>Thanks, Edward
>UNION of these 3 INs works perfectly in my case. But back to my SELECT: What do you think is different between first and second run of my original SELECT???
Again, cannot say by sure :). However, I remember some reported bugs about too many (NOT) IN(s) in SELECT. They just cheat internal optimization somehow. It's always relevant to split complex select statement to chain of simpler ones.
Edward Pikman
Independent Consultant