def close(self):
		'''关闭与数据库的连接'''
		if VERBOSE:
			print 'Database connection CLOSE.'
		self.conn.close()
def closeCliConnectionTo(self):
        if self._connection == None:
            return
        self._exit_modes_beyond(-1)
        self.modeList = []
        self._debugLog("Exited all modes.")
        self.forceCloseCliConnectionTo()