Although generally the migrating to DB2 9 done recently at UBS was a very smooth experience, we did encounter a couple of performance degradations due to changes in access path. One of these where particular troublesome, because in general there was a need to have REOPT(ALWAYS) enabled for statements in the affected package, but for the trouble statement we needed to have an OPTHINT to fix the access path to always be the same.
After a bit of investigation and searching the Internet, we stumbled over following presentation from the IDUG Tech Archives: "Hint, Don't 'Trick', Your Troublesome Access Paths" and bingo on slide 44. There we had the recipe for addressing the challenge at hand. There is a saying within the IDUG Community that an IDUG Tech Conference can pay for itself, if you would pick up somewhere between 5-10 solutions to issues you have in your own shop, and here we got it all free thanks to these archives being made available to us.