What is a subclass? When is a subclass needed in data modeling?
ASSIGNMENT The Enhanced Entity–Relationship (EER) Model 4.1. What is a subclass? When is a subclass needed in data modeling? 4.2. Define the following terms: superclass of a subclass, superclass/subclass relationship, IS-A relationship, specialization, generalization, category, specific (local) attributes, and specific relationships. 4.3. Discuss the mechanism of attribute/relationship inheritance. Why is it useful? 4.4. Discuss user-defined […]