Hello,
Of course using RDBMS directly will give the best results. Especially for large data volumes. But to have this feature in application layer is convenient.
Fritz Henglein has done some recent, interesting work in this area. His WGP paper (http://www.diku.dk/hjemmesider/ansatte/henglein/papers/henglein2010d.pdf) is a good place to start if you're interested. -Jeff --- This communication may contain confidential and/or privileged information. If you are not the intended recipient (or have received this communication in error) please notify the sender immediately and destroy this communication. Any unauthorized copying, disclosure or distribution of the material in this communication is strictly forbidden. Deutsche Bank does not render legal or tax advice, and the information contained in this communication should not be regarded as such.