[sql] Import reference version of SQLite 3.10.2.

third_party/sqlite/sqlite-src-3100200/src/fkey.c

 /*
 **
 ** 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 231 matching lines @@
           break;
         }
       }else{
         /* If zKey is non-NULL, then this foreign key was declared to
         ** map to an explicit list of columns in table pParent. Check if this
         ** index matches those columns. Also, check that the index uses
         ** the default collation sequences for each column. */
         int i, j;
         for(i=0; i<nCol; i++){
           i16 iCol = pIdx->aiColumn[i];     /* Index of column in parent tbl */
-          char *zDfltColl;                  /* Def. collation for column */
+          const char *zDfltColl;            /* Def. collation for column */
           char *zIdxCol;                    /* Name of indexed column */
 
+          if( iCol<0 ) break; /* No foreign keys against expression indexes */
+
           /* If the index uses a collation sequence that is different from
           ** the default collation sequence for the column, this index is
           ** unusable. Bail out early in this case.  */
           zDfltColl = pParent->aCol[iCol].zColl;
-          if( !zDfltColl ){
-            zDfltColl = "BINARY";
-          }
+          if( !zDfltColl ) zDfltColl = sqlite3StrBINARY;
           if( sqlite3StrICmp(pIdx->azColl[i], zDfltColl) ) break;
 
           zIdxCol = pParent->aCol[iCol].zName;
           for(j=0; j<nCol; j++){
             if( sqlite3StrICmp(pFKey->aCol[j].zCol, zIdxCol)==0 ){
               if( aiCol ) aiCol[i] = pFKey->aCol[j].iFrom;
               break;
             }
           }
           if( j==nCol ) break;
@@ skipping 95 matching lines @@
       ** to increment the constraint-counter (i.e. this is an INSERT operation),
       ** then check if the row being inserted matches itself. If so, do not
       ** increment the constraint-counter.  */
       if( pTab==pFKey->pFrom && nIncr==1 ){
         sqlite3VdbeAddOp3(v, OP_Eq, regData, iOk, regTemp); VdbeCoverage(v);
         sqlite3VdbeChangeP5(v, SQLITE_NOTNULL);
       }
   
       sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
       sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regTemp); VdbeCoverage(v);
-      sqlite3VdbeAddOp2(v, OP_Goto, 0, iOk);
+      sqlite3VdbeGoto(v, iOk);
       sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);
       sqlite3VdbeJumpHere(v, iMustBeInt);
       sqlite3ReleaseTempReg(pParse, regTemp);
     }else{
       int nCol = pFKey->nCol;
       int regTemp = sqlite3GetTempRange(pParse, nCol);
       int regRec = sqlite3GetTempReg(pParse);
   
       sqlite3VdbeAddOp3(v, OP_OpenRead, iCur, pIdx->tnum, iDb);
       sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
       for(i=0; i<nCol; i++){
         sqlite3VdbeAddOp2(v, OP_Copy, aiCol[i]+1+regData, regTemp+i);
       }
   
       /* If the parent table is the same as the child table, and we are about
       ** to increment the constraint-counter (i.e. this is an INSERT operation),
       ** then check if the row being inserted matches itself. If so, do not
       ** increment the constraint-counter. 
       **
       ** If any of the parent-key values are NULL, then the row cannot match 
       ** itself. So set JUMPIFNULL to make sure we do the OP_Found if any
       ** of the parent-key values are NULL (at this point it is known that
       ** none of the child key values are).
       */
       if( pTab==pFKey->pFrom && nIncr==1 ){
         int iJump = sqlite3VdbeCurrentAddr(v) + nCol + 1;
         for(i=0; i<nCol; i++){
           int iChild = aiCol[i]+1+regData;
           int iParent = pIdx->aiColumn[i]+1+regData;
+          assert( pIdx->aiColumn[i]>=0 );
           assert( aiCol[i]!=pTab->iPKey );
           if( pIdx->aiColumn[i]==pTab->iPKey ){
             /* The parent key is a composite key that includes the IPK column */
             iParent = regData;
           }
           sqlite3VdbeAddOp3(v, OP_Ne, iChild, iJump, iParent); VdbeCoverage(v);
           sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
         }
-        sqlite3VdbeAddOp2(v, OP_Goto, 0, iOk);
+        sqlite3VdbeGoto(v, iOk);
       }
   
