>Since I've got data running through, and it's 4am and I'm a glutton I'll try to explain what I'm doing :) I want to flag records where the are no occurances of 2 different f1's to a f2 and vice versa
>
>lets put letters in f1 and numbers in f2
>

>f1 - a a a b b c d e f g g g h h h h i
>f2 - 1 1 1 2 3 4 4 5 6 7 7 8 9 9 9 9 9
>f3 - 0 0 0 1 1 1 1 0 0 1 1 1 1 1 1 1 1
>

>"a"'s only match 1's in f2 so they do not get flagged
>"b"'s match a 2 and a 3 so it gets flagged
>"c" only matches a 4 however 4's match "c" and "d" so it gets flagged
>etc etc
>
>hope that explains it better, as I said I'm not looking for a solution to the above, I already have that, it's just what I was doing when I found that an update fails doing the same query where a select is sucessfull, that's what puzzles me.

What is your SELECT which worked?