Modifications to pass a flag to internal routine sqlite3BtreeCursor() when a cursor that is used solely for deleting b-tree entries, or for obtaining the components of keys to delete from other b-trees, is opened.

FossilOrigin-Name: cdc92919e600007cae5eb61223684f48a65babc0

11 files changed, 37 insertions, 17 deletions

diff --git a/src/btree.c b/src/btree.c
index b26a95c80..4ebaf4c27 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -4055,13 +4055,16 @@ static int btreeCursor(
   BtCursor *pX;                          /* Looping over other all cursors */
 
   assert( sqlite3BtreeHoldsMutex(p) );
-  assert( wrFlag==0 || wrFlag==1 );
+  assert( wrFlag==0 
+       || wrFlag==BTREE_WRCSR 
+       || wrFlag==(BTREE_WRCSR|BTREE_FORDELETE) 
+  );
 
   /* The following assert statements verify that if this is a sharable 
   ** b-tree database, the connection is holding the required table locks, 
   ** and that no other connection has any open cursor that conflicts with 
   ** this lock.  */
-  assert( hasSharedCacheTableLock(p, iTable, pKeyInfo!=0, wrFlag+1) );
+  assert( hasSharedCacheTableLock(p, iTable, pKeyInfo!=0, (wrFlag?2:1)) );
   assert( wrFlag==0 || !hasReadConflicts(p, iTable) );
 
   /* Assert that the caller has opened the required transaction. */
@@ -4086,8 +4089,7 @@ static int btreeCursor(
   pCur->pKeyInfo = pKeyInfo;
   pCur->pBtree = p;
   pCur->pBt = pBt;
-  assert( wrFlag==0 || wrFlag==BTCF_WriteFlag );
-  pCur->curFlags = wrFlag;
+  pCur->curFlags = wrFlag ? BTCF_WriteFlag : 0;
   pCur->curPagerFlags = wrFlag ? 0 : PAGER_GET_READONLY;
   /* If there are two or more cursors on the same btree, then all such
   ** cursors *must* have the BTCF_Multiple flag set. */
diff --git a/src/btree.h b/src/btree.h
index f7e92a260..66420f841 100644
--- a/src/btree.h
+++ b/src/btree.h
@@ -165,6 +165,12 @@ int sqlite3BtreeNewDb(Btree *p);
 #define BTREE_BULKLOAD 0x00000001  /* Used to full index in sorted order */
 #define BTREE_SEEK_EQ  0x00000002  /* EQ seeks only - no range seeks */
 
+/* 
+** Flags passed as the third argument to sqlite3BtreeCursor().
+*/
+#define BTREE_WRCSR     0x00000004  /* read-write cursor */
+#define BTREE_FORDELETE 0x00000008  /* Cursor is for seek/delete only */
+
 int sqlite3BtreeCursor(
   Btree*,                              /* BTree containing table to open */
   int iTable,                          /* Index of root page */
diff --git a/src/delete.c b/src/delete.c
index faef3a814..cd683e37d 100644
--- a/src/delete.c
+++ b/src/delete.c
@@ -478,12 +478,13 @@ void sqlite3DeleteFrom(
     */
     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);
diff --git a/src/insert.c b/src/insert.c
index 9274b0771..3d213a8d3 100644
--- a/src/insert.c
+++ b/src/insert.c
@@ -762,7 +762,7 @@ void sqlite3Insert(
   /* If this is not a view, open the table and and all indices */
   if( !isView ){
     int nIdx;
-    nIdx = sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, -1, 0,
+    nIdx = sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, 0, -1, 0,
                                       &iDataCur, &iIdxCur);
     aRegIdx = sqlite3DbMallocRaw(db, sizeof(int)*(nIdx+1));
     if( aRegIdx==0 ){
@@ -1650,6 +1650,7 @@ int sqlite3OpenTableAndIndices(
   Parse *pParse,   /* Parsing context */
   Table *pTab,     /* Table to be opened */
   int op,          /* OP_OpenRead or OP_OpenWrite */
+  u8 p5,           /* P5 value for OP_Open* instructions */
   int iBase,       /* Use this for the table cursor, if there is one */
   u8 *aToOpen,     /* If not NULL: boolean for each table and index */
   int *piDataCur,  /* Write the database source cursor number here */
@@ -1662,6 +1663,7 @@ int sqlite3OpenTableAndIndices(
   Vdbe *v;
 
