Re: Does Codd's view of a relational database differ from that ofDate& Darwin? [M.Gittens]
From: paul c <toledobythesea_at_oohay.ac>
Date: Mon, 06 Jun 2005 15:02:17 GMT
Message-ID: <ZzZoe.1585552$Xk.1296585_at_pd7tw3no>
>
>
> Nulls undermine the conceptual integrity of the Relational Model which
> is based in predicate logic.
>
> A tuple with nulls does not match to a logical proposition.
>
> This causes many problems. Some of them were pointed by Eric.
>
>
> Regards
>
Date: Mon, 06 Jun 2005 15:02:17 GMT
Message-ID: <ZzZoe.1585552$Xk.1296585_at_pd7tw3no>
Alfredo Novoa wrote:
> 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
>
i'm an admirer of Date's but i have to say i like your answer. no Latin to look up, either.
p Received on Mon Jun 06 2005 - 17:02:17 CEST