DELIMITER $$
CREATE OR REPLACE DEFINER=`root`@`localhost` PROCEDURE `vn`.`item_multipleBuy`(
    vDate DATETIME,
    vWarehouseFk INT
)
BEGIN
/**
 * Updates the tmp.itemInventory table, adding the buy id.
 *
 * @param tmp.itemInventory(buy_id)
 * @param vDate -> Date of the purchase operation.
 * @param vWarehouseFk -> Identifier of the warehouse (warehouseId).
 */
	ALTER TABLE tmp.itemInventory ADD IF NOT EXISTS buy_id INT;

	CALL buyUltimate(vWarehouseFk, vDate);

	CREATE OR REPLACE TEMPORARY TABLE tmp
		(KEY (itemFk))
		ENGINE = MEMORY
		SELECT * 
            FROM (
                SELECT itemFk, buyFk
                    FROM tmp.buyUltimate
                    ORDER BY (vWarehouseFk = warehouseFk) DESC, landing DESC
                    LIMIT 10000000000000000000
            ) t
		    GROUP BY itemFk;

	UPDATE tmp.itemInventory ai
		    JOIN tmp t ON ai.id = t.itemFk
		SET ai.buy_id = t.buyFk;

	DROP TEMPORARY TABLE tmp, tmp.buyUltimate;
END$$
DELIMITER ;