/**
* 返回一个数据库对象,该服务器为写数据准备
*
* @return MooMySQL
*/
public function getWriteConnection()
{
if (self::$write_conn != null) {
return self::$write_conn;
}
self::$write_conn = $this->createConnection($this->write_host);
return self::$write_conn;
}