T02 DB

Tutorial 2
Topic: Data Models

1. What is a data model? Give an example
Relatively simple representations of complex real-world data structures via graphical representation.

2. Discuss the importance of business rules in data modeling.
Help standardize the company’s view of the data. Allow designer to understand business process. It also use as communication tool.
3. Consider the scenario described by the statement “A customer can make many payments, but each payment is made by only one customer”. Draw a data model to represent this scenario.

4. List the business rules depict by the Entity Relationship Diagram below.

a professor can give advice to many student, but student is advised by 1 professor
A professor can teaches many classes, but a class is teach by 1 professor

5. The following are business rules for ABC Company.
Each sales representative writes many invoices; each invoice is written by one sales representative.
Each sales representative is assigned to one department; each department has many sales representatives.
Each customer can generate many invoices; each invoice is generated by one customer.

a) Draw Entity Relationship Diagram to represent the business rules. b) Draw Object-Oriented Data Model to represent the business rules.