I've been going back and forth on the best way to model this. A user can have one to many bill and ship addresses. An order can have one bill address and one to many ship addresses Let's assume I have a single address table, with an address_type column that is a foreign key to the address_types table. Now to create the relationships between addresses and users/orders. I could create a join table for holding the addresses that belong to orders. For example table order_addresses that has order_id and address_id columns that are foreign keys on addresses and orders. But what about just having two foreign keys in addresses? order_id and user_id? Or is there a rule against having a null foreign key? Also, is there a good database independent way to make the address immutable once it's created? I don't mind doing it at the application level actually, as I'm using a MVC framework that makes it easy to define that logic once in the model instead of spread out all over the codebase. Chris ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
