DELIMITER $$ CREATE OR REPLACE DEFINER=`vn`@`localhost` TRIGGER `vn`.`item_afterUpdate` AFTER UPDATE ON `item` FOR EACH ROW BEGIN IF !(NEW.image <=> OLD.image) THEN CALL hedera.image_unref('catalog', OLD.image); CALL hedera.image_ref('catalog', NEW.image); END IF; END$$ DELIMITER ;