Newbie needs help with E/R model

From: Rob <rm1122333_at_yahoo.com>
Date: 5 Jun 2003 21:27:20 -0700
Message-ID: <9d11b6b.0306052027.60762b58_at_posting.google.com>

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) Received on Fri Jun 06 2003 - 06:27:20 CEST