Re: Newbie question about db normalization theory: redundant keys OK?

From: Tony Rogerson <>
Date: Fri, 14 Dec 2007 18:14:41 -0000
Message-ID: <fjuh8s$bhn$1$>

> There are two ways I would answer this. The first says that email
> address isn't a natural key -- it doesn't uniquely define a person any
> more than hair color does. The second is that the natural key hasn't
> changed, the entity -- a mailbox on a mail server -- has changed.

Absolutely - so we need to use something that won't change - an artificial key.

Tony Rogerson, SQL Server MVP
[Ramblings from the field from a SQL consultant]
[UK SQL User Community] 
Received on Fri Dec 14 2007 - 19:14:41 CET

Original text of this message