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Diffstat (limited to 'src/delete.c')
-rw-r--r-- | src/delete.c | 652 |
1 files changed, 652 insertions, 0 deletions
diff --git a/src/delete.c b/src/delete.c new file mode 100644 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; +} |