Once you have made a set of changes to a ProDataSet, you then need to process them in a session that is connected to the database, and where the ProDataSet is attached to the Data-Sources. If you made the changes in a separate client session, such as our little Order window application, you need to pass the ProDataSet back to the server session. To minimize the amount of network traffic, in most cases you only want to send back those rows that were changed in some way, along with their before-images, leaving out all the rows in the after-tables that were not changed. There might be some exceptions to this, such as when the server-side business logic needs all the records in the original ProDataSet to do its processing, but in most cases you should do everything possible to limit the number of rows sent back across the network in a distributed application.