Augmenting UML with fact-orientation

The Unified Modeling Language (UML) is more useful for object-oriented code design than conceptual information analysis. Its process-centric use-cases provide an inadequate basis for specifying class diagrams, and its graphical language is incomplete, inconsistent and unnecessarily complex. For example, multiplicity constraints on n-ary associations are problematic, the constraint primitives are weak and unorthogonal, and the graphical language impedes verbalization and multiple instantiation for model validation. This paper shows how to compensate for these defects by augmenting UML with concepts and techniques from the Object Role Modeling (ORM) approach. It exploits data use cases to seed the data model, using verbalization of facts and rules with positive and negative examples to facilitate validation of business rules, and compares rule visualizations in UML and ORM. Three possible approaches are suggested: use ORM for conceptual analysis then map to UML; supplement UML with population diagrams and user-defined constraints; enhance the UML metamodel.