A unification of concepts was presented at the "Trends in informationmodeling" seminar by Harm van der Lek. It illustrates the elegancy of the method FCO-IM by indicating a reduction of elements used in various data modeling methods.

ER, OO and UML allow users to data model using various concepts. They mention entitites and attributes and relationships between the entities. Methods like NIAM and ORM reduce the number of concepts to only two: Entities are handled as Object Types, where the relationships and attributes are handled as Fact Types.

The method FCO-IM takes this even a step further by stating 'Objects are in fact Facts'. FCO-IM allows Fact Types to be re-used as Object Types. By re-using a Fact Type as part of another Fact Type using natural language, a linguistic concept of nominalisation is introduced. This Fact re-use is graphically displayed as a fact surrounded by an ellipse. Using this representation it is easy to see that even object types remain fact types.

The unification of concepts is not a goal in itself, but makes model to model transformations easier and the data modeling method more elegant and transparent.

Below is a small diagram which shows the unification of concepts among different methods:

  • The footnote states that NIAM seperates Objects from Facts, whereas ORM mixes these.


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