On the value of commutative diagrams in information modelling

  • Michael Johnson
  • C. N. G. Dampney
Part of the Workshops in Computing book series (WORKSHOPS COMP.)


Category theory has been widely used in computer science, but usually in a very sophisticated manner. This paper argues that elementary category theoretic notions can have important value in the “real world” of software engineering. Perhaps the most elementary categorical notion is that of commutative diagram. Drawing on experience from several applications of category theory to information modelling in major business enterprises we show how commutative diagrams have been used to develop new methodologies in ER-modelling, constraint specification and process modelling. They also suggest new but as yet untested techniques for information model partitioning and information system architecture. The methodologies described here have a firm theoretical basis using the recently isolated theory of lextensive categories and this basis is briefly outlined.


Commutative Diagram Static Constraint Information Model Query Language Category Theory 
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Copyright information

© British Computer Society 1994

Authors and Affiliations

  • Michael Johnson
    • 1
  • C. N. G. Dampney
    • 1
  1. 1.School of Mathematics and ComputingMacquarie UniversitySydneyAustralia

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