persistentstorage/sql/SQLite/delete.c
changeset 0 08ec8eefde2f
child 23 26645d81f48d
equal deleted inserted replaced
-1:000000000000 0:08ec8eefde2f
       
     1 /*
       
     2 ** 2001 September 15
       
     3 **
       
     4 ** The author disclaims copyright to this source code.  In place of
       
     5 ** a legal notice, here is a blessing:
       
     6 **
       
     7 **    May you do good and not evil.
       
     8 **    May you find forgiveness for yourself and forgive others.
       
     9 **    May you share freely, never taking more than you give.
       
    10 **
       
    11 *************************************************************************
       
    12 ** This file contains C code routines that are called by the parser
       
    13 ** in order to generate code for DELETE FROM statements.
       
    14 **
       
    15 ** $Id: delete.c,v 1.171 2008/07/28 19:34:53 drh Exp $
       
    16 */
       
    17 #include "sqliteInt.h"
       
    18 
       
    19 /*
       
    20 ** Look up every table that is named in pSrc.  If any table is not found,
       
    21 ** add an error message to pParse->zErrMsg and return NULL.  If all tables
       
    22 ** are found, return a pointer to the last table.
       
    23 */
       
    24 Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
       
    25   Table *pTab = 0;
       
    26   int i;
       
    27   struct SrcList_item *pItem;
       
    28   for(i=0, pItem=pSrc->a; i<pSrc->nSrc; i++, pItem++){
       
    29     pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
       
    30     sqlite3DeleteTable(pItem->pTab);
       
    31     pItem->pTab = pTab;
       
    32     if( pTab ){
       
    33       pTab->nRef++;
       
    34     }
       
    35   }
       
    36   return pTab;
       
    37 }
       
    38 
       
    39 /*
       
    40 ** Check to make sure the given table is writable.  If it is not
       
    41 ** writable, generate an error message and return 1.  If it is
       
    42 ** writable return 0;
       
    43 */
       
    44 int sqlite3IsReadOnly(Parse *pParse, Table *pTab, int viewOk){
       
    45   if( (pTab->readOnly && (pParse->db->flags & SQLITE_WriteSchema)==0
       
    46         && pParse->nested==0) 
       
    47 #ifndef SQLITE_OMIT_VIRTUALTABLE
       
    48       || (pTab->pMod && pTab->pMod->pModule->xUpdate==0)
       
    49 #endif
       
    50   ){
       
    51     sqlite3ErrorMsg(pParse, "table %s may not be modified", pTab->zName);
       
    52     return 1;
       
    53   }
       
    54 #ifndef SQLITE_OMIT_VIEW
       
    55   if( !viewOk && pTab->pSelect ){
       
    56     sqlite3ErrorMsg(pParse,"cannot modify %s because it is a view",pTab->zName);
       
    57     return 1;
       
    58   }
       
    59 #endif
       
    60   return 0;
       
    61 }
       
    62 
       
    63 /*
       
    64 ** Generate code that will open a table for reading.
       
    65 */
       
    66 void sqlite3OpenTable(
       
    67   Parse *p,       /* Generate code into this VDBE */
       
    68   int iCur,       /* The cursor number of the table */
       
    69   int iDb,        /* The database index in sqlite3.aDb[] */
       
    70   Table *pTab,    /* The table to be opened */
       
    71   int opcode      /* OP_OpenRead or OP_OpenWrite */
       
    72 ){
       
    73   Vdbe *v;
       
    74   if( IsVirtual(pTab) ) return;
       
    75   v = sqlite3GetVdbe(p);
       
    76   assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
       
    77   sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite), pTab->zName);
       
    78   sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
       
    79   sqlite3VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb);
       
    80   VdbeComment((v, "%s", pTab->zName));
       
    81 }
       
    82 
       
    83 
       
    84 #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
       
    85 /*
       
    86 ** Evaluate a view and store its result in an ephemeral table.  The
       
    87 ** pWhere argument is an optional WHERE clause that restricts the
       
    88 ** set of rows in the view that are to be added to the ephemeral table.
       
