Re: How long is long enough for primary key ?

From: DA Morgan <damorgan_at_psoug.org>
Date: Sat, 07 Oct 2006 09:35:33 -0700
Message-ID: <1160238931.907726@bubbleator.drizzle.com>

David Portas wrote:
> DA Morgan wrote:

>> Second Normal Form
>> tables do not have composite primary keys
>>

>
> I realize that your definitions are only informal but this one is a
> total mistake. 2NF does not imply the absence of composite keys.

Not informal at all. Perhaps this will clarify it.

"Second normal form (2NF) requires that data stored in a table with a composite primary key must not be dependent on only part of the table's primary key"

http://en.wikipedia.org/wiki/Database_normalization#Second_normal_form

-- 
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu
(replace x with u to respond)
Puget Sound Oracle Users Group
www.psoug.org

Received on Sat Oct 07 2006 - 11:35:33 CDT