On Wednesday, March 13, 2002 11:53 AM Behalf Of Andre Schubert wrote:
> Hi to all,
>
> i have a simple problem and wont request assistance fro m this list.
> i have to tables
>
> foo:
> id int8 UNIQUE
>
> bar:
> id int8 UNIQUE
> foo_id int8
>
> Now i wont foo_id to be a id which exists in the foo, this could be done
> with foo_id REFERENCES foo (id).
> But what should i do if i want foo_id to be a id existing in foo or to
> be zero(0).
> I have created a view as "select id from foo UNION select 0" and tried
> to REFERENCE against this view, but that
> doesnt work.
> Can this problem be solved by a somebody ????
>
> Thanks
Why do you want to use zeros? A foreign key could be NULL.
Regards, Tibor
ltibor@mail.tiszanet.hu
