$228$

Part $2$ Database Design

A person may be a faculty member and an alumnus.

A person may be a mentor and an alumnus.

A current student cannot be a mentor.

Each mentor may be an alumnus, but mentors are not required to be alumni.

Alumni cannot, of course, be required to become mentors.

C$.$ Extend and modify the E$-$R data model you created in part B to allow more data to be recorded in the MPIS system. Use the IE Crow's Foot E$-$R model for your E$-$R diagrams. Justify the decisions you make regarding minimum and maximum cardinality. The MPIS needs to record:

The date a student enrolled at Highline University, the date the student graduated, and the degree the student received.

The date an adviser was assigned to a student and the date the assignment ended.

The date an adviser was assigned to work with a mentor and the date the assignment ended.

The date a mentor was assigned to a student and the date the assignment ended.

D$.$ Write a short discussion of the difference between the three data models you have created. How does data model B differ from data model A$,$ and how does data model $C$ differ from data model $B?$ What additional features of the $E-R$ data model were introduced when you created data models B and C$?$