From: | "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com> |
---|---|
To: | Sam Mason <sam(at)samason(dot)me(dot)uk> |
Cc: | pgsql-general(at)postgresql(dot)org |
Subject: | Re: Primary Key |
Date: | 2007-11-16 19:01:15 |
Message-ID: | 20071116110115.040ec1f9@commandprompt.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
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On Fri, 16 Nov 2007 18:54:22 +0000
Sam Mason <sam(at)samason(dot)me(dot)uk> wrote:
> On Fri, Nov 16, 2007 at 03:50:20PM -0300, Jo??o Paulo Zavanela wrote:
> > How many fields is recomended to create a primary key?
> > I'm thinking to create one with 6 fields, is much?
>
> Normally a primary key would just be a single column.
Uhmm no. Normally a primary key is defined by the number of columns it
takes to determine naturally distinct values.
I would agree that if he is looking at 6 then he probably needs to
normalize further.
Sincerely,
Joshua D. Drake
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