From: Josh Berkus <josh@agliodbs.com>
Reply-To: josh@agliodbs.com
Organization: Aglio Database Solutions
To: Bruno Wolff III <bruno@wolff.to>
Subject: Re: multi column foreign key for implicitly unique columns
Date: Wed, 18 Aug 2004 12:36:14 -0700
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Bruno,

> If users is supposed to reference status you can do this by adding a
> relation column to users, using a constraint to force relation to always be
> 'users' and then having (status, relation) being a foreign key.

But that requires the addition of an extra, indexed Text column to the table.  
And the "status" reference table is not the only place I need this construct; 
I have other relationships to reference tables which are similar.   It would 
amount to adding probably a total of 25-40 columns to various tables in my 
database overall; maybe 100MB of completely redundant data.  :-(

I'll wait for ASSERTIONS, I think.

-- 
--Josh

Josh Berkus
Aglio Database Solutions
San Francisco