   assert( op==OP_OpenRead || op==OP_OpenWrite );
+  assert( op==OP_OpenWrite || p5==0 );
   if( IsVirtual(pTab) ){
     /* This routine is a no-op for virtual tables. Leave the output
     ** variables *piDataCur and *piIdxCur uninitialized so that valgrind
@@ -1689,6 +1691,7 @@ int sqlite3OpenTableAndIndices(
     if( aToOpen==0 || aToOpen[i+1] ){
       sqlite3VdbeAddOp3(v, op, iIdxCur, pIdx->tnum, iDb);
       sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
+      sqlite3VdbeChangeP5(v, p5);
       VdbeComment((v, "%s", pIdx->zName));
     }
   }
diff --git a/src/pragma.c b/src/pragma.c
index 64614a7eb..14c481174 100644
--- a/src/pragma.c
+++ b/src/pragma.c
@@ -1465,7 +1465,7 @@ void sqlite3Pragma(
         sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
         sqlite3VdbeJumpHere(v, addr);
         sqlite3ExprCacheClear(pParse);
-        sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenRead,
+        sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenRead, 0,
                                    1, 0, &iDataCur, &iIdxCur);
         sqlite3VdbeAddOp2(v, OP_Integer, 0, 7);
         for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 9c28a9a8c..7d0130596 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -2794,7 +2794,8 @@ struct AuthContext {
 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
 #define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
 #define OPFLAG_SEEKEQ        0x02    /* OP_Open** cursor uses EQ seek only */
-#define OPFLAG_P2ISREG       0x04    /* P2 to OP_Open** is a register number */
+#define OPFLAG_FORDELETE     0x08    /* OP_Open is opening for-delete csr */
+#define OPFLAG_P2ISREG       0x10    /* P2 to OP_Open** is a register number */
 #define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
 
 /*
@@ -3460,7 +3461,7 @@ void sqlite3ResolvePartIdxLabel(Parse*,int);
 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
                                      u8,u8,int,int*);
 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
-int sqlite3OpenTableAndIndices(Parse*, Table*, int, int, u8*, int*, int*);
+int sqlite3OpenTableAndIndices(Parse*, Table*, int, u8, int, u8*, int*, int*);
 void sqlite3BeginWriteOperation(Parse*, int, int);
 void sqlite3MultiWrite(Parse*);
 void sqlite3MayAbort(Parse*);
diff --git a/src/test3.c b/src/test3.c
index 07d12d28c..7cb29bedc 100644
--- a/src/test3.c
+++ b/src/test3.c
@@ -214,6 +214,7 @@ static int btree_cursor(
   pBt = sqlite3TestTextToPtr(argv[1]);
   if( Tcl_GetInt(interp, argv[2], &iTable) ) return TCL_ERROR;
   if( Tcl_GetBoolean(interp, argv[3], &wrFlag) ) return TCL_ERROR;
+  if( wrFlag ) wrFlag = BTREE_WRCSR;
   pCur = (BtCursor *)ckalloc(sqlite3BtreeCursorSize());
   memset(pCur, 0, sqlite3BtreeCursorSize());
   sqlite3BtreeEnter(pBt);
diff --git a/src/update.c b/src/update.c
index 5cb557490..1335c269e 100644
--- a/src/update.c
+++ b/src/update.c
@@ -429,7 +429,7 @@ void sqlite3Update(
       if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iBaseCur] = 0;
       if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iBaseCur] = 0;
     }
-    sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, iBaseCur, aToOpen,
+    sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, 0, iBaseCur, aToOpen,
                                0, 0);
   }
 
diff --git a/src/vdbe.c b/src/vdbe.c
index b93ab160f..9b391c14d 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -3324,7 +3324,6 @@ case OP_ReopenIdx: {
 case OP_OpenRead:
 case OP_OpenWrite:
 