    89 */
       
    90 void sqlite3MaterializeView(
       
    91   Parse *pParse,       /* Parsing context */
       
    92   Select *pView,       /* View definition */
       
    93   Expr *pWhere,        /* Optional WHERE clause to be added */
       
    94   int iCur             /* Cursor number for ephemerial table */
       
    95 ){
       
    96   SelectDest dest;
       
    97   Select *pDup;
       
    98   sqlite3 *db = pParse->db;
       
    99 
       
   100   pDup = sqlite3SelectDup(db, pView);
       
   101   if( pWhere ){
       
   102     SrcList *pFrom;
       
   103     
       
   104     pWhere = sqlite3ExprDup(db, pWhere);
       
   105     pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, 0, pDup, 0, 0);
       
   106     pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
       
   107   }
       
   108   sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
       
   109   sqlite3Select(pParse, pDup, &dest, 0, 0, 0);
       
   110   sqlite3SelectDelete(db, pDup);
       
   111 }
       
   112 #endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */
       
   113 
       
   114 
       
   115 /*
       
   116 ** Generate code for a DELETE FROM statement.
       
   117 **
       
   118 **     DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
       
   119 **                 \________/       \________________/
       
   120 **                  pTabList              pWhere
       
   121 */
       
   122 void sqlite3DeleteFrom(
       
   123   Parse *pParse,         /* The parser context */
       
   124   SrcList *pTabList,     /* The table from which we should delete things */
       
   125   Expr *pWhere           /* The WHERE clause.  May be null */
       
   126 ){
       
   127   Vdbe *v;               /* The virtual database engine */
       
   128   Table *pTab;           /* The table from which records will be deleted */
       
   129   const char *zDb;       /* Name of database holding pTab */
       
   130   int end, addr = 0;     /* A couple addresses of generated code */
       
   131   int i;                 /* Loop counter */
       
   132   WhereInfo *pWInfo;     /* Information about the WHERE clause */
       
   133   Index *pIdx;           /* For looping over indices of the table */
       
   134   int iCur;              /* VDBE Cursor number for pTab */
       
   135   sqlite3 *db;           /* Main database structure */
       
   136   AuthContext sContext;  /* Authorization context */
       
   137   int oldIdx = -1;       /* Cursor for the OLD table of AFTER triggers */
       
   138   NameContext sNC;       /* Name context to resolve expressions in */
       
   139   int iDb;               /* Database number */
       
   140   int memCnt = 0;        /* Memory cell used for change counting */
       
   141 
       
   142 #ifndef SQLITE_OMIT_TRIGGER
       
   143   int isView;                  /* True if attempting to delete from a view */
       
   144   int triggers_exist = 0;      /* True if any triggers exist */
       
   145 #endif
       
   146   int iBeginAfterTrigger;      /* Address of after trigger program */
       
   147   int iEndAfterTrigger;        /* Exit of after trigger program */
       
   148   int iBeginBeforeTrigger;     /* Address of before trigger program */
       
   149   int iEndBeforeTrigger;       /* Exit of before trigger program */
       
   150   u32 old_col_mask = 0;        /* Mask of OLD.* columns in use */
       
   151 
       
   152   sContext.pParse = 0;
       
   153   db = pParse->db;
       
   154   if( pParse->nErr || db->mallocFailed ){
       
   155     goto delete_from_cleanup;
       
   156   }
       
   157   assert( pTabList->nSrc==1 );
       
   158 
       
   159   /* Locate the table which we want to delete.  This table has to be
       
   160   ** put in an SrcList structure because some of the subroutines we
       
   161   ** will be calling are designed to work with multiple tables and expect
       
   162   ** an SrcList* parameter instead of just a Table* parameter.
       
