Thanks for your response! Here's a little more information on what I'm trying to accomplish... I only want to update the records in COURSES where there is a matching NEW_COURSES record (based on the PK) AND where the exp_date has changed in NEW_COURSES. I don't want to touch any records where this criteria isn't met.

So in answer to your question in #2, I want to choose the NEW_COURSES row where the user_id, course_id, and start_date are matching in COURSES. Since start_date is part of the PK, I didn't think I had to do anything other than join on those three key fields to get the matching records. Am I not understanding your question correctly?

In answer to #3, if there is no matching row in NEW_COURSES then I don't want to do anything to the record in COURSES.

I really appreciate your help!