Research My research focuses on developing efficient techniques to speed up data retrieval in a wide range of database applications (including parallel, distributed and peer-to-peer databases, image databases, video databases, high-dimensional databases, main memory databases, data streams and sensor networks, wireless and mobile databases). The broad set of techniques that I have contributed includes efficient memory- and disk-resident data structures (indexes), memory management schemes, efficient operator design and placement, and complex query optimization. I have also been working on database security and privacy.