Concept-Oriented Model: Classes, Hierarchies and References Revisited

We present the concept-oriented model (COM) and demonstrate how its three main structural principles — duality, inclusion and partial order — naturally account for various typical data modeling issues. We argue that elements should be modeled as identity-entity couples and describe how a novel data modeling construct, called concept, can be used to model simultaneously two orthogonal branches: identity modeling and entity modeling. We show that it is enough to have one relation, called inclusion, to model value extension, hierarchical address spaces (via reference extension), inheritance and containment. We also demonstrate how partial order relation represented by references can be used for modeling multidimensional schemas, containment and domain-specific relationships.