   163   */
       
   164   pTab = sqlite3SrcListLookup(pParse, pTabList);
       
   165   if( pTab==0 )  goto delete_from_cleanup;
       
   166 
       
   167   /* Figure out if we have any triggers and if the table being
       
   168   ** deleted from is a view
       
   169   */
       
   170 #ifndef SQLITE_OMIT_TRIGGER
       
   171   triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0);
       
   172   isView = pTab->pSelect!=0;
       
   173 #else
       
   174 # define triggers_exist 0
       
   175 # define isView 0
       
   176 #endif
       
   177 #ifdef SQLITE_OMIT_VIEW
       
   178 # undef isView
       
   179 # define isView 0
       
   180 #endif
       
   181 
       
   182   if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
       
   183     goto delete_from_cleanup;
       
   184   }
       
   185   iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
       
   186   assert( iDb<db->nDb );
       
   187   zDb = db->aDb[iDb].zName;
       
   188   if( sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb) ){
       
   189     goto delete_from_cleanup;
       
   190   }
       
   191 
       
   192   /* If pTab is really a view, make sure it has been initialized.
       
   193   */
       
   194   if( sqlite3ViewGetColumnNames(pParse, pTab) ){
       
   195     goto delete_from_cleanup;
       
   196   }
       
   197 
       
   198   /* Allocate a cursor used to store the old.* data for a trigger.
       
   199   */
       
   200   if( triggers_exist ){ 
       
   201     oldIdx = pParse->nTab++;
       
   202   }
       
   203 
       
   204   /* Assign  cursor number to the table and all its indices.
       
   205   */
       
   206   assert( pTabList->nSrc==1 );
       
   207   iCur = pTabList->a[0].iCursor = pParse->nTab++;
       
   208   for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
       
   209     pParse->nTab++;
       
   210   }
       
   211 
       
   212   /* Start the view context
       
   213   */
       
   214   if( isView ){
       
   215     sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
       
   216   }
       
   217 
       
   218   /* Begin generating code.
       
   219   */
       
   220   v = sqlite3GetVdbe(pParse);
       
   221   if( v==0 ){
       
   222     goto delete_from_cleanup;
       
   223   }
       
   224   if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
       
   225   sqlite3BeginWriteOperation(pParse, triggers_exist, iDb);
       
   226 
       
   227   if( triggers_exist ){
       
   228     int orconf = ((pParse->trigStack)?pParse->trigStack->orconf:OE_Default);
       
   229     int iGoto = sqlite3VdbeAddOp0(v, OP_Goto);
       
   230     addr = sqlite3VdbeMakeLabel(v);
       
   231 
       
   232     iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
       
   233     (void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_BEFORE, pTab,
       
   234         -1, oldIdx, orconf, addr, &old_col_mask, 0);
       
   235     iEndBeforeTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
       
   236 
       
   237     iBeginAfterTrigger = sqlite3VdbeCurrentAddr(v);
       
   238     (void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_AFTER, pTab, -1,
       
   239         oldIdx, orconf, addr, &old_col_mask, 0);
       
   240     iEndAfterTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
       
   241 
       
   242     sqlite3VdbeJumpHere(v, iGoto);
       
   243   }
       
   244 
       
   245   /* If we are trying to delete from a view, realize that view into
       
   246   ** a ephemeral table.
       
   247   */
       
   248   if( isView ){
       
   249     sqlite3MaterializeView(pParse, pTab->pSelect, pWhere, iCur);
       
   250   }
       
   251 
       
   252   /* Resolve the column names in the WHERE clause.
       
   253   */
       
   254   memset(&sNC, 0, sizeof(sNC));
       
   255   sNC.pParse = pParse;
       
   256   sNC.pSrcList = pTabList;
       
   257   if( sqlite3ExprResolveNames(&sNC, pWhere) ){
       
   258     goto delete_from_cleanup;
       
   259   }
       
   260 
       
   261   /* Initialize the counter of the number of rows deleted, if
       
   262   ** we are counting rows.
       
