Difference between ER diagram and EER diagram

database entity-relationship erd eer-model

shaki mandira · Mar 28, 2012 · Viewed 50.4k times · Source

What is the difference between ERD (Entity relationship diagram) and EERD (enhanced entity relationship diagram)?

Answer

You have relationships (image source)

example for an relationship

and attributes (image source)

example for an attribute

that can also be primary keys (image source)

example for an primary key

You have the same as with the ER model plus

specialisation

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partitioning (which are multiple specialisations)

generalisation

aggregation

keys are annotated differently:

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