From Entity-Relationship Models to Role-Attribute Models
نویسندگان
چکیده
This paper is a short presentation of the SOM (Semantic Object Model) approach. SOM was created to fulfill two main objectives. The first objective is the revision of the traditional data modeling techniques in order to integrate them within an object oriented framework, without sacrificing the main object-oriented principles, namely encapsulation, extendibility and reusability. The paper advocates that the way data modeling concepts have been combined with object-oriented concepts does not reach that goal. The second objective is the improvement of data modeling techniques in order to make them able to model roles. Roles are an important real world aspect we think has not been suitably dealt with. This paper describes attributes and phases, the two main concepts of SOM. Attribute is the single concept used to model all static relationships and phases are thought to model roles. The paper also outlines the textual language (T-SOM) and the graphical language (G-SOM) used in SOM to describe conceptual schemes.
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