DELIMITER $$
CREATE OR REPLACE DEFINER=`vn`@`localhost` FUNCTION `vn`.`invoiceOut_getPath`(vSelf INT)
	RETURNS varchar(255) CHARSET utf8mb3 COLLATE utf8mb3_general_ci
	DETERMINISTIC
BEGIN
	DECLARE vIssued DATE;
	DECLARE vSerial VARCHAR(15);

	SELECT issued, ref 
		INTO vIssued, vSerial
		FROM invoiceOut WHERE id = vSelf;

	RETURN CONCAT_WS('/'
		,'invoice'
		,YEAR(vIssued)
		,MONTH(vIssued)
		,DAY(vIssued)
		,CONCAT(YEAR(vIssued), vSerial, '.pdf')
	);
END$$
DELIMITER ;