   263   */
       
   264   if( db->flags & SQLITE_CountRows ){
       
   265     memCnt = ++pParse->nMem;
       
   266     sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
       
   267   }
       
   268 
       
   269   /* Special case: A DELETE without a WHERE clause deletes everything.
       
   270   ** It is easier just to erase the whole table.  Note, however, that
       
   271   ** this means that the row change count will be incorrect.
       
   272   */
       
   273   if( pWhere==0 && !triggers_exist && !IsVirtual(pTab) ){
       
   274     if( db->flags & SQLITE_CountRows ){
       
   275       /* If counting rows deleted, just count the total number of
       
   276       ** entries in the table. */
       
   277       int addr2;
       
   278       if( !isView ){
       
   279         sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
       
   280       }
       
   281       sqlite3VdbeAddOp2(v, OP_Rewind, iCur, sqlite3VdbeCurrentAddr(v)+2);
       
   282       addr2 = sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
       
   283       sqlite3VdbeAddOp2(v, OP_Next, iCur, addr2);
       
   284       sqlite3VdbeAddOp1(v, OP_Close, iCur);
       
   285     }
       
   286     if( !isView ){
       
   287       sqlite3VdbeAddOp2(v, OP_Clear, pTab->tnum, iDb);
       
   288       if( !pParse->nested ){
       
   289         sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
       
   290       }
       
   291       for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
       
   292         assert( pIdx->pSchema==pTab->pSchema );
       
   293         sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
       
   294       }
       
   295     }
       
   296   } 
       
   297   /* The usual case: There is a WHERE clause so we have to scan through
       
   298   ** the table and pick which records to delete.
       
   299   */
       
   300   else{
       
   301     int iRowid = ++pParse->nMem;    /* Used for storing rowid values. */
       
   302 
       
   303     /* Begin the database scan
       
   304     */
       
   305     pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
       
   306     if( pWInfo==0 ) goto delete_from_cleanup;
       
   307 
       
   308     /* Remember the rowid of every item to be deleted.
       
   309     */
       
   310     sqlite3VdbeAddOp2(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid, iCur, iRowid);
       
   311     sqlite3VdbeAddOp1(v, OP_FifoWrite, iRowid);
       
   312     if( db->flags & SQLITE_CountRows ){
       
   313       sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
       
   314     }
       
   315 
       
   316     /* End the database scan loop.
       
   317     */
       
   318     sqlite3WhereEnd(pWInfo);
       
   319 
       
   320     /* Open the pseudo-table used to store OLD if there are triggers.
       
   321     */
       
   322     if( triggers_exist ){
       
   323       sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
       
   324       sqlite3VdbeAddOp1(v, OP_OpenPseudo, oldIdx);
       
   325     }
       
   326 
       
   327     /* Delete every item whose key was written to the list during the
       
   328     ** database scan.  We have to delete items after the scan is complete
       
   329     ** because deleting an item can change the scan order.
       
   330     */
       
   331     end = sqlite3VdbeMakeLabel(v);
       
   332 
       
   333     if( !isView ){
       
   334       /* Open cursors for the table we are deleting from and 
       
   335       ** all its indices.
       
   336       */
       
   337       sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
       
   338     }
       
   339 
       
   340     /* This is the beginning of the delete loop. If a trigger encounters
       
   341     ** an IGNORE constraint, it jumps back to here.
       
   342     */
       
   343     if( triggers_exist ){
       
   344       sqlite3VdbeResolveLabel(v, addr);
       
   345     }
       
   346     addr = sqlite3VdbeAddOp2(v, OP_FifoRead, iRowid, end);
       
   347 
       
   348     if( triggers_exist ){
       
   349       int iData = ++pParse->nMem;   /* For storing row data of OLD table */
       
   350 
       
   351       /* If the record is no longer present in the table, jump to the
       
   352       ** next iteration of the loop through the contents of the fifo.
       
