OGSA-WebDB: an OGSA-based system for bringing Web databases into the grid

An OGSA-based system, OGSA-WebDB, is proposed, which enables local database applications to query Web databases using a standard database query language (SQL). OGSA-WebDB consists of two main components: proxy databases and a mediator. Proxy databases represent the desired Web databases while the mediator acts as an interface between the proxy databases and the Web databases. The mediator accepts an SQL query from local applications and transforms the query into one or more Boolean conditions that are then sent to the target Web databases. The mediator processes the SQL query in parallel, taking into account the characteristics of the Web databases. Experimental results revealed that the query processing time is so small that it can be ignored for timing considerations. The system has been fully implemented on top of Globus Toolkit and OGSA-DAI software components.