       sqlite3VdbeAddOp4(v, OP_MakeRecord, regTemp, nCol, regRec,
-                        sqlite3IndexAffinityStr(v,pIdx), nCol);
+                        sqlite3IndexAffinityStr(pParse->db,pIdx), nCol);
       sqlite3VdbeAddOp4Int(v, OP_Found, iCur, iOk, regRec, 0); VdbeCoverage(v);
   
       sqlite3ReleaseTempReg(pParse, regRec);
       sqlite3ReleaseTempRange(pParse, regTemp, nCol);
     }
   }
 
   if( !pFKey->isDeferred && !(pParse->db->flags & SQLITE_DeferFKs)
    && !pParse->pToplevel 
    && !pParse->isMultiWrite 
   ){
     /* Special case: If this is an INSERT statement that will insert exactly
     ** one row into the table, raise a constraint immediately instead of
     ** incrementing a counter. This is necessary as the VM code is being
     ** generated for will not open a statement transaction.  */
     assert( nIncr==1 );
     sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_FOREIGNKEY,
         OE_Abort, 0, P4_STATIC, P5_ConstraintFK);
   }else{
     if( nIncr>0 && pFKey->isDeferred==0 ){
-      sqlite3ParseToplevel(pParse)->mayAbort = 1;
+      sqlite3MayAbort(pParse);
     }
     sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, nIncr);
   }
 
   sqlite3VdbeResolveLabel(v, iOk);
   sqlite3VdbeAddOp1(v, OP_Close, iCur);
 }
 
 
 /*
@@ skipping 51 matching lines @@
   return pExpr;
 }
 
 /*
 ** This function is called to generate code executed when a row is deleted
 ** from the parent table of foreign key constraint pFKey and, if pFKey is 
 ** deferred, when a row is inserted into the same table. When generating
 ** code for an SQL UPDATE operation, this function may be called twice -
 ** once to "delete" the old row and once to "insert" the new row.
 **
+** Parameter nIncr is passed -1 when inserting a row (as this may decrease
+** the number of FK violations in the db) or +1 when deleting one (as this
+** may increase the number of FK constraint problems).
+**
 ** The code generated by this function scans through the rows in the child
 ** table that correspond to the parent table row being deleted or inserted.
 ** For each child row found, one of the following actions is taken:
 **
 **   Operation | FK type   | Action taken
 **   --------------------------------------------------------------------------
 **   DELETE      immediate   Increment the "immediate constraint counter".
 **                           Or, if the ON (UPDATE|DELETE) action is RESTRICT,
 **                           throw a "FOREIGN KEY constraint failed" exception.
 **
@@ skipping 79 matching lines @@
     if( HasRowid(pTab) ){
       pLeft = exprTableRegister(pParse, pTab, regData, -1);
       pRight = exprTableColumn(db, pTab, pSrc->a[0].iCursor, -1);
       pNe = sqlite3PExpr(pParse, TK_NE, pLeft, pRight, 0);
     }else{
       Expr *pEq, *pAll = 0;
       Index *pPk = sqlite3PrimaryKeyIndex(pTab);
       assert( pIdx!=0 );
       for(i=0; i<pPk->nKeyCol; i++){
         i16 iCol = pIdx->aiColumn[i];
+        assert( iCol>=0 );
         pLeft = exprTableRegister(pParse, pTab, regData, iCol);
         pRight = exprTableColumn(db, pTab, pSrc->a[0].iCursor, iCol);
         pEq = sqlite3PExpr(pParse, TK_EQ, pLeft, pRight, 0);
         pAll = sqlite3ExprAnd(db, pAll, pEq);
       }
       pNe = sqlite3PExpr(pParse, TK_NOT, pAll, 0, 0);
     }
     pWhere = sqlite3ExprAnd(db, pWhere, pNe);
   }
 
   /* Resolve the references in the WHERE clause. */
   memset(&sNameContext, 0, sizeof(NameContext));
   sNameContext.pSrcList = pSrc;
   sNameContext.pParse = pParse;
   sqlite3ResolveExprNames(&sNameContext, pWhere);
 
