Lehrgebiet InformationssystemeFB Informatik |
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Versioning and Configuration Concepts in Non-Standard-Database-Systems
The representation and adequate manipulation of complex objects and complex object versions is a requirement inherent to many application areas. Especially in design applications adequate versioning and configuration concepts are crucial issues, since they allow for natural representations of design states. Thus, the principle of stepwise improvement, one of the major characteristics of design processes, is directly reflected. In this scenario, versions and configurations represent preliminary (w.r.t. the design goal) design information associated with a certain design quality and thereby establish a certain (meaningful) design state. In order to adequately support design applications we developed OVDM (the Object and Version Data Model) providing means for the representation and manipulation of explicit and apparent complex object versions and configurations. Basic concepts of OVDM are: complex objects, elementary objects, versions, links between objects as well as between versions, and configurations. Currently OVDM is structurally object oriented and the corresponding generic operations (OQL, the Object Query Language) allow for retrieval and manipulation of complex structures given as sets of versions (objects) connected by version (object) relationships as well as creation and selection of configurations. An object is considered as a set of its versions allowing the designer to use arbitrary versions for further processing, especially to step back in design history, to pick up an earlier version and to try another way to reach the local goal. Currently OVDM is completely conceptualized and implemented on top of the NDBMS PRIMA as well as on the object oriented DBMS ObjectStore. The latter implementation is named VStore.
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