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From: gvim <gvimrc@gmail.com>
To: pgsql-sql@postgresql.org
Subject: 3 foreign keys in 1 table for 3 1-to-many relations?
Date: Thu, 18 Jun 2015 01:51:43 +0100
Message-ID: <5582161F.7070809@gmail.com> (raw)
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I have 3 tables A, B & C each of which has a 1-to-many relation with a 
Comments table but I can't fathom how to set up the foreign key(s) in 
Comments without resorting to distinct A_id, B_id & C_id columns in 
Comments and enforcing 2 of the 3 columns be NULL for a given row. Seems 
ugly.

gvim


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