Re: Check Constraints and pg_dump - Mailing list pgsql-hackers

On Tue, 2 Mar 2004, Robert Treat wrote:

> Wouldn't a FK on both tables be the appropriate schema?  With the FK on
> contract being deffered?

Unfortunately, it appears that an FK must reference a unique column. So this:
   ALTER TABLE contract ADD CONSTRAINT contract_must_have_a_plan       FOREIGN KEY ( contract_id ) REFERENCES plan (
contract_id)       INITIALLY DEFERRED;
 

produces the error message:
   UNIQUE constraint matching given keys for referenced table "plan" not found

Since a plan may have more than one contract.

cjs
-- 
Curt Sampson  <cjs@cynic.net>   +81 90 7737 2974   http://www.NetBSD.org   Don't you know, in this new Dark Age, we're
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