def get_last_tid(self):
        try:
            spec = {'tid': {'$gt': 0}}
            sort = [('tid', -1)]
            row = self.db.docs.find_one(spec, sort=sort)
        except Exception as e:
            raise DatabaseException(e)
        if row:
            return row['tid']
        return 0
def _Delete(self):
    """Delete the log group."""
    delete_cmd = util.AWS_PREFIX + [
        '--region', self.region,
        'logs', 'delete-log-group',
        '--log-group-name', self.name
    ]
    vm_util.IssueCommand(delete_cmd, raise_on_failure=False)