As I was looking at model inheritance with admin recently, I came across this issue: http://code.djangoproject.com/ticket/6755
I'm thinking now that the underlying issue that I'm seeing, and what the patch in 6755 is fixing, doesn't actually have anything to do with newforms at all. I think it has to do with consistancy of primary keys in derived models. I don't know if this is a bug, or my own misuse, but I have a feeling something isn't right here. Using the Place,Restaurant example (class Place(models.model), and class Restaurant(Place)), let's consider what exactly a primary key of a restaurant is. At the database, both the restaurant and place tables have a primary key. By default, the names are place.id and restaurant.place_id_ptr (I think -- but they aren't the same). And so, in memory, a Restaurant object r has a property "pk" which is mapped to r.place_id_ptr. Similarly, a place object's property "pk" is mapped to p.id. So what exactly does r.pk = 1 do? It sets r.place_id_ptr. Is this wrong? Shouldn't it also set r.id? To me, this is one object, with the same primary key across 2 tables. If it were 2 keys, then one would be a foreign key. But it's not, so it's conceptually one key. Alternatively, this is my own bug if it should be the responsibility of the user to manage both keys independently. In any case, this fix is what the patch for 6755 kind of does. In the save_base model method, it sets the parent's primary key (r.id) from the child's (r.place_id_ptr) before saving the parent. I don't think in any case this is the right design. If the parent's primary set is to be set from the child's it should be set *on assignment* to r.pk, or r.place_ptr_id, or both, and not *on saving* to the database. It is more intuitive to me that an assignment to r.pk should set the primary key in the Restaurant class, as well as the primary key in all parent classes, as the "pk" property is not a database column -- it refers to a value of the object that is stored in 2 locations. What does the list think? Elizabeth --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
