river1 - Monday, April 16, 2018 9:09 AM
The better solution (IMO) is to have a first step which checks the file to determine whether it contains the troublesome column & set a Boolean package variable accordingly, and then to use precedence contraints to control which DF gets executed.
If you haven't even tried to resolve your issue, please don't expect the hard-working volunteers here to waste their time providing links to answers which you could easily have found yourself.