Am Mittwoch, 28. März 2007 00:17 schrieb Phillip Smith:
> Perhaps this...? It would work, but depending how many rows are in the
> table, it could become incredibly slow.
>
> ALTER TABLE table1 ADD CHECK (extension NOT IN (SELECT extension FROM
> table2));
Subqueries are not allowed in check constraints.
--
Peter Eisentraut
http://developer.postgresql.org/~petere/