Following is an ER Diagram for car rental rental. It illustrates the various entities involved within the system using rectangular boxes along with the relationship among the entities using diamond-like shapes. It also describes the attributes associated with each entity using oval shapes.Here oval shapes with multi-borders represent a multivalued attribute, and a multi-border rectangular shape represents weak entities present within the car rental system.In the following diagram for the car rental system, the various entities involved consist of the: Customer, employee, vehicle, reservation and rent. The ER diagram describes the characteristics of these entities along with the interrelationship among them.
