David
What types of operations are you performing on the data once it is on the client machine ?

Are you using something like a Fill() method to fill your database.

If so I might recommend using a data reader which will process through each record one at a time. Readers are one way mechanisms that only read forward. You do have access to each column of data via this mechanism but you cannot go backwards.

We had some rather large SQL to XML exports to do and by using a data reader we were able to create a 1.1GB file in 5 minutes. We had comparable amounts of records and a very large record structure.

Rodman