Database fundamentals
DATABASE FUNDAMENTALS
Week10- TUTORIAL 10: Chapter 11
Chapter 11: Conceptual, Logical and Physical Database Design
1. Create the initial ER diagram for a car dealership. The dealership sells both new and used cars, and it operates a service facility. Base your design on the following business rules:
a. A salesperson can sell many cars, but each car is sold by only one salesperson.
b. A customer can buy many cars, but each car is sold to only one customer.
c. A salesperson writes a single invoice for each car sold.
d. A customer gets an invoice for each car(s) he buys.
e. A customer might come in only to have a car serviced; that is, one need not buy a car to be classified as a customer.
f. When a customer takes in one or more cars for repair or service, one service ticket is written for each car.
g. The car dealership maintains a service history for each car serviced. The service records are referenced by the car’s serial number.
h. A car brought in for service can be worked on by many mechanics, and each mechanic can work on many cars.
i. A car that is serviced may or may not need parts. (For example, parts are not necessary to adjust a carburetor or to clean a fuel injector nozzle.)
1