Foreign key constraints: When to use ON UPDATE and ON DELETE

Question

I\'m designing my database schema using MySQL Workbench, which is pretty cool because you can do diagrams and it converts them :P

Anyways, I\'ve decided to use InnoD

Answer 1

Addition to @MarkR answer - one thing to note would be that many PHP frameworks with ORMs would not recognize or use advanced DB setup (foreign keys, cascading delete, unique constraints), and this may result in unexpected behaviour.

For example if you delete a record using ORM, and your DELETE CASCADE will delete records in related tables, ORM's attempt to delete these related records (often automatic) will result in error.