ALTER TABLE `vn`.`route` 
ADD COLUMN `zoneFk` INT NULL AFTER `description`,
ADD INDEX `fk_route_1_idx` (`zoneFk` ASC);
;
ALTER TABLE `vn`.`route` 
ADD CONSTRAINT `fk_route_1`
  FOREIGN KEY (`zoneFk`)
  REFERENCES `vn`.`zone` (`id`)
  ON DELETE RESTRICT
  ON UPDATE CASCADE;