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Entity Relationship
Found 2 free book(s)
The Extended Entity Chapter 5 Relationship Model
media.lanecc.eduThe Extended Entity Relationship Model • Result of adding more semantic constructs to original entity relationship (ER) model • Diagram using this model is called an EER diagram (EERD) • Combines some of the Object-oriented concepts with Entity Relationship concepts. 2 Entity Supertypesand Subtypes • Entity supertype –Generic entity ...
Exercises - web.cs.ucla.edu
web.cs.ucla.eduan entity set to represent an object, and deciding between an entity set and relationship set, in˜uence the accuracy with which the real-world concept is expressed. If the right design choice is not made, inconsistency and/or loss of information will result. A model which can be implemented in an ef˚cient manner is to be preferred for obvious ...