Re: Surrogate Key vs Production Key

Cris Carampa <cris119_at_operamail.com> wrote in message news:<ckirpr$h64$1_at_lacerta.tiscalinet.it>...
> Mark C. Stock wrote:
>
> > but when establishing the data model, introducing a surrogate key column to
> > replace a natural key column structure seriously weakens the data model and
> > often hides (or impedes discovery of) very important facts about the
> > business
>
> Good point. But what happens if the natural key is made of more than one
> column? Do you still use it (and have all the child tables inherit it -
> this surely enforces the business rules but wastes hd space) or do you
> define a surrogate key instead?

Didn't the example in that post already answer that question? :-

department_vehicle

- dept_id -- pk, fk to department
- veh_id -- pk, fk to vehicle
- ...