Experiences running ogsa-dqp queries against a heterogeneous distributed scientific database

This paper explores the use of emerging Grid tech-nologies for the manipulation of a scientific dataset with complex schema. We focus on the potential of a well-known Grid middleware—OGSA-DQP—for querying such datasets. In particular, we investigate running OGSA-DQP queries against SQL Server and Oracle database to access data in a complex schema of a real scientific database—the Sloan Digital Sky Survey (SDSS) database. We used two common databases which support complex schemas and very large datasets: SQL Server and Oracle. The paper briefly provides the background information on the SDSS database. It then examines the running of a few OGSA-DQP queries and the query plans. Various join queries run successfully through OGSA-DQP after we optimized the im-plementation of some of the OGSA-DQP operations