The Tiny College Relational Diagram

A relational diagram for $4$ entities, course, class, enroll and student. The attributes for course are C R S underscore code, department underscore code, C R S underscore description and C R S underscore credit. The attributes for class are class underscore code, C R S underscore code, class underscore section, class underscore time, class underscore room, class underscore number and professor underscore number. The attributes for enroll are class underscore code, student underscore number and enroll underscore grade. The attributes for student are student underscore number, student underscore L name, student underscore F name, student underscore I N T$,$ student underscore D O B$,$ student underscore H R S$,$ student underscore class, student underscore G P A$,$ student underscore transfer, d e p t underscore code, student underscore phone and p r o f underscore number. In the first pair of entities, course and class, C R S underscore code, is the common attribute that links them together. In the second pair of entities, class and enroll, class underscore code is the common attribute. In the third pair of entities, enroll and student, student underscore number is the common attribute that links them together.Enlarge Image

Identify each relationship type and write all of the business rules.