From: Richard Huxton <dev@archonet.com>
To: katarn <katarn@racsa.co.cr>, pgsql-sql@postgresql.org
Subject: Re: Unique key field or serverl fks ?
Date: Mon, 12 Jan 2004 09:52:53 +0000
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On Monday 12 January 2004 05:51, katarn wrote:
> Hi,
>
> I would like to know opinions about which approach is better:
>
> Having a table with a field that works as a unique key, or having
> several fks that work as a combined key ( all the fks fields )?

Depends on the particular situation, you'll need to give details of the tables 
and their place in your system.

There are two reasons I've seen given for using an artificial (substitute) 
primary key:
1. It's "lighter" than several other fields (especially where they are text)
2. The natural primary key has meaning to the users, and the users will tend 
to get it wrong.

The second is probably the more persuasive - the first can definitely have 
costs as well as benefits.

-- 
  Richard Huxton
  Archonet Ltd