Question:

(a) Use the following business rules to produce the E-R diagram. You should clearly show all the minimum and maximum cardinality constraint on each side of the relationship.

King Car Enterprise runs a high quality car sales operation for which they provide a complete customer after sales service. In order to provide this service they keep records of the service needs of each type of car that they sell. This information includes how often a service is required in terms of the number of months between services and the distance covered. A car is serviced either when a predefined period has elapsed or the vehicle has covered a specific distance, whichever is the sooner.

A record is kept of the names and addresses of car owners. For each car that a customer owns a record is kept of the registration number of the car, the type of car, the date it was sold to the customer, the recorded distance traveled by the vehicle and the average distance undertaken by the owner per month.

When a customer makes a booking for a service a record is kept of the registration number of the vehicle and the date for which the service has been booked. Finally, a record is kept of the service history of a car which includes the dates upon which the vehicle was serviced, the registration number of the vehicle and the vehicle mileage when the service was carried out.

The primary goal of the computer system is to be able to send reminders to customers that a vehicle they own is due for service.

(b) Map the ERD produced above into its equivalent Relational Schema.