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 and […]
Discuss the main categories of data models. What are the basic differences among the relational model, the object model, and the XML model?
Classification of Database Management Systems 2.1. Define the following terms: data model, database schema, database state, internal schema, conceptual schema, external schema, data independence, DDL, DML, SDL, VDL, query language, host language, data sublanguage, database utility, catalog, client/server architecture, three-tier architecture, and n-tier architecture. 2.2. Discuss the main categories of data models. What are the […]