DELIMITER $$ CREATE OR REPLACE DEFINER=`vn`@`localhost` TRIGGER `vn`.`roadmap_beforeUpdate` BEFORE UPDATE ON `roadmap` FOR EACH ROW BEGIN IF NEW.driver1Fk IS NOT NULL THEN SET NEW.driverName = (SELECT firstName FROM worker WHERE id = NEW.driver1Fk); ELSE SET NEW.driverName = NULL; END IF; END$$ DELIMITER ;