def _poll (self):
        """Fetch new messages from database and append to mailbox.
        """
        for row in list(self.db.execute(RECV_MESSAGES, (self.seen,))):
            self.seen, source, dest, blob = row
            if source != self.name and fnmatch.fnmatch(self.name, dest):
                tag, data = cPickle.loads(str(blob))
                self.mbox.append((self.seen, source, tag, data))
Fetch new messages from database and append to mailbox.
        
recipes/Python/577001_sqlite_message_bus/recipe-577001.py