Make sqlite3_count_changes() and total_changes() work with "DELETE FROM <table-name>". (CVS 5844)

FossilOrigin-Name: e68e4282adb9003aa297d033aeb5d9cadee215cd

5 files changed, 40 insertions, 27 deletions

diff --git a/src/btree.c b/src/btree.c
index 538a706d6..d94d9857a 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -9,7 +9,7 @@
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** $Id: btree.c,v 1.525 2008/10/08 17:58:49 danielk1977 Exp $
+** $Id: btree.c,v 1.526 2008/10/27 13:59:34 danielk1977 Exp $
 **
 ** This file implements a external (disk-based) database using BTrees.
 ** See the header comment on "btreeInt.h" for additional information.
@@ -6187,7 +6187,8 @@ static int clearDatabasePage(
   BtShared *pBt,           /* The BTree that contains the table */
   Pgno pgno,            /* Page number to clear */
   MemPage *pParent,     /* Parent page.  NULL for the root */
-  int freePageFlag      /* Deallocate page if true */
+  int freePageFlag,     /* Deallocate page if true */
+  int *pnChange
 ){
   MemPage *pPage = 0;
   int rc;
@@ -6204,15 +6205,18 @@ static int clearDatabasePage(
   for(i=0; i<pPage->nCell; i++){
     pCell = findCell(pPage, i);
     if( !pPage->leaf ){
-      rc = clearDatabasePage(pBt, get4byte(pCell), pPage, 1);
+      rc = clearDatabasePage(pBt, get4byte(pCell), pPage, 1, pnChange);
       if( rc ) goto cleardatabasepage_out;
     }
     rc = clearCell(pPage, pCell);
     if( rc ) goto cleardatabasepage_out;
   }
   if( !pPage->leaf ){
-    rc = clearDatabasePage(pBt, get4byte(&pPage->aData[8]), pPage, 1);
+    rc = clearDatabasePage(pBt, get4byte(&pPage->aData[8]), pPage, 1, pnChange);
     if( rc ) goto cleardatabasepage_out;
+  }else if( pnChange ){
+    assert( pPage->intKey );
+    *pnChange += pPage->nCell;
   }
   if( freePageFlag ){
     rc = freePage(pPage);
@@ -6233,8 +6237,12 @@ cleardatabasepage_out:
 ** This routine will fail with SQLITE_LOCKED if there are any open
 ** read cursors on the table.  Open write cursors are moved to the
 ** root of the table.
+**
+** If pnChange is not NULL, then table iTable must be an intkey table. The
+** integer value pointed to by pnChange is incremented by the number of
+** entries in the table.
 */
-int sqlite3BtreeClearTable(Btree *p, int iTable){
+int sqlite3BtreeClearTable(Btree *p, int iTable, int *pnChange){
   int rc;
   BtShared *pBt = p->pBt;
   sqlite3BtreeEnter(p);
@@ -6246,7 +6254,7 @@ int sqlite3BtreeClearTable(Btree *p, int iTable){
   }else if( SQLITE_OK!=(rc = saveAllCursors(pBt, iTable, 0)) ){
     /* nothing to do */
   }else{
-    rc = clearDatabasePage(pBt, (Pgno)iTable, 0, 0);
+    rc = clearDatabasePage(pBt, (Pgno)iTable, 0, 0, pnChange);
   }
   sqlite3BtreeLeave(p);
   return rc;
@@ -6294,7 +6302,7 @@ static int btreeDropTable(Btree *p, int iTable, int *piMoved){
 
   rc = sqlite3BtreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
   if( rc ) return rc;
-  rc = sqlite3BtreeClearTable(p, iTable);
+  rc = sqlite3BtreeClearTable(p, iTable, 0);
   if( rc ){
     releasePage(pPage);
     return rc;
diff --git a/src/btree.h b/src/btree.h
index 3f8c4ea4b..ba1673086 100644
--- a/src/btree.h
+++ b/src/btree.h
@@ -13,7 +13,7 @@
 ** subsystem.  See comments in the source code for a detailed description
 ** of what each interface routine does.
 **
-** @(#) $Id: btree.h,v 1.104 2008/10/08 17:58:49 danielk1977 Exp $
+** @(#) $Id: btree.h,v 1.105 2008/10/27 13:59:34 danielk1977 Exp $
 */
 #ifndef _BTREE_H_
 #define _BTREE_H_
@@ -117,7 +117,7 @@ int sqlite3BtreeIncrVacuum(Btree *);
 #define BTREE_LEAFDATA   4    /* Data stored in leaves only.  Implies INTKEY */
 
