Import SQLite 3.10.2.

third_party/sqlite/src/src/delete.c

 /*
 ** 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.
 **
@@ skipping 88 matching lines @@
   int iDb = sqlite3SchemaToIndex(db, pView->pSchema);
   pWhere = sqlite3ExprDup(db, pWhere, 0);
   pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
   if( pFrom ){
     assert( pFrom->nSrc==1 );
     pFrom->a[0].zName = sqlite3DbStrDup(db, pView->zName);
     pFrom->a[0].zDatabase = sqlite3DbStrDup(db, db->aDb[iDb].zName);
     assert( pFrom->a[0].pOn==0 );
     assert( pFrom->a[0].pUsing==0 );
   }
-  pSel = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
+  pSel = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 
+                          SF_IncludeHidden, 0, 0);
   sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
   sqlite3Select(pParse, pSel, &dest);
   sqlite3SelectDelete(db, pSel);
 }
 #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.
@@ skipping 62 matching lines @@
   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);
+  sqlite3ExprSetHeightAndFlags(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);
@@ skipping 16 matching lines @@
   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 i;                 /* Loop counter */
   WhereInfo *pWInfo;     /* Information about the WHERE clause */
   Index *pIdx;           /* For looping over indices of the table */
   int iTabCur;           /* Cursor number for the table */
-  int iDataCur;          /* VDBE cursor for the canonical data source */
-  int iIdxCur;           /* Cursor number of the first index */
+  int iDataCur = 0;      /* VDBE cursor for the canonical data source */
+  int iIdxCur = 0;       /* Cursor number of the first index */
   int nIdx;              /* Number of indices */
   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 */
-  int okOnePass;         /* True for one-pass algorithm without the FIFO */
+  int eOnePass;          /* ONEPASS_OFF or _SINGLE or _MULTI */
   int aiCurOnePass[2];   /* The write cursors opened by WHERE_ONEPASS */
   u8 *aToOpen = 0;       /* Open cursor iTabCur+j if aToOpen[j] is true */
   Index *pPk;            /* The PRIMARY KEY index on the table */
   int iPk = 0;           /* First of nPk registers holding PRIMARY KEY value */
   i16 nPk = 1;           /* Number of columns in the PRIMARY KEY */
   int iKey;              /* Memory cell holding key of row to be deleted */
   i16 nKey;              /* Number of memory cells in the row key */
   int iEphCur = 0;       /* Ephemeral table holding all primary key values */
   int iRowSet = 0;       /* Register for rowset of rows to delete */
   int addrBypass = 0;    /* Address of jump over the delete logic */
   int addrLoop = 0;      /* Top of the delete loop */
-  int addrDelete = 0;    /* Jump directly to the delete logic */
   int addrEphOpen = 0;   /* Instruction to open the Ephemeral table */
  
 #ifndef SQLITE_OMIT_TRIGGER
   int isView;                  /* True if attempting to delete from a view */
   Trigger *pTrigger;           /* List of table triggers, if required */
+  int bComplex;                /* True if there are either triggers or FKs */
 #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;
+  bComplex = pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0);
 #else
 # define pTrigger 0
 # define isView 0
+# define bComplex 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;
@@ skipping 60 matching lines @@
   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)
+  if( rcauth==SQLITE_OK
+   && pWhere==0
+   && !bComplex
+   && !IsVirtual(pTab)
   ){
     assert( !isView );
     sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);
     if( HasRowid(pTab) ){
       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 */
   {
+    u16 wcf = WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK;
+    wcf |= (bComplex ? 0 : WHERE_ONEPASS_MULTIROW);
     if( HasRowid(pTab) ){
       /* For a rowid table, initialize the RowSet to an empty set */
       pPk = 0;
       nPk = 1;
       iRowSet = ++pParse->nMem;
       sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
     }else{
       /* For a WITHOUT ROWID table, create an ephemeral table used to
       ** hold all primary keys for rows to be deleted. */
       pPk = sqlite3PrimaryKeyIndex(pTab);
       assert( pPk!=0 );
       nPk = pPk->nKeyCol;
       iPk = pParse->nMem+1;
       pParse->nMem += nPk;
       iEphCur = pParse->nTab++;
       addrEphOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEphCur, nPk);
       sqlite3VdbeSetP4KeyInfo(pParse, pPk);
     }
   
