DELIMITER $$
CREATE OR REPLACE DEFINER=`root`@`localhost` FUNCTION `vn`.`hasAnyNegativeBase`()
	RETURNS tinyint(1)
	DETERMINISTIC
BEGIN

/*	Calcula si existe alguna base imponible negativa
*	Requiere la tabla temporal tmp.ticketToInvoice(id)
*
*	returns BOOLEAN
*/
	DECLARE hasAnyNegativeBase BOOLEAN;

	DROP TEMPORARY TABLE IF EXISTS tmp.ticket;
	CREATE TEMPORARY TABLE tmp.ticket
		(KEY (ticketFk))
		ENGINE = MEMORY
		SELECT id ticketFk
			FROM tmp.ticketToInvoice;

	CALL ticket_getTax(NULL);

	SELECT COUNT(*) INTO hasAnyNegativeBase
		FROM(
			SELECT SUM(taxableBase) as taxableBase
				FROM tmp.ticketTax
				GROUP BY pgcFk
				HAVING taxableBase < 0
			) t;

	DROP TEMPORARY TABLE tmp.ticketTax;
	DROP TEMPORARY TABLE tmp.ticket;

	RETURN hasAnyNegativeBase;

END$$
DELIMITER ;