|
|
**
|
|
** The strategy is that we create an ephemerial table that contains
|
|
** for each row to be changed:
|
|
**
|
|
** (A) The original rowid of that row.
|
|
** (B) The revised rowid for the row. (note1)
|
|
** (C) The content of every column in the row.
|
|
**
|
|
** Then we loop over this ephemeral table and for each row in
|
|
** the ephermeral table call VUpdate.
|
|
**
|
|
** When finished, drop the ephemeral table.
|
|
**
|
|
** (note1) Actually, if we know in advance that (A) is always the same
|
|
** as (B) we only store (A), then duplicate (A) when pulling
|
|
** it out of the ephemeral table before calling VUpdate.
|
|
*/
|
|
static void updateVirtualTable(
|
|
Parse *pParse, /* The parsing context */
|
|
SrcList *pSrc, /* The virtual table to be modified */
|
|
Table *pTab, /* The virtual table */
|
|
ExprList *pChanges, /* The columns to change in the UPDATE statement */
|
|
Expr *pRowid, /* Expression used to recompute the rowid */
|
|
int *aXRef, /* Mapping from columns of pTab to entries in pChanges */
|
|
Expr *pWhere /* WHERE clause of the UPDATE statement */
|
|
){
|
|
Vdbe *v = pParse->pVdbe; /* Virtual machine under construction */
|
|
ExprList *pEList = 0; /* The result set of the SELECT statement */
|
|
Select *pSelect = 0; /* The SELECT statement */
|
|
Expr *pExpr; /* Temporary expression */
|
|
int ephemTab; /* Table holding the result of the SELECT */
|
|
int i; /* Loop counter */
|
|
int addr; /* Address of top of loop */
|
|
sqlite3 *db = pParse->db; /* Database connection */
|
|
|
|
/* Construct the SELECT statement that will find the new values for
|
|
** all updated rows.
|
|
*/
|
|
pEList = sqlite3ExprListAppend(pParse, 0,
|
|
sqlite3CreateIdExpr(pParse, "_rowid_"), 0);
|
|
if( pRowid ){
|
|
pEList = sqlite3ExprListAppend(pParse, pEList,
|
|
sqlite3ExprDup(db, pRowid), 0);
|
|
}
|
|
assert( pTab->iPKey<0 );
|
|
for(i=0; i<pTab->nCol; i++){
|
|
if( aXRef[i]>=0 ){
|
|
pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr);
|
|
}else{
|
|
pExpr = sqlite3CreateIdExpr(pParse, pTab->aCol[i].zName);
|
|
}
|
|
pEList = sqlite3ExprListAppend(pParse, pEList, pExpr, 0);
|
|
}
|
|
pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
|
|
|
|
/* Create the ephemeral table into which the update results will
|
|
** be stored.
|
|
*/
|
|
assert( v );
|
|
ephemTab = pParse->nTab++;
|
|
sqlite3VdbeAddOp(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
|
|
|
|
/* fill the ephemeral table
|
|
*/
|
|
sqlite3Select(pParse, pSelect, SRT_Table, ephemTab, 0, 0, 0, 0);
|
|
|
|
/*
|
|
** Generate code to scan the ephemeral table and call VDelete and
|
|
** VInsert
|
|
*/
|
|
sqlite3VdbeAddOp(v, OP_Rewind, ephemTab, 0);
|
|
addr = sqlite3VdbeCurrentAddr(v);
|
|
sqlite3VdbeAddOp(v, OP_Column, ephemTab, 0);
|
|
if( pRowid ){
|
|
sqlite3VdbeAddOp(v, OP_Column, ephemTab, 1);
|
|
}else{
|
|
sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
|
|
}
|
|
for(i=0; i<pTab->nCol; i++){
|
|
sqlite3VdbeAddOp(v, OP_Column, ephemTab, i+1+(pRowid!=0));
|
|
}
|
|
pParse->pVirtualLock = pTab;
|
|
sqlite3VdbeOp3(v, OP_VUpdate, 0, pTab->nCol+2,
|
|
(const char*)pTab->pVtab, P3_VTAB);
|
|
sqlite3VdbeAddOp(v, OP_Next, ephemTab, addr);
|
|
sqlite3VdbeJumpHere(v, addr-1);
|
|
sqlite3VdbeAddOp(v, OP_Close, ephemTab, 0);
|
|
|
|
/* Cleanup */
|
|
sqlite3SelectDelete(pSelect);
|
|
}
|
|
#endif /* SQLITE_OMIT_VIRTUALTABLE */
|