   /* Create VDBE to loop through the entries in pSrc that match the WHERE
-  ** clause. If the constraint is not deferred, throw an exception for
-  ** each row found. Otherwise, for deferred constraints, increment the
-  ** deferred constraint counter by nIncr for each row selected.  */
+  ** clause. For each row found, increment either the deferred or immediate
+  ** foreign key constraint counter. */
   pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0, 0, 0);
-  if( nIncr>0 && pFKey->isDeferred==0 ){
-    sqlite3ParseToplevel(pParse)->mayAbort = 1;
-  }
   sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, nIncr);
   if( pWInfo ){
     sqlite3WhereEnd(pWInfo);
   }
 
   /* Clean up the WHERE clause constructed above. */
   sqlite3ExprDelete(db, pWhere);
   if( iFkIfZero ){
     sqlite3VdbeJumpHere(v, iFkIfZero);
   }
@@ skipping 159 matching lines @@
         }else if( pCol->colFlags & COLFLAG_PRIMKEY ){
           return 1;
         }
       }
     }
   }
   return 0;
 }
 
 /*
+** Return true if the parser passed as the first argument is being
+** used to code a trigger that is really a "SET NULL" action belonging
+** to trigger pFKey.
+*/
+static int isSetNullAction(Parse *pParse, FKey *pFKey){
+  Parse *pTop = sqlite3ParseToplevel(pParse);
+  if( pTop->pTriggerPrg ){
+    Trigger *p = pTop->pTriggerPrg->pTrigger;
+    if( (p==pFKey->apTrigger[0] && pFKey->aAction[0]==OE_SetNull)
+     || (p==pFKey->apTrigger[1] && pFKey->aAction[1]==OE_SetNull)
+    ){
+      return 1;
+    }
+  }
+  return 0;
+}
+
+/*
 ** This function is called when inserting, deleting or updating a row of
 ** table pTab to generate VDBE code to perform foreign key constraint 
 ** processing for the operation.
 **
 ** For a DELETE operation, parameter regOld is passed the index of the
 ** first register in an array of (pTab->nCol+1) registers containing the
 ** rowid of the row being deleted, followed by each of the column values
 ** of the row being deleted, from left to right. Parameter regNew is passed
 ** zero in this case.
 **
@@ skipping 31 matching lines @@
 
   /* Loop through all the foreign key constraints for which pTab is the
   ** child table (the table that the foreign key definition is part of).  */
   for(pFKey=pTab->pFKey; pFKey; pFKey=pFKey->pNextFrom){
     Table *pTo;                   /* Parent table of foreign key pFKey */
     Index *pIdx = 0;              /* Index on key columns in pTo */
     int *aiFree = 0;
     int *aiCol;
     int iCol;
     int i;
-    int isIgnore = 0;
+    int bIgnore = 0;
 
     if( aChange 
      && sqlite3_stricmp(pTab->zName, pFKey->zTo)!=0
      && fkChildIsModified(pTab, pFKey, aChange, bChngRowid)==0 
     ){
       continue;
     }
 
     /* Find the parent table of this foreign key. Also find a unique index 
     ** on the parent key columns in the parent table. If either of these 
@@ skipping 30 matching lines @@
     if( aiFree ){
       aiCol = aiFree;
     }else{
       iCol = pFKey->aCol[0].iFrom;
       aiCol = &iCol;
     }
     for(i=0; i<pFKey->nCol; i++){
       if( aiCol[i]==pTab->iPKey ){
         aiCol[i] = -1;
       }
+      assert( pIdx==0 || pIdx->aiColumn[i]>=0 );
 #ifndef SQLITE_OMIT_AUTHORIZATION
       /* Request permission to read the parent key columns. If the 
       ** authorization callback returns SQLITE_IGNORE, behave as if any
       ** values read from the parent table are NULL. */
       if( db->xAuth ){
         int rcauth;
         char *zCol = pTo->aCol[pIdx ? pIdx->aiColumn[i] : pTo->iPKey].zName;
         rcauth = sqlite3AuthReadCol(pParse, pTo->zName, zCol, iDb);
-        isIgnore = (rcauth==SQLITE_IGNORE);
+        bIgnore = (rcauth==SQLITE_IGNORE);
       }
 #endif
     }
 
