protected static function _detectLimitClauseStyle($connection_name)
        {
            switch(self::get_db($connection_name)->getAttribute(PDO::ATTR_DRIVER_NAME)) {
                case 'sqlsrv':
                case 'dblib':
                case 'mssql':
                    return One::LIMIT_STYLE_TOP_N;
                default:
                    return One::LIMIT_STYLE_LIMIT;
            }
        }