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Re: c.d.theory glossary - RELATION

From: x <x-false_at_yahoo.com>
Date: Fri, 30 Apr 2004 10:38:52 +0300
Message-ID: <409201d7$1@post.usenet.com>

"mAsterdam" <mAsterdam_at_vrijdag.org> wrote in message news:4091691c$0$564$e4fe514c_at_news.xs4all.nl...
> Laconic2 wrote:
> [language mapping]
>
> An _entity_ in ER modelling usally gets mapped to a _table_
> in a SQL db - that would be^H^Hrepresent a _relation_ in
> relational, no? A _relation_(ship) mostly maps to a foreing
> key in the child table referring the parent. The use of
> 'association' instead of 'relation' in ER (or would it be EA,
> ERA being Entity-Relationship-Attribute, hmmm... not good)
> never really cought on.

I found this on a web page about ER modelling: "The question of what constitutes an entity and what constitutes an attribute depends mainly on the structure of the real world situation being modeled, and the semantics associated with the attribute in question"

"An entity is REPRESENTED BY (NOT is ) a set of attributes"

May I suggest that entities get mapped to a field or to a set of fields and a relation(ship) to a table ?

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Received on Fri Apr 30 2004 - 02:38:52 CDT

Original text of this message

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