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chaPter 7 • Using Data Flow Diagrams 207

8. Draw a logical child diagram for Diagram 0 in Problem 7 for the process that adds a new customer if
he or she is not currently in the database (that is, has never ordered from Perfect Pizza before).
9. Draw a physical data flow diagram for Problem 7.
10. Draw a physical data flow diagram for Problem 8.
11. Partition the physical data flow diagram in Problem 7, grouping and separating processes as you
deem appropriate. Explain why you partitioned the data flow diagram in this manner. (Remember
that you do not have to partition the entire diagram, only the parts that make sense to partition.)
12. a. Draw a logical child diagram for Process 6 in Figure 7.17.
b. Draw a physical child diagram for Process 6 in Figure 7.17.
13. Draw a physical data flow diagram for Process 1.1 in Figure 7.18.
14. Create a context diagram for a real estate agent trying to create a system that matches buyers with
potential houses.
15. Draw a logical data flow diagram showing general processes for Problem 14. Call it Diagram 0.
16. Create a context-level diagram for billing in a dental office. External entities include the patients and
insurance companies.
17. Draw a logical data flow diagram showing general processes for Problem 16. Call it Diagram 0.
18. Create an event response table for the activities listed for World’s Trend order processing system.
19. Create a use case for the list of seven processes for the World’s Trend order processing system.
20. Create a CRUD matrix for the files of World’s Trend.
21. Use the principles of partitioning to determine which of the processes in Problem 18 should be
included in separate programs.
22. Create a physical data flow child diagram for the following situation: The local running club holds meet-
ings once a month, with informative speakers, door prizes like pre-paid entry fees for races, designer
running gear, and so on, and sessions for special interest groups (people who want to coach, people who
want to run marathons, those who want to get fit, and so on). A laptop computer is taken to the meetings
and is used to add the names of new members to the group. The diagram represents an online process
and is the child of Process 1, ADD NEW MEMBERS. The following tasks are included:
a. Key the new member information.
b. Validate the information. Errors are displayed on the screen.
c. When all the information is valid, a confirmation screen is displayed. The operator visually con-
firms that the data are correct and either accepts the transaction or cancels it.
d. Accepted transactions add new members to the MEMBERSHIP MASTER file, which is stored on
the laptop hard drive.
e. Accepted transactions are written to a MEMBERSHIP JOURNAL file, which is stored on a sec-
ond hard drive.

Group Projects

1. Meet with your group to develop a context-level data flow diagram for Maverick Transport (first
introduced in Chapter 4). Use any data you have subsequently generated with your group about
Maverick Transport. (Hint: Concentrate on one of the company’s functional areas rather than try to
model the entire organization.)
2. Using the context-level diagram developed in Group Project Problem1, develop with your group a
level 0 logical data flow diagram for Maverick Transport. Make any assumptions necessary to draw
it. List them.
3. With your group, choose one key process and explode it into a logical child diagram. Make any
assumptions necessary to draw it. List follow-up questions and suggest other methods to get more
information about processes that are still unclear to you.
4. Use the work your group has done to date to create a physical data flow diagram of a portion of the
new system you are proposing for Maverick Transport.

Selected Bibliography

Ambler, S. W., and L. L. Constantine (Eds.). The Unified Process Inception Phase: Best Practices for
Implementing the UP. Lawrence, KS: CMP Books, 2000.
Gane, C., and T. Sarson. Structured Systems Analysis and Design Tools and Techniques. Englewood Cliffs,
NJ: Prentice Hall, 1979.
Hoffer, J. A., M. Prescott, and H. Topi. Modern Database Management, 9th ed. Upper Saddle River:
Prentice Hall, 2009.