文摘
While data within an organization has become increasingly dispersed, the need for a consolidated information view has remained important. Consequently, data integration methods have been the topic of much of today's research. This dissertation concentrates on the development of a feasible knowledge representation and query processing algorithm that create a mediator to process the semantic real-world knowledge of typical application queries. The Virtual Data Integrator (VDI) is an object-oriented data mediator that has been developed as one such solution.;VDI is a software tool that transparently integrates various related databases into a virtual view of an integrated computing environment. The Virtual Data Integrator's knowledge representation (VDIR) is used to portray a global schema of the different database models, and the Virtual Data Integrator's three step query processor (VDIP) semantically translates a query written in terms of one database schema into all of the applicable queries for the other databases. The components, development techniques, underlying foundation for VDI are detailed and illustrated in an example.