Thank you Marc.  The pool size confused me because the help states for business operations it should be 1.  Is there a max that this should not be over?  And does it affect the processing of the server (using up more memory, etc).

And now that I re-read the help, it states 1 is the default value.  

That was the problem.  Many thanks, Robert.  Who would have thought you cannot put context variables in the SQL?

1. Luckily, no.  This workflow will be instantiated after both files have been received.  

2. It's actually more than just tracking number.  Serial number, part number and a few others.  The tracking file will contain data for all POs in the main file.

3. The tracking file will be named the same thing daily, containing tracking information for all POs in the main file.  There are not multiple files (for either one).