On Tue, Jan 06, 2004 at 07:10:28 +0000,
Randall Smith <randall(at)tnr(dot)cc> wrote:
> Is it possible to create a unique constraint on multiple fields in
> related tables?
Not with the normal UNIQUE constraint. That will do multiple columns in
one table, but won't span tables.
You can probably do what you want using triggers.