-  assert( (pOp->p5&(OPFLAG_P2ISREG|OPFLAG_BULKCSR|OPFLAG_SEEKEQ))==pOp->p5 );
   assert( pOp->opcode==OP_OpenWrite || pOp->p5==0 || pOp->p5==OPFLAG_SEEKEQ );
   assert( p->bIsReader );
   assert( pOp->opcode==OP_OpenRead || pOp->opcode==OP_ReopenIdx
@@ -3345,7 +3344,8 @@ case OP_OpenWrite:
   pX = pDb->pBt;
   assert( pX!=0 );
   if( pOp->opcode==OP_OpenWrite ){
-    wrFlag = 1;
+    assert( OPFLAG_FORDELETE==BTREE_FORDELETE );
+    wrFlag = BTREE_WRCSR | (pOp->p5 & OPFLAG_FORDELETE);
     assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
     if( pDb->pSchema->file_format < p->minWriteFileFormat ){
       p->minWriteFileFormat = pDb->pSchema->file_format;
@@ -3465,11 +3465,11 @@ case OP_OpenEphemeral: {
         assert( pKeyInfo->db==db );
         assert( pKeyInfo->enc==ENC(db) );
         pCx->pKeyInfo = pKeyInfo;
-        rc = sqlite3BtreeCursor(pCx->pBt, pgno, 1, pKeyInfo, pCx->pCursor);
+        rc = sqlite3BtreeCursor(pCx->pBt, pgno, BTREE_WRCSR, pKeyInfo, pCx->pCursor);
       }
       pCx->isTable = 0;
     }else{
-      rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, 1, 0, pCx->pCursor);
+      rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, BTREE_WRCSR, 0, pCx->pCursor);
       pCx->isTable = 1;
     }
   }
diff --git a/src/where.c b/src/where.c
index af8e2f35f..3f83511b0 100644
--- a/src/where.c
+++ b/src/where.c
@@ -3991,6 +3991,7 @@ WhereInfo *sqlite3WhereBegin(
   int ii;                    /* Loop counter */
   sqlite3 *db;               /* Database connection */
   int rc;                    /* Return code */
+  u8 bFordelete = 0;
 
   assert( (wctrlFlags & WHERE_ONEPASS_MULTIROW)==0 || (
         (wctrlFlags & WHERE_ONEPASS_DESIRED)!=0 
@@ -4246,8 +4247,11 @@ WhereInfo *sqlite3WhereBegin(
        && 0==(wsFlags & WHERE_VIRTUALTABLE)
     )){
       pWInfo->eOnePass = bOnerow ? ONEPASS_SINGLE : ONEPASS_MULTI;
-      if( HasRowid(pTabList->a[0].pTab) ){
-        pWInfo->a[0].pWLoop->wsFlags &= ~WHERE_IDX_ONLY;
+      if( HasRowid(pTabList->a[0].pTab) && (wsFlags & WHERE_IDX_ONLY) ){
+        if( wctrlFlags & WHERE_ONEPASS_MULTIROW ){
+          bFordelete = OPFLAG_FORDELETE;
+        }
+        pWInfo->a[0].pWLoop->wsFlags = (wsFlags & ~WHERE_IDX_ONLY);
       }
     }
   }
@@ -4284,6 +4288,7 @@ WhereInfo *sqlite3WhereBegin(
         pWInfo->aiCurOnePass[0] = pTabItem->iCursor;
       };
       sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, op);
+      sqlite3VdbeChangeP5(v, bFordelete);
       assert( pTabItem->iCursor==pLevel->iTabCur );
       testcase( pWInfo->eOnePass==ONEPASS_OFF && pTab->nCol==BMS-1 );
       testcase( pWInfo->eOnePass==ONEPASS_OFF && pTab->nCol==BMS );
diff --git a/src/whereInt.h b/src/whereInt.h
index cae09acc8..f4bc4077e 100644
--- a/src/whereInt.h
+++ b/src/whereInt.h
@@ -530,3 +530,4 @@ void sqlite3WhereTabFuncArgs(Parse*, struct SrcList_item*, WhereClause*);
 #define WHERE_SKIPSCAN     0x00008000  /* Uses the skip-scan algorithm */
 #define WHERE_UNQ_WANTED   0x00010000  /* WHERE_ONEROW would have been helpful*/
 #define WHERE_PARTIALIDX   0x00020000  /* The automatic index is partial */
+#define WHERE_FORDELETE    0x00040000  /* Table cursor is "for-delete" */