On the scope of relationships [CASE]

The concept of relationship scope is a valuable modelling concept with a variety of applications. A particular relationships´ scope expresses a constraint upon the entities which may validly be linked together by an instance of the relationship. The scoping of relationships has application to validation of reference relationships, imposing semantics upon the data not otherwise expressible directly by the data model. It can be applied to enrich the concept of composite entities. It can define the constraints necessary to direct relational table generation from entity and object oriented data models. It is one of a range of techniques contributing to our meta-CASE programme of managing the complexity of CASE tools by capturing as many aspects as possible through generic functionality parameterised for specific instances by values captured declaratively