Re: does a table always need a PK?

From: Alfredo Novoa <alfredo_at_ncs.es>
Date: 30 Aug 2003 11:59:22 -0700
Message-ID: <e4330f45.0308301059.7af31028@posting.google.com>

"Heikki Tuuri" <Heikki.Tuuri_at_innodb.com> wrote in message news:<FgK3b.436$st4.97_at_read3.inet.fi>...

> Yes, the above definition is exact and mathematical, because it describes a
> mathematical relation. It does not describe an 'RDBMS'. You cannot find a
> formal specification of Codd's rules below from it.
>
> http://www.cis.ohio-state.edu/~sgomori/570/coddsrules.html

Codd's rules are outdated. If you want a description of what an RDBMS is, I recomend you The Third Manifesto.

BTW, does anybody knows if Date and Darwen are considering to drop transactions in the next revision?

Regards
Alfredo Received on Sat Aug 30 2003 - 13:59:22 CDT