     /* Take a shared-cache advisory read-lock on the parent table. Allocate 
     ** a cursor to use to search the unique index on the parent key columns 
     ** in the parent table.  */
     sqlite3TableLock(pParse, iDb, pTo->tnum, 0, pTo->zName);
     pParse->nTab++;
 
     if( regOld!=0 ){
       /* A row is being removed from the child table. Search for the parent.
       ** If the parent does not exist, removing the child row resolves an 
       ** outstanding foreign key constraint violation. */
-      fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regOld, -1,isIgnore);
+      fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regOld, -1, bIgnore);
     }
-    if( regNew!=0 ){
+    if( regNew!=0 && !isSetNullAction(pParse, pFKey) ){
       /* A row is being added to the child table. If a parent row cannot
-      ** be found, adding the child row has violated the FK constraint. */ 
-      fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regNew, +1,isIgnore);
+      ** be found, adding the child row has violated the FK constraint. 
+      **
+      ** If this operation is being performed as part of a trigger program
+      ** that is actually a "SET NULL" action belonging to this very 
+      ** foreign key, then omit this scan altogether. As all child key
+      ** values are guaranteed to be NULL, it is not possible for adding
+      ** this row to cause an FK violation.  */
+      fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regNew, +1, bIgnore);
     }
 
     sqlite3DbFree(db, aiFree);
   }
 
   /* Loop through all the foreign key constraints that refer to this table.
   ** (the "child" constraints) */
   for(pFKey = sqlite3FkReferences(pTab); pFKey; pFKey=pFKey->pNextTo){
     Index *pIdx = 0;              /* Foreign key index for pFKey */
     SrcList *pSrc;
     int *aiCol = 0;
 
     if( aChange && fkParentIsModified(pTab, pFKey, aChange, bChngRowid)==0 ){
       continue;
     }
 
     if( !pFKey->isDeferred && !(db->flags & SQLITE_DeferFKs) 
      && !pParse->pToplevel && !pParse->isMultiWrite 
     ){
       assert( regOld==0 && regNew!=0 );
-      /* Inserting a single row into a parent table cannot cause an immediate
-      ** foreign key violation. So do nothing in this case.  */
+      /* Inserting a single row into a parent table cannot cause (or fix)
+      ** an immediate foreign key violation. So do nothing in this case.  */
       continue;
     }
 
     if( sqlite3FkLocateIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ){
       if( !isIgnoreErrors || db->mallocFailed ) return;
       continue;
     }
     assert( aiCol || pFKey->nCol==1 );
 
     /* Create a SrcList structure containing the child table.  We need the
     ** child table as a SrcList for sqlite3WhereBegin() */
     pSrc = sqlite3SrcListAppend(db, 0, 0, 0);
     if( pSrc ){
       struct SrcList_item *pItem = pSrc->a;
       pItem->pTab = pFKey->pFrom;
       pItem->zName = pFKey->pFrom->zName;
       pItem->pTab->nRef++;
       pItem->iCursor = pParse->nTab++;
   
       if( regNew!=0 ){
         fkScanChildren(pParse, pSrc, pTab, pIdx, pFKey, aiCol, regNew, -1);
       }
       if( regOld!=0 ){
-        /* If there is a RESTRICT action configured for the current operation
-        ** on the parent table of this FK, then throw an exception 
-        ** immediately if the FK constraint is violated, even if this is a
-        ** deferred trigger. That's what RESTRICT means. To defer checking
-        ** the constraint, the FK should specify NO ACTION (represented
-        ** using OE_None). NO ACTION is the default.  */
+        int eAction = pFKey->aAction[aChange!=0];
         fkScanChildren(pParse, pSrc, pTab, pIdx, pFKey, aiCol, regOld, 1);
+        /* If this is a deferred FK constraint, or a CASCADE or SET NULL
+        ** action applies, then any foreign key violations caused by
+        ** removing the parent key will be rectified by the action trigger.
+        ** So do not set the "may-abort" flag in this case.
+        **
+        ** Note 1: If the FK is declared "ON UPDATE CASCADE", then the
+        ** may-abort flag will eventually be set on this statement anyway
+        ** (when this function is called as part of processing the UPDATE
+        ** within the action trigger).
+        **
+        ** Note 2: At first glance it may seem like SQLite could simply omit
+        ** all OP_FkCounter related scans when either CASCADE or SET NULL
+        ** applies. The trouble starts if the CASCADE or SET NULL action 
+        ** trigger causes other triggers or action rules attached to the 
+        ** child table to fire. In these cases the fk constraint counters
+        ** might be set incorrectly if any OP_FkCounter related scans are 
+        ** omitted.  */
+        if( !pFKey->isDeferred && eAction!=OE_Cascade && eAction!=OE_SetNull ){
+          sqlite3MayAbort(pParse);
+        }
       }
       pItem->zName = 0;
       sqlite3SrcListDelete(db, pSrc);
     }
     sqlite3DbFree(db, aiCol);
   }
 }
 
