Entity-Relationship Model in database management system free pdf download
1. Entity Sets:-An entity is a “thing” or “object” in the real world that is distinguishable from all other objects. For example, each person in an enterprise is an entity. An entity has a set of properties, and the values for some set of properties may uniquely identify an entity. 2. Attribute: - An attribute of an entity set is a function that maps from the entity set into a domain.