Systems Analysis Chapter 3 and 4

Week 2 Problems and Exercises Chapters 3 and 4

2. A performance ve-+nue hosts many concert series a year. Performers have a name and perform several times in a concert series (each constituting a performance with a different date). Concert series have one or more performers and have a name and a specified seating arrangement. A concert series is held in one (and only one) of several concert halls, each of which has a room number. Represent this situation of concerts and performers with an E-R diagram.

Performance

Performer ID

Series ID

Date

Performance

Performer ID

Series ID

Date

Performer

Performer ID

Name

Performer

Performer ID

Name

Concert Series

Series ID

Name

Seat Setup

Concert Series

Series ID

Name

Seat Setup

Concert Hall

Concert Hall ID

Room #

Concert Hall

Concert Hall ID

Room #

4. Consider the E-R diagram in Figure 7-7.

a. What is the identifier for the CERTIFICATE associative entity? The combination of Employee_ID and course_name.

b. Now, assume that the same employee may take the same course multiple times, on different dates. Does this change your answer to part a? Why or why not?  If an employee is permitted to take the course multiple times, then the identifier is no longer unique.   Another identifier will need to be specified. This identifier could be a combination of Employee_ID, course_name and the date.

c. Now, assume we do know the instructor who issues each certificate to each employee for each course. Include this new entity in Figure 7-7 and relate it to the other entities. How did you choose to relate INSTRUCTOR to CERTIFICATE and why?  The inclusion of the INSTRUCTOR would make this a ternary relationship.  The INSTRUCTOR would have a mandatory one cardinality. The identifier for the CERTIFICATE associative would be a combination of Employee_ID, Course_Name, InstructorID, and possibly Date.

1. Pine Valley Furniture

Development work on Pine Valley Furniture’s new Customer Tracking System...