Question One

Design an ER diagram for the following Dental Clinic database. Your diagram should have all the needed details. You may make any reasonable assumptions but you have to state them clearly.

 

1. Design an Entity Relationship (ER) Model to represent the above requirements.   (2 Marks)
2. Convert the ER Diagram that presented in part-1 to Rational Schema. (2 Marks)

Question Two

Explain and distinct between disjoint and overlapping constraints. (0.5 Mark)

 

Illustrate your answer with suitable examples for each constraint. (0.5 Mark)

 

Question Three

Define Cardinality Ratios for binary relationship? What are possible Cardinality Ratios for Binary Relationship? Suppose in SEU, there are some departments consist of many employees.                ( 1  Mark)

What is the cardinality ratio for DEPARTMENT:EMPLOYEE? (0.5 Marks)

Question Four

In SEU, identify Cardinality ratios between the following entities:

 

     Entity 1                      Cardinality Ratio                           Entity 2

 

CLASSROOM                 ______________                            PODIUM

STUDENT                       ______________                            CLASS

INSTRUCTOR                ______________                            TECHNICAL STAFF

ROOM                             ______________                            BRANCH

STUDENT                       ______________                            TEACHER

INSTRUCTOR                ______________                             DEAN