Re: Does Codd's view of a relational database differ from that ofDate& Darwin? [M.Gittens]
From: Alfredo Novoa <alfredo_novoa_at_hotmail.com>
Date: Mon, 06 Jun 2005 16:19:18 +0200
Message-ID: <5qm8a19q4nb9avbmhrik5nj5u35vujspsj_at_4ax.com>
Date: Mon, 06 Jun 2005 16:19:18 +0200
Message-ID: <5qm8a19q4nb9avbmhrik5nj5u35vujspsj_at_4ax.com>
On Mon, 06 Jun 2005 14:48:35 +0100, Paul <paul_at_test.com> wrote:
>I guess the other claim against NULLs is that they make things more
>complex and less intuitive, which is a more subjective point. You could
>argue that Darwen's method of avoiding NULLs is more complex that using
>NULLs in the first place.
Nulls undermine the conceptual integrity of the Relational Model which
is based in predicate logic.
A tuple with nulls does not match to a logical proposition.
This causes many problems. Some of them were pointed by Eric.
Regards Received on Mon Jun 06 2005 - 16:19:18 CEST