| 1 | 3 | This wasn't done when we added the `on_delete` feature due to concerns about breaking backwards-compatibility with the previous always-cascade-deletes behavior. But if you set aside legacy considerations, it seems intuitively obvious (to me anyway) that SET_NULL is a superior default for a nullable FK than CASCADE. And even if others might have a different intuition, the consequences of your intuition being wrong are far from symmetrical: one way you get a model instance with a null FK hanging around that you didn't expect to still have, the other way you get data loss. |