     /* Construct a query to find the rowid or primary key for every row
-    ** to be deleted, based on the WHERE clause.
+    ** to be deleted, based on the WHERE clause. Set variable eOnePass
+    ** to indicate the strategy used to implement this delete:
+    **
+    **  ONEPASS_OFF:    Two-pass approach - use a FIFO for rowids/PK values.
+    **  ONEPASS_SINGLE: One-pass approach - at most one row deleted.
+    **  ONEPASS_MULTI:  One-pass approach - any number of rows may be deleted.
     */
-    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0, 
-                               WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK,
-                               iTabCur+1);
+    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0, wcf, iTabCur+1);
     if( pWInfo==0 ) goto delete_from_cleanup;
-    okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
+    eOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
+    assert( IsVirtual(pTab)==0 || eOnePass!=ONEPASS_MULTI );
+    assert( IsVirtual(pTab) || bComplex || eOnePass!=ONEPASS_OFF );
   
     /* Keep track of the number of rows to be deleted */
     if( db->flags & SQLITE_CountRows ){
       sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
     }
   
     /* Extract the rowid or primary key for the current row */
     if( pPk ){
       for(i=0; i<nPk; i++){
+        assert( pPk->aiColumn[i]>=0 );
         sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur,
                                         pPk->aiColumn[i], iPk+i);
       }
       iKey = iPk;
     }else{
       iKey = pParse->nMem + 1;
       iKey = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iTabCur, iKey, 0);
       if( iKey>pParse->nMem ) pParse->nMem = iKey;
     }
   
-    if( okOnePass ){
-      /* For ONEPASS, no need to store the rowid/primary-key.  There is only
+    if( eOnePass!=ONEPASS_OFF ){
+      /* For ONEPASS, no need to store the rowid/primary-key. There is only
       ** one, so just keep it in its register(s) and fall through to the
-      ** delete code.
-      */
+      ** delete code.  */
       nKey = nPk; /* OP_Found will use an unpacked key */
       aToOpen = sqlite3DbMallocRaw(db, nIdx+2);
       if( aToOpen==0 ){
         sqlite3WhereEnd(pWInfo);
         goto delete_from_cleanup;
       }
       memset(aToOpen, 1, nIdx+1);
       aToOpen[nIdx+1] = 0;
       if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iTabCur] = 0;
       if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iTabCur] = 0;
       if( addrEphOpen ) sqlite3VdbeChangeToNoop(v, addrEphOpen);
-      addrDelete = sqlite3VdbeAddOp0(v, OP_Goto); /* Jump to DELETE logic */
-    }else if( pPk ){
-      /* Construct a composite key for the row to be deleted and remember it */
-      iKey = ++pParse->nMem;
-      nKey = 0;   /* Zero tells OP_Found to use a composite key */
-      sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
-                        sqlite3IndexAffinityStr(v, pPk), nPk);
-      sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey);
     }else{
-      /* Get the rowid of the row to be deleted and remember it in the RowSet */
-      nKey = 1;  /* OP_Seek always uses a single rowid */
-      sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
+      if( pPk ){
+        /* Add the PK key for this row to the temporary table */
+        iKey = ++pParse->nMem;
+        nKey = 0;   /* Zero tells OP_Found to use a composite key */
+        sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
+            sqlite3IndexAffinityStr(pParse->db, pPk), nPk);
+        sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey);
+      }else{
+        /* Add the rowid of the row to be deleted to the RowSet */
+        nKey = 1;  /* OP_Seek always uses a single rowid */
+        sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
+      }
     }
   
-    /* End of the WHERE loop */
-    sqlite3WhereEnd(pWInfo);
-    if( okOnePass ){
-      /* Bypass the delete logic below if the WHERE loop found zero rows */
+    /* If this DELETE cannot use the ONEPASS strategy, this is the 
+    ** end of the WHERE loop */
+    if( eOnePass!=ONEPASS_OFF ){
       addrBypass = sqlite3VdbeMakeLabel(v);
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrBypass);
-      sqlite3VdbeJumpHere(v, addrDelete);
+    }else{
+      sqlite3WhereEnd(pWInfo);
     }
   
