Describe enhanced ER model with the help of example.

Describe enhanced ER model with the help of example. 
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Answer :

Enhanced ER is a high-level data model that incorporates the extensions to the original ER model. It is created to design more accurate database schemas. EER reflects data properties and constraints more precisely. It also includes more complex requirements than traditional application. 


It is a diagrammatic technique for displaying the following concepts

  • Sub Class and Super Class
  • Specialization and Generalization
  • Union or Category
  • Aggregation
These concepts are used when they comes in EER schema and the resulting schema diagrams called as EER Diagrams.
For example: Square, Circle, Triangle are the sub class of Shape super class. 
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