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Re: ERD attributes or?

From: Arto V. Viitanen <av_at_cs.uta.fi>
Date: Thu, 18 Dec 2003 10:26:13 +0200
Message-ID: <wellpaedlm.fsf@siwenna.cs.uta.fi>


>>>>> "shannon" == shannon <shannon_at_nolunchmeat.com> writes:

 shannon> whats up, I am just tryin to learn DB, if you can't help then thats  shannon> okay,

 shannon> Alan wrote:

 >> Read your textbook. No one here will do your homework for you.  

>>How do i treat class, departments and degree?
>>
>>Can they be attributes of student, or something else..?

What Alan (I guess) meant is that books tell, that it depends. If you have no other information of the degree but its name, then it is an attribute. If you have lots of information, like how many points (we use term study week) it lasts, when the degree was given etc., then it is an entity.

I guess one approach is to make all things entitites, and then collect those together you can. Another is to make a one big entity (or universal relation in relation system), and split it to smaller ones.

But as Alan said, read your textbook.

-- 
Arto V. Viitanen				                  av_at_cs.uta.fi
University of Tampere, Department of Computer Sciences
Tampere, Finland				      http://www.cs.uta.fi/~av/
Received on Thu Dec 18 2003 - 02:26:13 CST

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