 int sqlite3BtreeDropTable(Btree*, int, int*);
-int sqlite3BtreeClearTable(Btree*, int);
+int sqlite3BtreeClearTable(Btree*, int, int*);
 int sqlite3BtreeGetMeta(Btree*, int idx, u32 *pValue);
 int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
 void sqlite3BtreeTripAllCursors(Btree*, int);
diff --git a/src/delete.c b/src/delete.c
index ef036cba9..382f1a67f 100644
--- a/src/delete.c
+++ b/src/delete.c
@@ -12,7 +12,7 @@
 ** This file contains C code routines that are called by the parser
 ** in order to generate code for DELETE FROM statements.
 **
-** $Id: delete.c,v 1.183 2008/10/27 08:24:38 danielk1977 Exp $
+** $Id: delete.c,v 1.184 2008/10/27 13:59:34 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 
@@ -233,7 +233,7 @@ void sqlite3DeleteFrom(
   int oldIdx = -1;       /* Cursor for the OLD table of AFTER triggers */
   NameContext sNC;       /* Name context to resolve expressions in */
   int iDb;               /* Database number */
-  int memCnt = 0;        /* Memory cell used for change counting */
+  int memCnt = -1;       /* Memory cell used for change counting */
 
 #ifndef SQLITE_OMIT_TRIGGER
   int isView;                  /* True if attempting to delete from a view */
@@ -372,17 +372,7 @@ void sqlite3DeleteFrom(
   */
   if( pWhere==0 && !triggers_exist && !IsVirtual(pTab) ){
     assert( !isView );
-    if( db->flags & SQLITE_CountRows ){
-      /* If counting rows deleted, just count the total number of
-      ** entries in the table. */
-      int addr2;
-      sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
-      sqlite3VdbeAddOp2(v, OP_Rewind, iCur, sqlite3VdbeCurrentAddr(v)+2);
-      addr2 = sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
-      sqlite3VdbeAddOp2(v, OP_Next, iCur, addr2);
-      sqlite3VdbeAddOp1(v, OP_Close, iCur);
-    }
-    sqlite3VdbeAddOp2(v, OP_Clear, pTab->tnum, iDb);
+    sqlite3VdbeAddOp3(v, OP_Clear, pTab->tnum, iDb, memCnt);
     if( !pParse->nested ){
       sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
     }
diff --git a/src/test3.c b/src/test3.c
index 4b75690ff..0d915f3cb 100644
--- a/src/test3.c
+++ b/src/test3.c
@@ -13,7 +13,7 @@
 ** is not included in the SQLite library.  It is used for automated
 ** testing of the SQLite library.
 **
-** $Id: test3.c,v 1.101 2008/08/13 19:11:48 drh Exp $
+** $Id: test3.c,v 1.102 2008/10/27 13:59:34 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 #include "btreeInt.h"
@@ -389,7 +389,7 @@ static int btree_clear_table(
   pBt = sqlite3TestTextToPtr(argv[1]);
   if( Tcl_GetInt(interp, argv[2], &iTable) ) return TCL_ERROR;
   sqlite3BtreeEnter(pBt);
-  rc = sqlite3BtreeClearTable(pBt, iTable);
+  rc = sqlite3BtreeClearTable(pBt, iTable, 0);
   sqlite3BtreeLeave(pBt);
   if( rc!=SQLITE_OK ){
     Tcl_AppendResult(interp, errorName(rc), 0);
diff --git a/src/vdbe.c b/src/vdbe.c
index 6ee22c1b6..a4a62b8bd 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -43,7 +43,7 @@
 ** in this file for details.  If in doubt, do not deviate from existing
 ** commenting and indentation practices when changing or adding code.
 **
-** $Id: vdbe.c,v 1.782 2008/10/08 17:58:49 danielk1977 Exp $
+** $Id: vdbe.c,v 1.783 2008/10/27 13:59:34 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -4042,7 +4042,7 @@ case OP_Destroy: {     /* out2-prerelease */
   break;
 }
 
-/* Opcode: Clear P1 P2 *
+/* Opcode: Clear P1 P2 P3
 **
 ** Delete all contents of the database table or index whose root page
 ** in the database file is given by P1.  But, unlike Destroy, do not
@@ -4052,11 +4052,26 @@ case OP_Destroy: {     /* out2-prerelease */
 ** P2==1 then the table to be clear is in the auxiliary database file
 ** that is used to store tables create using CREATE TEMPORARY TABLE.
 **
+** If the P3 value is non-zero, then the table refered to must be an
+** intkey table (an SQL table, not an index). In this case the row change 
+** count is incremented by the number of rows in the table being cleared. 
+** If P3 is greater than zero, then the value stored in register P3 is
+** also incremented by the number of rows in the table being cleared.
+**
 ** See also: Destroy
 */
 case OP_Clear: {
+  int nChange = 0;
   assert( (p->btreeMask & (1<<pOp->p2))!=0 );
-  rc = sqlite3BtreeClearTable(db->aDb[pOp->p2].pBt, pOp->p1);
+  rc = sqlite3BtreeClearTable(
+      db->aDb[pOp->p2].pBt, pOp->p1, (pOp->p3 ? &nChange : 0)
+  );
+  if( pOp->p3 ){
+    p->nChange += nChange;
+    if( pOp->p3>0 ){
+      p->aMem[pOp->p3].u.i += nChange;
+    }
+  }
   break;
 }