OODB support for providing transparent schema changes
نویسندگان
چکیده
Schema updates on shared object-oriented databases (OODBs) are almost always prohibited because of the risk of making existing application programs obsolete when run against the modiied schema. We have proposed a solution approach, called Transparent Schema Evolution (TSE), that successfully addresses this problem by integrating schema evolution capabilities with object-oriented view facilities. In TSE, users interface with the OODB exclusively through their customized database view. In this paper, we identify key features required from OODB systems in order to provide such transparent schema change support, including multiple classiication, dynamic reclassiication, and exible restructuring. Such features are currently not supported by commercial OODB systems. We thus propose a novel object-oriented modeling paradigm that overcomes these limitations. Key concepts of the proposed solution include object-slicing techniques and object-oriented views. In this paper , we describe a prototype implementation of the object-slicing paradigm that we have built to demonstrate the feasibility of our TSE approach.
منابع مشابه
Capacity-augmenting Schema Changes on Object-oriented Databases: towards Increased Interoperability
The realization of capacity-augmenting schema changes on a shared database while providing continued interoperability to active applications has been recognized as a hard open problem. A novel three-pronged process, called transparent object schema evolution (TOSE), is presented that successfully addresses this problem. TOSE uses the combination of views and versioning to simulate schema change...
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