Data Integration and Query Reformulation in Service-Based Grids

Abstract

This paper describes the XMAP data integration framework and query reformulation algorithm, provides insights into the performance of the algorithm, and about its use in implementing query processing services. Here we propose an approach for data integration-enabled distributed query processing on Grids by embedding the XMAP reformulation algorithm within the OGSA-DQP distributed query processor. To this aim we exploit the OGSA-DQP XML representation of relational schemas by applying the XMAP algorithm on them. Moreover, we introduce a technique to rewrite an XPath query into an equivalent OQL one. Finally, the paper presents a roadmap for the integration system implementation aiming at constructing an extended set of services that will allow users to submit queries over a single database and receive the results from multiple databases that are semantically correlated with the former one.