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Re: c.d.theory glossary - RELATION

From: mAsterdam <mAsterdam_at_vrijdag.org>
Date: Fri, 30 Apr 2004 16:12:09 +0200
Message-ID: <40925ec4$0$574$e4fe514c@news.xs4all.nl>


x wrote:
> Laconic2 wrote:

>>I would have said that "An entity is DESCRIBED BY a set of attributes."
>>
>>I think REPRESENTED is too strong.

>
> It was not my choice.
> As I said, I found that on a web page about ER modeling.
>
> Do you also think REPRESENTED is too strong in the context of
> relational model (not in the context of ER modeling) ?

This is where a difference come in:

In ER-modelling the parts of the model are abstractions of (real or fantasized) world _things_ and associatons between them, vs.
the relation values in a relational model represent _facts_ (or beliefs) about a (real or fantasized) world.

In short
RM.REPRESENT yes, *facts*.
ER.REPRESENT yes, *things*.

Just 2 Ec in trying to make sense of this mess. Received on Fri Apr 30 2004 - 09:12:09 CDT

Original text of this message

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