ER-Diagram and EER-Diagram
Medinah Transport dealership sells Proton, Ford, Honda and Toyota. The dealership keeps the cars information such as vehicle number, list price, chassis number, made (eg. Honda, Toyota), model name (eg. Civic, Camry) and year. They also keep information about all sales they have made (for instance, invoice number, buyer’s name, data of purchase and amount paid for the car). In order to contact the buyers in the future, the dealership also keeps their telephone number and address. Some buyers bought more than one car. For statistical purposes, the buyer’s gender and age are also captured. Dealer also needs to know the staff who sold the cars to the buyers such as their staff ID, name, phone number, gender, date of birth, address and basic salary. The dealership has two types of staff - sales agent and admin. Sales agent will have sales quota, basic salary and sales commission from selling cars. While admin staff will receive basic salary and overtime (based on his/her overtime rate). Medinah Transport has three dealerships all over town. The branch is identified by a unique branch number, address and telephone number. Each staff will be assigned to a particular branch.
Based on the information given about Medinah Transport, create a single integrated Entity Relationship Diagram or EER-Diagram using the class notation diagram from UML. In your diagram, you should identify all the entities, attributes, primary key, relationship, and multiplicity constraints.