public static function getConnection($filter = ''){
		switch ($filter) {
			case 'host':
				return self::$_host;
				break;

			case 'port':
				return self::$_port;
				break;

			case 'dbname':
				return self::$_dbname;
				break;

			case 'user':
				return self::$_user;
				break;
			
			default:
				return self::$_pdo;
				break;
		}
	}