-- -- Constraints for table `issues` -- ALTER TABLE `issues` ADD CONSTRAINT `issues_ibfk_1` FOREIGN KEY (`p_id`) REFERENCES `projects` (`id`) ON DELETE CASCADE ON UPDATE CASCADE, ADD CONSTRAINT `issues_ibfk_2` FOREIGN KEY (`u_id`) REFERENCES `users` (`id`) ON DELETE SET NULL ON UPDATE SET NULL, ADD CONSTRAINT `issues_ibfk_3` FOREIGN KEY (`pr_id`) REFERENCES `priorities` (`id`), ADD CONSTRAINT `issues_ibfk_4` FOREIGN KEY (`s_id`) REFERENCES `statuses` (`id`);