Mario Splivalo <mario.spliv...@megafon.hr> writes: > I have two tables, tableA and tableB: > CREATE TABLE tableA (idA integer primary key, email character varying > unique); > CREATE TABLE tableB (idB integer primary key, email character varying > unique);
> Now, I want to create check constraint in both tables that would > disallow records to either table where email is 'mentioned' in other table. Have you considered refactoring so there's only one table? Cross-table constraints are a really bad idea unless you can express them as foreign keys. There's a lot of "secret sauce" in the FK mechanism that isn't available to user-written constraints. regards, tom lane -- Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-sql