Thanks. "Strange" - Yes I thought so too. So I thought why not test it anyway as I didn;t think it was valid. I have an idea on paper from someone else(that I don't fully understand yet hence this post) and they documented this approach. Just to compare notes, Why do you consider it to be strange?
Hi Marc, it's strange, because the update is based on two columns and one of those is also used within the where-condition. What kind of summable information is hidden within that column? I simply can't imagine any real usage for that :-)