Re: c.d.theory glossary - RELATION
Date: Fri, 30 Apr 2004 18:01:21 +0300
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"mAsterdam" <mAsterdam_at_vrijdag.org> wrote in message
> 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.
If you look in a dictionary you'll find: Fact: someTHING that exists (or happened).
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