Re: c.d.theory glossary - RELATION
From: mAsterdam <mAsterdam_at_vrijdag.org>
Date: Fri, 30 Apr 2004 17:18:43 +0200
Message-ID: <40926e5d$0$562$e4fe514c_at_news.xs4all.nl>
>>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*.
Date: Fri, 30 Apr 2004 17:18:43 +0200
Message-ID: <40926e5d$0$562$e4fe514c_at_news.xs4all.nl>
x wrote:
> mAsterdam wrote:
>>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*.
> > Do some of the _facts_ about a (real or fantasized) world > tell something about _things_ in a (real or fantasized) world ?
I really don't know. Thinking out loud:
Say we have a history of axioms, and we would create a database
for searching purposes - we'ld probably have no use for it
if it didn't somehow represent persons or documents.
An empty database - would it qualify as a proper database? A database without any facts about things - would it qualify?
As I said: just thinking out loud. Received on Fri Apr 30 2004 - 17:18:43 CEST