I.2 - The Entity-Relationship Model

The Entity-Relationship model was originally proposed by P. Chen (Chen P P, "The Entity-Relationship Model - Toward a Unified View of Data", ACM Transactions on Database Systems, Vol. 1, No 1, March 1976, pp 9-36) in 1976 as a way to unify the network and relational database views. Subsequently there has been a proliferation of theoretical extensions and practical applications of it.

The model is used routinely for system analysis and design. It has been coupled with process description methods, and has more recently being with Object Oriented programming. Every year there is an international conference devoted to it. It is simple enough that the basic concepts can be learned readily, yet sufficiently powerful for scientific and technical applications. Entity-Relationship is often abbreviated as ER. One refers therefore to the ER model.

I.2.1 - Basic ideas

I.2.2 - Attribute, Value, Domain, Entity Set

I.2.3 - Relationship, Relationship Set

I.2.4 - Roles of ESets in an RSet

I.2.5 - RSet properties

I.2.6 - The Entity-Relationship diagrams

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SF and PP - CERN PTG - ADAMO Reference Manual for Version 3.3 - 13 Dec 93