 #define COLUMN_MASK(x) (((x)>31) ? 0xffffffff : ((u32)1<<(x)))
 
 /*
 ** This function is called before generating code to update or delete a 
 ** row contained in table pTab.
 */
 u32 sqlite3FkOldmask(
   Parse *pParse,                  /* Parse context */
   Table *pTab                     /* Table being modified */
 ){
   u32 mask = 0;
   if( pParse->db->flags&SQLITE_ForeignKeys ){
     FKey *p;
     int i;
     for(p=pTab->pFKey; p; p=p->pNextFrom){
       for(i=0; i<p->nCol; i++) mask |= COLUMN_MASK(p->aCol[i].iFrom);
     }
     for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
       Index *pIdx = 0;
       sqlite3FkLocateIndex(pParse, pTab, p, &pIdx, 0);
       if( pIdx ){
-        for(i=0; i<pIdx->nKeyCol; i++) mask |= COLUMN_MASK(pIdx->aiColumn[i]);
+        for(i=0; i<pIdx->nKeyCol; i++){
+          assert( pIdx->aiColumn[i]>=0 );
+          mask |= COLUMN_MASK(pIdx->aiColumn[i]);
+        }
       }
     }
   }
   return mask;
 }
 
 
 /*
 ** This function is called before generating code to update or delete a 
 ** row contained in table pTab. If the operation is a DELETE, then
@@ skipping 101 matching lines @@
     for(i=0; i<pFKey->nCol; i++){
       Token tOld = { "old", 3 };  /* Literal "old" token */
       Token tNew = { "new", 3 };  /* Literal "new" token */
       Token tFromCol;             /* Name of column in child table */
       Token tToCol;               /* Name of column in parent table */
       int iFromCol;               /* Idx of column in child table */
       Expr *pEq;                  /* tFromCol = OLD.tToCol */
 
       iFromCol = aiCol ? aiCol[i] : pFKey->aCol[0].iFrom;
       assert( iFromCol>=0 );
-      tToCol.z = pIdx ? pTab->aCol[pIdx->aiColumn[i]].zName : "oid";
+      assert( pIdx!=0 || (pTab->iPKey>=0 && pTab->iPKey<pTab->nCol) );
+      assert( pIdx==0 || pIdx->aiColumn[i]>=0 );
+      tToCol.z = pTab->aCol[pIdx ? pIdx->aiColumn[i] : pTab->iPKey].zName;
       tFromCol.z = pFKey->pFrom->aCol[iFromCol].zName;
 
       tToCol.n = sqlite3Strlen30(tToCol.z);
       tFromCol.n = sqlite3Strlen30(tFromCol.z);
 
       /* Create the expression "OLD.zToCol = zFromCol". It is important
       ** that the "OLD.zToCol" term is on the LHS of the = operator, so
       ** that the affinity and collation sequence associated with the
       ** parent table are used for the comparison. */
       pEq = sqlite3PExpr(pParse, TK_EQ,
           sqlite3PExpr(pParse, TK_DOT, 
-            sqlite3PExpr(pParse, TK_ID, 0, 0, &tOld),
-            sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol)
+            sqlite3ExprAlloc(db, TK_ID, &tOld, 0),
+            sqlite3ExprAlloc(db, TK_ID, &tToCol, 0)
           , 0),
-          sqlite3PExpr(pParse, TK_ID, 0, 0, &tFromCol)
+          sqlite3ExprAlloc(db, TK_ID, &tFromCol, 0)
       , 0);
       pWhere = sqlite3ExprAnd(db, pWhere, pEq);
 
