Fix the VACUUM command so that it does not modify the changes counts

reported by sqlite3_changes() or sqlite3_total_changes().  Update documentation
on sqlite3_changes() and sqlite3_total_changes() to state that
"DELETE FROM table" records a change count of zero. (CVS 5151)

FossilOrigin-Name: f5d61d7d982b58accaf33df4362ce4a5eb79307e

2 files changed, 19 insertions, 4 deletions

diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 06f61b077..b584d8bf1 100644
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -30,7 +30,7 @@
 ** the version number) and changes its name to "sqlite3.h" as
 ** part of the build process.
 **
-** @(#) $Id: sqlite.h.in,v 1.315 2008/05/20 18:43:38 drh Exp $
+** @(#) $Id: sqlite.h.in,v 1.316 2008/05/21 13:44:14 drh Exp $
 */
 #ifndef _SQLITE3_H_
 #define _SQLITE3_H_
@@ -969,12 +969,17 @@ sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
 **
 ** INVARIANTS:
 **
-** {F12241} The [sqlite3_changes()] function returns the number of
+** {F12241} The [sqlite3_changes()] function shall return the number of
 **          row changes caused by the most recent INSERT, UPDATE,
 **          or DELETE statement on the same database connection and
-**          within the same trigger context, or zero if there have
+**          within the same or higher trigger context, or zero if there have
 **          not been any qualifying row changes.
 **
+** {F12243} Statements of the form "DELETE FROM tablename" with no
+**          WHERE clause shall cause subsequent calls to 
+**          [sqlite3_changes()] to return zero, regardless of the
+**          number of rows originally in the table.
+**
 ** LIMITATIONS:
 **
 ** {U12252} If a separate thread makes changes on the same database connection
@@ -1016,6 +1021,10 @@ int sqlite3_changes(sqlite3*);
 **          trigger context, since the database connection was
 **          created.
 **
+** {F12263} Statements of the form "DELETE FROM tablename" with no
+**          WHERE clause shall not change the value returned
+**          by [sqlite3_total_changes()]
+**
 ** LIMITATIONS:
 **
 ** {U12264} If a separate thread makes changes on the same database connection
diff --git a/src/vacuum.c b/src/vacuum.c
index 469c314d6..ea2f535ca 100644
--- a/src/vacuum.c
+++ b/src/vacuum.c
@@ -14,7 +14,7 @@
 ** Most of the code in this file may be omitted by defining the
 ** SQLITE_OMIT_VACUUM macro.
 **
-** $Id: vacuum.c,v 1.78 2008/04/30 16:38:23 drh Exp $
+** $Id: vacuum.c,v 1.79 2008/05/21 13:44:14 drh Exp $
 */
 #include "sqliteInt.h"
 #include "vdbeInt.h"
@@ -84,11 +84,15 @@ int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
   Btree *pTemp;           /* The temporary database we vacuum into */
   char *zSql = 0;         /* SQL statements */
   int saved_flags;        /* Saved value of the db->flags */
+  int saved_nChange;      /* Saved value of db->nChange */
+  int saved_nTotalChange; /* Saved value of db->nTotalChange */
   Db *pDb = 0;            /* Database to detach at end of vacuum */
   int nRes;
 
   /* Save the current value of the write-schema flag before setting it. */
   saved_flags = db->flags;
+  saved_nChange = db->nChange;
+  saved_nTotalChange = db->nTotalChange;
   db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;
 
   if( !db->autoCommit ){
@@ -253,6 +257,8 @@ int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
 end_of_vacuum:
   /* Restore the original value of db->flags */
   db->flags = saved_flags;
+  db->nChange = saved_nChange;
+  db->nTotalChange = saved_nTotalChange;
 
   /* Currently there is an SQL level transaction open on the vacuum
   ** database. No locks are held on any other files (since the main file