     /* 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 ){
+      int iAddrOnce = 0;
+      u8 p5 = (eOnePass==ONEPASS_OFF ? 0 : OPFLAG_FORDELETE);
+      if( eOnePass==ONEPASS_MULTI ){
+        iAddrOnce = sqlite3CodeOnce(pParse); VdbeCoverage(v);
+      }
       testcase( IsVirtual(pTab) );
-      sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, iTabCur, aToOpen,
-                                 &iDataCur, &iIdxCur);
+      sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, p5, iTabCur, 
+                                 aToOpen, &iDataCur, &iIdxCur);
       assert( pPk || IsVirtual(pTab) || iDataCur==iTabCur );
       assert( pPk || IsVirtual(pTab) || iIdxCur==iDataCur+1 );
+      if( eOnePass==ONEPASS_MULTI ) sqlite3VdbeJumpHere(v, iAddrOnce);
     }
   
     /* Set up a loop over the rowids/primary-keys that were found in the
     ** where-clause loop above.
     */
-    if( okOnePass ){
-      /* Just one row.  Hence the top-of-loop is a no-op */
+    if( eOnePass!=ONEPASS_OFF ){
       assert( nKey==nPk );  /* OP_Found will use an unpacked key */
-      assert( !IsVirtual(pTab) );
-      if( aToOpen[iDataCur-iTabCur] ){
+      if( !IsVirtual(pTab) && aToOpen[iDataCur-iTabCur] ){
         assert( pPk!=0 || pTab->pSelect!=0 );
         sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, addrBypass, iKey, nKey);
         VdbeCoverage(v);
       }
     }else if( pPk ){
       addrLoop = sqlite3VdbeAddOp1(v, OP_Rewind, iEphCur); VdbeCoverage(v);
       sqlite3VdbeAddOp2(v, OP_RowKey, iEphCur, iKey);
       assert( nKey==0 );  /* OP_Found will use a composite key */
     }else{
       addrLoop = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, 0, iKey);
       VdbeCoverage(v);
       assert( nKey==1 );
     }  
   
     /* 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, iKey, pVTab, P4_VTAB);
       sqlite3VdbeChangeP5(v, OE_Abort);
+      assert( eOnePass==ONEPASS_OFF || eOnePass==ONEPASS_SINGLE );
       sqlite3MayAbort(pParse);
+      if( eOnePass==ONEPASS_SINGLE && sqlite3IsToplevel(pParse) ){
+        pParse->isMultiWrite = 0;
+      }
     }else
 #endif
     {
       int count = (pParse->nested==0);    /* True to count changes */
+      int iIdxNoSeek = -1;
+      if( bComplex==0 && aiCurOnePass[1]!=iDataCur ){
+        iIdxNoSeek = aiCurOnePass[1];
+      }
       sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
-                               iKey, nKey, count, OE_Default, okOnePass);
+          iKey, nKey, count, OE_Default, eOnePass, iIdxNoSeek);
     }
   
     /* End of the loop over all rowids/primary-keys. */
-    if( okOnePass ){
+    if( eOnePass!=ONEPASS_OFF ){
       sqlite3VdbeResolveLabel(v, addrBypass);
+      sqlite3WhereEnd(pWInfo);
     }else if( pPk ){
       sqlite3VdbeAddOp2(v, OP_Next, iEphCur, addrLoop+1); VdbeCoverage(v);
       sqlite3VdbeJumpHere(v, addrLoop);
     }else{
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrLoop);
+      sqlite3VdbeGoto(v, addrLoop);
       sqlite3VdbeJumpHere(v, addrLoop);
     }     
   
