Question

I have 2 tables that have a 1-M relationship:

TABLE foo
 - foo_id (PK)
 - foobar_id
 - value

TABLE bar
 - bar_id (PK)
 - foo_id (FK to foo.foo_id)
 - foobar_id
 - value

I want to make sure foo.foobar_id and foo.value are unique, and thus want to make them a composite key. If I do that, then I can probably get rid of foo.foo_id. And if I do that, how do I relate foo and bar?

I also want bar.foo_id and bar.foobar_id to be unique, but will run into problems if I delete foo.foo_id.

Suggestions on how to model this?

Answer 1

Just create an unique index that covers both fields. In this case only unique pairs will be allowed.