Enhanced-ER (EER) Model Concepts: Specialization and Generalization
EER is the high-level data model that incorporates the extensions to the ER Model. It is the diagrammatic technique to display the following concepts: Subclass and Superclass Specialization and Generalization Union and Category Aggregation Generalization It works on the principle of a bottom-up approach. In Generalization, lower-level functions are combined to form higher-level function which is called entities. This process is repeated further to make advanced-level entities. In the Generalization, process properties are drawn from particular entities and thus we can create the generalized entity. We can summarize the Generalization process as it combines subclasses to form a superclass. Example of Generalization – Consider two entities Student and Patient. These two entities will have some characteristics of their own. For example, the Student entity will have Roll_No, Name, and Mob_No while the patient will have PID, Name, and Mob_No characteristics. Now in this example Name a...