     /* Close the cursors open on the table and its indexes. */
     if( !isView && !IsVirtual(pTab) ){
       if( !pPk ) sqlite3VdbeAddOp1(v, OP_Close, iDataCur);
       for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
         sqlite3VdbeAddOp1(v, OP_Close, iIdxCur + i);
       }
     }
@@ skipping 46 matching lines @@
 **       in the case of a rowid table, or the PRIMARY KEY index in the case
 **       of a WITHOUT ROWID table.)
 **
 **   2.  Read/write cursors for all indices of pTab must be open as
 **       cursor number iIdxCur+i for the i-th index.
 **
 **   3.  The primary key for the row to be deleted must be stored in a
 **       sequence of nPk memory cells starting at iPk.  If nPk==0 that means
 **       that a search record formed from OP_MakeRecord is contained in the
 **       single memory location iPk.
+**
+** eMode:
+**   Parameter eMode may be passed either ONEPASS_OFF (0), ONEPASS_SINGLE, or
+**   ONEPASS_MULTI.  If eMode is not ONEPASS_OFF, then the cursor
+**   iDataCur already points to the row to delete. If eMode is ONEPASS_OFF
+**   then this function must seek iDataCur to the entry identified by iPk
+**   and nPk before reading from it.
+**
+**   If eMode is ONEPASS_MULTI, then this call is being made as part
+**   of a ONEPASS delete that affects multiple rows. In this case, if 
+**   iIdxNoSeek is a valid cursor number (>=0), then its position should
+**   be preserved following the delete operation. Or, if iIdxNoSeek is not
+**   a valid cursor number, the position of iDataCur should be preserved
+**   instead.
+**
+** iIdxNoSeek:
+**   If iIdxNoSeek is a valid cursor number (>=0), then it identifies an
+**   index cursor (from within array of cursors starting at iIdxCur) that
+**   already points to the index entry to be deleted.
 */
 void sqlite3GenerateRowDelete(
   Parse *pParse,     /* Parsing context */
   Table *pTab,       /* Table containing the row to be deleted */
   Trigger *pTrigger, /* List of triggers to (potentially) fire */
   int iDataCur,      /* Cursor from which column data is extracted */
   int iIdxCur,       /* First index cursor */
   int iPk,           /* First memory cell containing the PRIMARY KEY */
   i16 nPk,           /* Number of PRIMARY KEY memory cells */
   u8 count,          /* If non-zero, increment the row change counter */
   u8 onconf,         /* Default ON CONFLICT policy for triggers */
-  u8 bNoSeek         /* iDataCur is already pointing to the row to delete */
+  u8 eMode,          /* ONEPASS_OFF, _SINGLE, or _MULTI.  See above */
+  int iIdxNoSeek     /* Cursor number of cursor that does not need seeking */
 ){
   Vdbe *v = pParse->pVdbe;        /* Vdbe */
   int iOld = 0;                   /* First register in OLD.* array */
   int iLabel;                     /* Label resolved to end of generated code */
   u8 opSeek;                      /* Seek opcode */
 
   /* Vdbe is guaranteed to have been allocated by this stage. */
   assert( v );
   VdbeModuleComment((v, "BEGIN: GenRowDel(%d,%d,%d,%d)",
                          iDataCur, iIdxCur, iPk, (int)nPk));
 
   /* 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);
   opSeek = HasRowid(pTab) ? OP_NotExists : OP_NotFound;
-  if( !bNoSeek ){
+  if( eMode==ONEPASS_OFF ){
     sqlite3VdbeAddOp4Int(v, opSeek, iDataCur, iLabel, iPk, nPk);
     VdbeCoverageIf(v, opSeek==OP_NotExists);
     VdbeCoverageIf(v, opSeek==OP_NotFound);
   }
  
   /* 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.* */
@@ skipping 39 matching lines @@
     /* 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, 0, 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, iDataCur, iIdxCur, 0);
+    sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur,0,iIdxNoSeek);
     sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, (count?OPFLAG_NCHANGE:0));
     if( count ){
       sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
     }
+    if( iIdxNoSeek>=0 ){
+      sqlite3VdbeAddOp1(v, OP_Delete, iIdxNoSeek);
+    }
+    sqlite3VdbeChangeP5(v, eMode==ONEPASS_MULTI);
   }
 
   /* 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, 0, 0);
 
   /* Invoke AFTER DELETE trigger programs. */
   sqlite3CodeRowTrigger(pParse, pTrigger, 
       TK_DELETE, 0, TRIGGER_AFTER, pTab, iOld, onconf, iLabel
@@ skipping 22 matching lines @@
 **       index is the 0-th index.)
 **
 **   3.  The "iDataCur" cursor must be already be positioned on 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 iDataCur,      /* Cursor of table holding data. */
   int iIdxCur,       /* First index cursor */
-  int *aRegIdx       /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
+  int *aRegIdx,      /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
+  int iIdxNoSeek     /* Do not delete from this cursor */
 ){
   int i;             /* Index loop counter */
   int r1 = -1;       /* Register holding an index key */
   int iPartIdxLabel; /* Jump destination for skipping partial index entries */
   Index *pIdx;       /* Current index */
   Index *pPrior = 0; /* Prior index */
   Vdbe *v;           /* The prepared statement under construction */
   Index *pPk;        /* PRIMARY KEY index, or NULL for rowid tables */
 
