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Computer

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Computer Terms

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Model vs Diagram

Entity-Relationship Model (ERM) - Entity-Relationship Diagram (ERD)

Created on Nov 27, 2020 · Last Modified on Jan 25, 2022

Both are used to represent interrelated things of interest (entities) in a specific domain of knowledge

  • Entity-Relationship Model (ERM) - was introduced by Peter Chen in 1976 (see first and second articles)
  • Entity-Relationship Diagram (ERD) - is a type of diagram used to represent ERM (e.g. Data Models)

ERD Notation Techniques

  • Crow’s Foot Notation
  • Chen Notation
  • IDEF1X Notation
  • Bechman Notation
  • Martin Notation
  • Min/Max Notation of Jean-Raymond Abrial in 1974
  • UML Class Diagrams