Chapter $5$ Data Modeling with the Entity$-$Relationship Model

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A$.$ Draw an E$-$R data model for the Highline University Mentor Program Information System $($MPIS$).$ Use the IE Crow's Foot E$-$R model for your E$-$R diagrams. Justify the decisions you make regarding minimum and maximum cardinality.

Your model should track students, advisers, and mentors. Additionally, Highline University needs to track alumni because the program administrators view alumni as potential mentors.

Create separate entities for students, alumni, faculty advisers, and mentors.

AtHighlineUniversity, allstudents are required to liveoncampus and are assigned Highline University ID numbers and e$-$mail accounts in the format FirstName

$.$LastName@students.hu$.$edu. The student entity should track student last name, student first name, student University ID number, student e$-$mail address, dorm name, dorm room number, and dorm phone number.

At Highline University, all faculty advisers have on$-$campus offices and are assigned Highline University ID numbers and e$-$mail accounts in the format FirstName.

LastName@hu$.$edu. The faculty entity should track faculty last name, faculty first name, faculty University ID number, faculty e$-$mail address, department, office building name, office building room number, and office phone number.

Highline University alumni live off campus and were previously assigned Highline University ID numbers. Alumni have private e$-$mail accounts in the formal

FirstName.LastName@somewhere.com. The alumni entity should track alumnus last name, alumnus first name, alumnus former student number, e$-$mail address, home address, home city, home state, home ZIP code, and phone number.

Highline University mentors work for companies and use their company address, phone, and e$-$mail address for contact information. They do not have Highline University ID numbers as mentors. E$-$mail addresses are in the format

FirstName.LastName@companyname.com. The mentor entity should track mentor last name, mentor first name, mentor e$-$mail address, company name, company address, company city, company state, company ZIP code, and company phone number.

Create relationships between entities based on the following facts:

Each student is assigned one and only one faculty adviser and must have an adviser. One faculty member may advise several students, but faculty members are not required to advise students. Only the fact of this assignment is to be recorded in the data model $-$ not possible related data $($such as the date the adviser was assigned to the student$).$

Each student may be assigned one and only one mentor, but students are not required to have a mentor. One mentor may mentor several students, and a person may be listed as a mentor before he or she is actually assigned students to mentor. Only the fact of this assignment is to be recorded in the data model $-$ not possible related data $($such as the date the mentor was assigned to the student$).$

Each mentor is assigned to work and coordinate with one and only one faculty member, and each mentor must work with a faculty member. One faculty member may work with several mentors, but faculty members are not required to work with mentors. Only the fact of this assignment is to be recorded in the data model $-$ not possible related data $($such as the date the faculty member was assigned to the mentor$).$

Each mentor may be an alumnus, but mentors are not required to be alumni. Alumni cannot, of course, be required to become mentors.

B$.$ Revise the E$-$R data model you created in part A to create a new E$-$R data model based on the fact that students, faculty, alumni, and mentors are all a PERSON. Use the IE Crow's Foot E$-$R model for your E$-$R diagrams. Justify the decisions you make regarding minimum and maximum cardinality. Note that:

A person may be a current student, an alumnus, or both because Highline University does have alumni return for further study.

A person may be a faculty member or a mentor, but not both.

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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