Polymorphism association in Sybase PowerDesigner

Question

I want to make polymorphism between 4 Entities in Sybase PowerDesigner tool, but there is no explanation how to do this in conceptual data model.

Can you help me with this?

Answer 1

I think that term "polymorphism" is applicable to Object Oriented Model but not to Conceptual Data Model.

If you want to describe 4 entities with the same behavior you should generate OOM model from CDM model or use inheritance in CDM. But "inheritance" is not the same as "polymorphism".

Answer 2

I'm not sure that CDM is the best practice for "logical/conceptual" analysis. Some years ago I started using OOM Analysis Model instead of CDM. You are be able to use UML notation with OOM Analysis Model but this model is not associated with a concrete language. This kind of model provides the same functionality as CDM, but you use UML-notation. As a result, there are no problems with such OOP terms as inheritance and polymorphism. You are also able also to generate PDM or OOM(Java/C#/...) from OOM Analysis.