   v = pParse->pVdbe;
   pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
   for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
     assert( iIdxCur+i!=iDataCur || pPk==pIdx );
     if( aRegIdx!=0 && aRegIdx[i]==0 ) continue;
     if( pIdx==pPk ) continue;
+    if( iIdxCur+i==iIdxNoSeek ) continue;
     VdbeModuleComment((v, "GenRowIdxDel for %s", pIdx->zName));
     r1 = sqlite3GenerateIndexKey(pParse, pIdx, iDataCur, 0, 1,
-                                 &iPartIdxLabel, pPrior, r1);
+        &iPartIdxLabel, pPrior, r1);
     sqlite3VdbeAddOp3(v, OP_IdxDelete, iIdxCur+i, r1,
-                      pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn);
+        pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn);
     sqlite3ResolvePartIdxLabel(pParse, iPartIdxLabel);
     pPrior = pIdx;
   }
 }
 
 /*
 ** Generate code that will assemble an index key and stores 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.  If pTab is a WITHOUT ROWID table, then
@@ skipping 28 matching lines @@
   Index *pIdx,         /* The index for which to generate a key */
   int iDataCur,        /* Cursor number from which to take column data */
   int regOut,          /* Put the new key into this register if not 0 */
   int prefixOnly,      /* Compute only a unique prefix of the key */
   int *piPartIdxLabel, /* OUT: Jump to this label to skip partial index */
   Index *pPrior,       /* Previously generated index key */
   int regPrior         /* Register holding previous generated key */
 ){
   Vdbe *v = pParse->pVdbe;
   int j;
-  Table *pTab = pIdx->pTable;
   int regBase;
   int nCol;
 
   if( piPartIdxLabel ){
     if( pIdx->pPartIdxWhere ){
       *piPartIdxLabel = sqlite3VdbeMakeLabel(v);
-      pParse->iPartIdxTab = iDataCur;
+      pParse->iSelfTab = iDataCur;
       sqlite3ExprCachePush(pParse);
-      sqlite3ExprIfFalse(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel, 
-                         SQLITE_JUMPIFNULL);
+      sqlite3ExprIfFalseDup(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel, 
+                            SQLITE_JUMPIFNULL);
     }else{
       *piPartIdxLabel = 0;
     }
   }
   nCol = (prefixOnly && pIdx->uniqNotNull) ? pIdx->nKeyCol : pIdx->nColumn;
   regBase = sqlite3GetTempRange(pParse, nCol);
   if( pPrior && (regBase!=regPrior || pPrior->pPartIdxWhere) ) pPrior = 0;
   for(j=0; j<nCol; j++){
-    if( pPrior && pPrior->aiColumn[j]==pIdx->aiColumn[j] ) continue;
-    sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, pIdx->aiColumn[j],
-                                    regBase+j);
+    if( pPrior
+     && pPrior->aiColumn[j]==pIdx->aiColumn[j]
+     && pPrior->aiColumn[j]!=XN_EXPR
+    ){
+      /* This column was already computed by the previous index */
+      continue;
+    }
+    sqlite3ExprCodeLoadIndexColumn(pParse, pIdx, iDataCur, j, regBase+j);
     /* If the column affinity is REAL but the number is an integer, then it
     ** might be stored in the table as an integer (using a compact
     ** representation) then converted to REAL by an OP_RealAffinity opcode.
     ** But we are getting ready to store this value back into an index, where
     ** it should be converted by to INTEGER again.  So omit the OP_RealAffinity
     ** opcode if it is present */
     sqlite3VdbeDeletePriorOpcode(v, OP_RealAffinity);
   }
   if( regOut ){
     sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regOut);
   }
   sqlite3ReleaseTempRange(pParse, regBase, nCol);
   return regBase;
 }
 
 /*
 ** If a prior call to sqlite3GenerateIndexKey() generated a jump-over label
 ** because it was a partial index, then this routine should be called to
 ** resolve that label.
 */
 void sqlite3ResolvePartIdxLabel(Parse *pParse, int iLabel){
   if( iLabel ){
     sqlite3VdbeResolveLabel(pParse->pVdbe, iLabel);
     sqlite3ExprCachePop(pParse);
   }
 }