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From: rm1122333@yahoo.com (Rob)
Newsgroups: comp.databases.theory
Subject: Newbie needs help with E/R model
Date: 5 Jun 2003 21:27:20 -0700
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I'm supposed to design a database for a movie rental shop using the
Entity/Relationship model. Problem is, I have to use between 5 and 10
entities, and between 10 and 20 relationships. I don't have any
practice at this, and I'm finding it hard to think of enough entites
and relationships. Here are the few

Here are the entities I've managed to come up with, with their
attributes listed.

Movies:
-sku (ID #)
-title
-year
-price 
-format (i.e., vhs, dvd)
-condition (i.e. rental, new for sale, used for sale)
-genre

Branch:
-store ID#
-phone no.
-address

Members:
-account no.
-name
-address
-phone no.
-credit card no.

Stars:
-name

I don't know how I could get closer to 10 entities. It took me long
enough to come up with 5! Am I maybe giving each entity too many
attributes?

Here are the relationships I thougt of:

rented(member, movie)
memberOf(member, branch)
starsIn(star, movie)

I still need 7 relationships. Any help or hints are greatly
appreciated!
Rob


StarsIn (movies, stars)