UML data models from an ORM perspective : Part 8

This paper is the eighth in a series of articles examining data modeling in the Unified Modeling Language (UML) from the perspective of Object Role Modeling (ORM). Part 1 discussed historical background, design criteria for modeling languages, object reference and single-valued attributes. Part 2 covered multi-valued attributes, basic constraints, and instantiation using UML object diagrams or ORM fact tables. Part 3 compared UML associations and related multiplicity constraints with ORM relationship types and related uniqueness, mandatory role and frequency constraints, as well as how associations may be instantiated. Part 4 contrasted ORM nesting with UML association classes, ORM coreferencing with UML qualified associations, and ORM exclusion constraints with UML or-constraints. Part 5 discussed subset and equality constraints. Part 6 discussed subtyping. Part 7 discussed value, ring and join constraints. Part 8 covers some recent updates to the UML standard, then discusses aggregation.