On Sunday 05 August 2007 21:43, snacktime wrote: > 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 Use a third table. The table would contain the order pk the address pk the line item pk -- John Fabiani ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
