The NewKey() SP is only is called when client application starts. It creates a unique key and returns it to client. Subsequent keys are generated locally by concatenating keys created on client with the one returned from SP to form new unique keys. The benefit is each time you add a record you don't have to make an additional round trip to server to get a new key.

My application will potentially create a lot of records in a user session so this saves a lot of annoying round trips to server. Updates (insert, update, delete) are done in batch loop. Since all processing is done on client, user only waits during an update.

Charlie