Advances in Databases: Concepts, Systems and Applications 12th International Conference on Database Systems for Advanced Applications, DASFAA 2007, Bangkok, Thailand, April 9-12, 2007. Proceedings - Kotagiri, Ramamohanarao; Krishna, P. Radha; Mohania, Mukesh; Nantajeewarawat, Ekawit (Springer Berlin Heidelberg, 2007)