I'm working on a little support (ticket) system. My tables are tickets and ticket_replies.
Design of tickets table is
id|user_id|title|...
Design of ticket_replies looks like:
id|ticket_id|...
The foreign key I added looks like this:
ALTER TABLE `ticket_replies` ADDFOREIGN KEY (`ticket_id`)
REFERENCES `sampleauth`.`tickets`(`id`) ON DELETE CASCADE ON UPDATE CASCADE;
Now when I delete a "ticket" in the "ticket" table it gets deleted in "ticket_replies" too. The other way this doesn't work, all in all I would like this to work the other way too, so my database has all the time consistency. How to do so?
Add this trigger will delete its primary key when you try to delete foreign key
CREATE TRIGGER `ticket_replies_BEFORE_DELETE` BEFORE DELETE ON `ticket_replies` FOR EACH ROW
BEGIN
DELETE FROM tickets WHERE id = OLD.ticket_id;
END
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