Prefetching is used to improve performance on cursors that only fetch relative 1 or relative 0. Two connection parameters let you change cursor prefetch defaults. PrefetchRows (PROWS) sets the number of rows prefetched; PrefetchBuffer (PBUF) sets the memory available to this connection for storing prefetched rows. Increasing the number of rows you prefetch may improve performance under certain conditions:
The application fetches many rows (several hundred or more) with very few absolute fetches.
The application fetches rows at a high rate, and the client and server are on the same machine or connected by a fast network.
Client/server communication is over a slow network, such as a dial-up link or wide area network.