Changing the definition of data source in generic extraction!

Hi,

Is there any way could we change the definition of generic data source by means of changing the definition extraction from database view to extraction from Function module?

We have an extractor which is using View for the generic extraction.Now the logic being complicated of appending two more fields view extraction is not good enough.

And i want to change the definition of the data source as extraction from function module.

How can i accomplish this in RSO2 screen?

Thanks,

Ravi