       /* For ON UPDATE, construct the next term of the WHEN clause.
       ** The final WHEN clause will be like this:
       **
       **    WHEN NOT(old.col1 IS new.col1 AND ... AND old.colN IS new.colN)
       */
       if( pChanges ){
         pEq = sqlite3PExpr(pParse, TK_IS,
             sqlite3PExpr(pParse, TK_DOT, 
-              sqlite3PExpr(pParse, TK_ID, 0, 0, &tOld),
-              sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol),
+              sqlite3ExprAlloc(db, TK_ID, &tOld, 0),
+              sqlite3ExprAlloc(db, TK_ID, &tToCol, 0),
               0),
             sqlite3PExpr(pParse, TK_DOT, 
-              sqlite3PExpr(pParse, TK_ID, 0, 0, &tNew),
-              sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol),
+              sqlite3ExprAlloc(db, TK_ID, &tNew, 0),
+              sqlite3ExprAlloc(db, TK_ID, &tToCol, 0),
               0),
             0);
         pWhen = sqlite3ExprAnd(db, pWhen, pEq);
       }
   
       if( action!=OE_Restrict && (action!=OE_Cascade || pChanges) ){
         Expr *pNew;
         if( action==OE_Cascade ){
           pNew = sqlite3PExpr(pParse, TK_DOT, 
-            sqlite3PExpr(pParse, TK_ID, 0, 0, &tNew),
-            sqlite3PExpr(pParse, TK_ID, 0, 0, &tToCol)
+            sqlite3ExprAlloc(db, TK_ID, &tNew, 0),
+            sqlite3ExprAlloc(db, TK_ID, &tToCol, 0)
           , 0);
         }else if( action==OE_SetDflt ){
           Expr *pDflt = pFKey->pFrom->aCol[iFromCol].pDflt;
           if( pDflt ){
             pNew = sqlite3ExprDup(db, pDflt, 0);
           }else{
             pNew = sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
           }
         }else{
           pNew = sqlite3PExpr(pParse, TK_NULL, 0, 0, 0);
@@ skipping 26 matching lines @@
       pWhere = 0;
     }
 
     /* Disable lookaside memory allocation */
     enableLookaside = db->lookaside.bEnabled;
     db->lookaside.bEnabled = 0;
 
     pTrigger = (Trigger *)sqlite3DbMallocZero(db, 
         sizeof(Trigger) +         /* struct Trigger */
         sizeof(TriggerStep) +     /* Single step in trigger program */
-        nFrom + 1                 /* Space for pStep->target.z */
+        nFrom + 1                 /* Space for pStep->zTarget */
     );
     if( pTrigger ){
       pStep = pTrigger->step_list = (TriggerStep *)&pTrigger[1];
-      pStep->target.z = (char *)&pStep[1];
-      pStep->target.n = nFrom;
-      memcpy((char *)pStep->target.z, zFrom, nFrom);
+      pStep->zTarget = (char *)&pStep[1];
+      memcpy((char *)pStep->zTarget, zFrom, nFrom);
   
       pStep->pWhere = sqlite3ExprDup(db, pWhere, EXPRDUP_REDUCE);
       pStep->pExprList = sqlite3ExprListDup(db, pList, EXPRDUP_REDUCE);
       pStep->pSelect = sqlite3SelectDup(db, pSelect, EXPRDUP_REDUCE);
       if( pWhen ){
         pWhen = sqlite3PExpr(pParse, TK_NOT, pWhen, 0, 0);
         pTrigger->pWhen = sqlite3ExprDup(db, pWhen, EXPRDUP_REDUCE);
       }
     }
 
@@ skipping 98 matching lines @@
 #ifndef SQLITE_OMIT_TRIGGER
     fkTriggerDelete(db, pFKey->apTrigger[0]);
     fkTriggerDelete(db, pFKey->apTrigger[1]);
 #endif
 
     pNext = pFKey->pNextFrom;
     sqlite3DbFree(db, pFKey);
   }
 }
 #endif /* ifndef SQLITE_OMIT_FOREIGN_KEY */