   353       */
       
   354       sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, iRowid);
       
   355 
       
   356       /* Populate the OLD.* pseudo-table */
       
   357       if( old_col_mask ){
       
   358         sqlite3VdbeAddOp2(v, OP_RowData, iCur, iData);
       
   359       }else{
       
   360         sqlite3VdbeAddOp2(v, OP_Null, 0, iData);
       
   361       }
       
   362       sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, iData, iRowid);
       
   363 
       
   364       /* Jump back and run the BEFORE triggers */
       
   365       sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
       
   366       sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
       
   367     }
       
   368 
       
   369     if( !isView ){
       
   370       /* Delete the row */
       
   371 #ifndef SQLITE_OMIT_VIRTUALTABLE
       
   372       if( IsVirtual(pTab) ){
       
   373         const char *pVtab = (const char *)pTab->pVtab;
       
   374         sqlite3VtabMakeWritable(pParse, pTab);
       
   375         sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVtab, P4_VTAB);
       
   376       }else
       
   377 #endif
       
   378       {
       
   379         sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, pParse->nested==0);
       
   380       }
       
   381     }
       
   382 
       
   383     /* If there are row triggers, close all cursors then invoke
       
   384     ** the AFTER triggers
       
   385     */
       
   386     if( triggers_exist ){
       
   387       /* Jump back and run the AFTER triggers */
       
   388       sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
       
   389       sqlite3VdbeJumpHere(v, iEndAfterTrigger);
       
   390     }
       
   391 
       
   392     /* End of the delete loop */
       
   393     sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
       
   394     sqlite3VdbeResolveLabel(v, end);
       
   395 
       
   396     /* Close the cursors after the loop if there are no row triggers */
       
   397     if( !isView  && !IsVirtual(pTab) ){
       
   398       for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
       
   399         sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
       
   400       }
       
   401       sqlite3VdbeAddOp1(v, OP_Close, iCur);
       
   402     }
       
   403   }
       
   404 
       
   405   /*
       
   406   ** Return the number of rows that were deleted. If this routine is 
       
   407   ** generating code because of a call to sqlite3NestedParse(), do not
       
   408   ** invoke the callback function.
       
   409   */
       
   410   if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){
       
   411     sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
       
   412     sqlite3VdbeSetNumCols(v, 1);
       
   413     sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", P4_STATIC);
       
   414   }
       
   415 
       
   416 delete_from_cleanup:
       
   417   sqlite3AuthContextPop(&sContext);
       
   418   sqlite3SrcListDelete(db, pTabList);
       
   419   sqlite3ExprDelete(db, pWhere);
       
   420   return;
       
   421 }
       
   422 
       
   423 /*
       
   424 ** This routine generates VDBE code that causes a single row of a
       
   425 ** single table to be deleted.
       
   426 **
       
   427 ** The VDBE must be in a particular state when this routine is called.
       
   428 ** These are the requirements:
       
   429 **
       
   430 **   1.  A read/write cursor pointing to pTab, the table containing the row
       
   431 **       to be deleted, must be opened as cursor number "base".
       
   432 **
       
   433 **   2.  Read/write cursors for all indices of pTab must be open as
       
   434 **       cursor number base+i for the i-th index.
       
   435 **
       
   436 **   3.  The record number of the row to be deleted must be stored in
       
   437 **       memory cell iRowid.
       
   438 **
       
   439 ** This routine pops the top of the stack to remove the record number
       
   440 ** and then generates code to remove both the table record and all index
       
   441 ** entries that point to that record.
       
