Database Management - Assignment #1
Objective:
This first assignment is designed to help you get some experience and
practice creating dependency diagrams.
Your task:
Draw the following three dependency diagrams:
1. (1 point) Draw a dependency diagram for the following situation:
Doctors prescribe drugs for patients. A given doctor can prescribe
many drugs for a certain patient. Many doctors can treat a patient.
Many doctors can prescribe the same drug to the same patient.
2. (2 points) Draw a dependency diagram for the following situation
describing a database application for a manufacturing parts company:
The Company manufactures automobile parts, which are of two kinds:
primitive parts and composite parts. Primitive parts are parts that are
not made up of other parts (they are indivisible). Examples of primitive
parts are spokes, nuts, bolts, washers, and screws. Composite parts
are those that are made up of other parts. An example of a composite
part is an engine that contains several parts such as pistons, cylinders,
rods, links, and cranks, assembled into one big unit (notice that the
piston itself could be a composite part, and so on). Each part has a
name, and a unique number (assigned by the company for
identification purposes). Primitive parts have a cost, while composite
parts have textual assembly instructions.
3. (2 points) Draw a dependency diagram for the following situation
describing a database application for a bookseller client who has the
following requirements: "I would like my customers to be able to
browse my catalog of books and place orders over the Internet.
Currently, I take orders over the phone. I have my mostly corporate
customers who call me and give me the ISBN number of a book and a
quantity. I then prepare a shipment that contains the books they have
ordered. If I don't have enough copies in stock, I order additional
copies and delay the shipment until the new copies arrive; I want to
ship a customer's entire order together. My catalog includes all the
books I sell. Most of my customers are regulars, and I have records
with their name, address, and credit card number. New customers
have to call me first and establish an account before they can use my
web site. On my new web site, customers should first identify
themselves by their unique customer identification number. Then they
should be able to browse my catalog and to place orders online."
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Database Management - Assignment #1
How to do this:
We are following the first step of the database design process
described in Lecture 1, on slides 22-30. Here is an example for how
the dependency diagrams are created.
1. Single-Valued (One-to-One) Dependencies
A person has one and only one birth date
PERSON
BIRTHDATE
A student has one and only one final grade for a course
FINAL
COURSE
GRADE
STUDENT
2. Multi-Valued (One-to-Many) Dependencies
A student can enroll in one or more classes
STUDENT
CLASSES
A person has zero or more sisters
SISTERS
PERSON
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Database Management - Assignment #1
3. Dependent and Independent Attribute Representation
Each appointment is with one or more clients. Each appointment with
one or more clients has a time. Each client has a single phone number.
APPOINTMENT
CLIENT
PHONE
NUMBER
TIME
Tools to use:
You can create your diagrams with a pen/pencil/marker/etc. on paper
or you can use a computer. It is probably easier to draw them on
paper but harder to edit them this way. If you are using a computer, I
can accept just about any file format including but not limited to, MS
Word, MS PowerPoint, MS Visio, MS Paint, most Paintbrush programs
and most graphic file formats. There are plenty of other options as
well. If you have questions about what program you can use, let me
know.
Grading criteria:
You will not be graded on your artistic abilities or talents. I want to see
your ideas and the dependencies you are able to see and form
between the objects in these scenarios. In most cases, there are many
different ways to show these relationships. Show them any way that
you want. If I can see them, you have accomplished your task.
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