25SpCS157A Assignment 1

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2005 Spring
Prof. Sin-Min Lee
CS157A Assignment 1
Due: Feb. 10,2005 Thursday
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Readings: UandW Ch. 2.
Objective: The goal of this assignment is to provide you with some basic experience in database
design, and to introduce you to Entity Relationship diagrams as a modeling tool.
1) to learn the basic Entity Relationship (E-R) diagram components: entities, attributes and
relationships,
2) to develop data modeling skills,
3) to learn how to specify and use business rules to develop the components of an E-R
diagram,
4) to be able to interpret E-R diagrams as database blueprints
Develope an ER diagram of a library database. Show your entities (there should be 5-7 of
them) and relationships and at least two or three attributes per entity. Indicate minimum
and maximum numbers of items for both sides of each relationship. Possible Book entity
with the following attribute: TITLE, AUTHOR, PUBLISHER, COPY, and SUBJECT.
Naturally there are many other possible attributes. You must provide as much
information as possible: weak/strong entities, attribute types, cardinality constraints,
participation constraints (mandatory/optional/disjoint/overlapping), etc. Explicitly state
assumptions/choices that you make which may not be clear from your case description.
Cardinality constraints allow the restriction of the number of participating entities in
relationships. Remember that they are two possibilities to define cardinality constraints in
ER-diagram
(1) 1:1, 1:m or m:n notation
(2) (min,max) notation.
Turn in the following:

You have to provide (Part 1) the ER diagrams, (Part 2) an English description of each
entity and each attribute involved

The ER Diagram for your database design. You may want to use a drawing package to do
your drawing. One such package is Visio. Another way is to use Power Point. We have
provided a Powerpoint slide showing how to use it to create ER diagrams. Explore how
its work.
Submit your assignment electronically to:
CS157Asec2@yahoo.com
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