That's crazy, why would it have the approach of "select all columns" when you might never need all of them? Could you create a view for it to select from instead?
Either way if someone told me a ETL supports only literally all the columns or nothing then I'd assume it was a MVP product to demonstrate the idea... not a production system.
Either way if someone told me a ETL supports only literally all the columns or nothing then I'd assume it was a MVP product to demonstrate the idea... not a production system.