Release 10.1A: OpenEdge Development:
ProDataSets

Summary

That’s all there is to the data access procedure. To summarize:

It defines the Data-Sources for the ProDataSet tables.
It provides any needed field mapping from database to ProDataSet.
It defines and attaches the FILL logic needed for calculations.
In short, it handles everything that needs to be aware of the database specifics and nothing at all that happens to the ProDataSet after it’s filled.