transaction; set db.DB_TXN_NOSYNC flag on an environment;

Remove lock limits; set db.DB_LOG_AUTOREMOVE flag; add checkpoints
on: open, batch transaction start and end; close.
* src/GrampsDb/_GrampsDbBase.py (change_database, no_database):
close existing db before changing to the new one.


svn: r5768

src/GrampsDb/_GrampsDbBase.py

@@ -1885,11 +1885,13 @@ class DbState(GrampsDBCallback):
         return self.active
 
     def change_database(self,db):
+        self.db.close()
         self.db = db
         self.open = True
         self.emit('database-changed',(self.db,))
 
     def no_database(self):
+        self.db.close()
         self.db = GrampsDbBase()
         self.open = False
         self.emit('no-database')