Re: identity columns
From: Jan Hidders <hidders_at_uia.ua.ac.be>
Date: Mon, 21 Jan 2002 10:31:11 +0100
Message-ID: <3c4bdfb7$1_at_news.uia.ac.be>
Date: Mon, 21 Jan 2002 10:31:11 +0100
Message-ID: <3c4bdfb7$1_at_news.uia.ac.be>
"Lee" <lee_at_jamtoday.com> wrote in message
news:3nic4u0hiqiavitvnscqujba08i6764bb0_at_4ax.com...
>
> There may be good reasons why a particular proprietary system of
> creating a numerical psuedo column is full of fleas; but having a
> numerical, meaningless, system assigned unique primary key can be
> a good thing, in my experience.
>
> [...]
>
> There's a theoretical argument against them as follows:
>
> It aint 3NF:
> FirstName,Lastname in combination are unique in tje PERSON table. Your
> numerical PK AND your unique First NAme Last NAme mean in effect that
> you have two candidate keys, and shame on you!.
Why? Having two candidate keys is no problem in 3NF, or in any other of the standard normal forms.
- Jan Hidders