Chapter 5, Problem 4P

Explanation of Solution

Crow’s Foot ER diagram for Tiny College:

The following data model shows the solution for the given question.

Explanation:

• In the above data model, the “Employee” is the supertype entity of “Staff”, “Admin” and “Professor” subtypes and the primary key of “Employee” entity is “Emp_No”. The primary and foreign key of these subtypes are “Emp_No”. Another foreign key of “Professor” entity is “Dept_Code”.
• The overlapping constraint (o) is used as a category symbol. Here the “Employee” supertype entity has optional subtype entity.
• The “Student” table contains the details of students and every student can get advices from the “Staff” table...