   442 */
       
   443 void sqlite3GenerateRowDelete(
       
   444   Parse *pParse,     /* Parsing context */
       
   445   Table *pTab,       /* Table containing the row to be deleted */
       
   446   int iCur,          /* Cursor number for the table */
       
   447   int iRowid,        /* Memory cell that contains the rowid to delete */
       
   448   int count          /* Increment the row change counter */
       
   449 ){
       
   450   int addr;
       
   451   Vdbe *v;
       
   452 
       
   453   v = pParse->pVdbe;
       
   454   addr = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, iRowid);
       
   455   sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
       
   456   sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
       
   457   if( count ){
       
   458     sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
       
   459   }
       
   460   sqlite3VdbeJumpHere(v, addr);
       
   461 }
       
   462 
       
   463 /*
       
   464 ** This routine generates VDBE code that causes the deletion of all
       
   465 ** index entries associated with a single row of a single table.
       
   466 **
       
   467 ** The VDBE must be in a particular state when this routine is called.
       
   468 ** These are the requirements:
       
   469 **
       
   470 **   1.  A read/write cursor pointing to pTab, the table containing the row
       
   471 **       to be deleted, must be opened as cursor number "iCur".
       
   472 **
       
   473 **   2.  Read/write cursors for all indices of pTab must be open as
       
   474 **       cursor number iCur+i for the i-th index.
       
   475 **
       
   476 **   3.  The "iCur" cursor must be pointing to the row that is to be
       
   477 **       deleted.
       
   478 */
       
   479 void sqlite3GenerateRowIndexDelete(
       
   480   Parse *pParse,     /* Parsing and code generating context */
       
   481   Table *pTab,       /* Table containing the row to be deleted */
       
   482   int iCur,          /* Cursor number for the table */
       
   483   int *aRegIdx       /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
       
   484 ){
       
   485   int i;
       
   486   Index *pIdx;
       
   487   int r1;
       
   488 
       
   489   for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
       
   490     if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
       
   491     r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
       
   492     sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
       
   493   }
       
   494 }
       
   495 
       
   496 /*
       
   497 ** Generate code that will assemble an index key and put it in register
       
   498 ** regOut.  The key with be for index pIdx which is an index on pTab.
       
   499 ** iCur is the index of a cursor open on the pTab table and pointing to
       
   500 ** the entry that needs indexing.
       
   501 **
       
   502 ** Return a register number which is the first in a block of
       
   503 ** registers that holds the elements of the index key.  The
       
   504 ** block of registers has already been deallocated by the time
       
   505 ** this routine returns.
       
   506 */
       
   507 int sqlite3GenerateIndexKey(
       
   508   Parse *pParse,     /* Parsing context */
       
   509   Index *pIdx,       /* The index for which to generate a key */
       
   510   int iCur,          /* Cursor number for the pIdx->pTable table */
       
   511   int regOut,        /* Write the new index key to this register */
       
   512   int doMakeRec      /* Run the OP_MakeRecord instruction if true */
       
   513 ){
       
   514   Vdbe *v = pParse->pVdbe;
       
   515   int j;
       
   516   Table *pTab = pIdx->pTable;
       
   517   int regBase;
       
   518   int nCol;
       
   519 
       
   520   nCol = pIdx->nColumn;
       
   521   regBase = sqlite3GetTempRange(pParse, nCol+1);
       
   522   sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
       
   523   for(j=0; j<nCol; j++){
       
   524     int idx = pIdx->aiColumn[j];
       
   525     if( idx==pTab->iPKey ){
       
   526       sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);
       
   527     }else{
       
   528       sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);
       
   529       sqlite3ColumnDefault(v, pTab, idx);
       
   530     }
       
   531   }
       
   532   if( doMakeRec ){
       
   533     sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
       
   534     sqlite3IndexAffinityStr(v, pIdx);
       
   535     sqlite3ExprCacheAffinityChange(pParse, regBase, nCol+1);
       
   536   }
       
   537   sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
       
   538   return regBase;
       
   539 }
       
   540 
       
   541 /* Make sure "isView" gets undefined in case this file becomes part of
       
   542 ** the amalgamation - so that subsequent files do not see isView as a
       
   543 ** macro. */
       
   544 #undef isView