Re: Peter Chen and Charles Bachman
Date: Wed, 5 May 2004 07:41:20 -0500
Message-ID: <c7ando$tol$1_at_news.netins.net>
"Leandro Guimarães Faria Corsetti Dutra" <leandro_at_dutra.fastmail.fm> wrote
in message news:pan.2004.05.05.02.38.23.931293_at_dutra.fastmail.fm...
> Em Tue, 04 May 2004 17:16:28 -0500, Dawn M. Wolthuis escreveu:
>
> >> Diagrams aren't models...
> >
> > I'll accept that diagrams, in themselves, are not full mathematical
> > theories, but models they often are, it seems to me. What is your
> > definition of "model" (as a noun)?
>
> A model must include all aspects of the database, or it will
> be only a draft.
With the number of dialogs we have that include information relevant to databases, but "orthogonal" to relational theory, my conclusion is that by your definition relational theory is not a model -- is that correct?
>
> A diagram can hardly be expected to represent, say, all
> constraints in a database.
>
> Not to mention their maintenance tends to become
> counterproductive as the database grows in complexity and size.
>
> They are nice as drafts in the early stages of modelling and
> for presentation.
>
>
> --
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Received on Wed May 05 2004 - 14:41:20 CEST