Object configurations in software engineering databases

We consider the logical organization of database support for software engineering applications, which has to cope with such requirements as the adequate support of object composition and versioning, the derivation of (consistent) configurations, and the provision of application-specific transactions. A new approach to the organization, manipulation and management of multiversion objects in CASE databases is described and investigated, which clearly distinguishes four relevant concepts: documents, versions, configurations and databases. The approach is formally made precise using the concept ofAND/OR graphs, which renders it possible to cast operations on any of the concepts in terms of graph operations. The levels of abstraction distinguished and maintained throughout the exposition give rise to an appropriate transaction concept: transactions involve graph operations on specific types of objects only; conflicts between transactions can thus be easily identified, and consistency of objects is easily maintained.