Associate additional columns with an external query
 

I would like to associate some additional data with some information that I
get by using an external query in excel. Whenever I do the refresh, my data
columns don't always line up. Is there a way to tie the data to a particular
key.

For example, I have a customer number and their name that come from a
database. I then add an additional column called comments. I then requery
the database and my data no longer lines up if more customers were added.