BigCheese,
I had that error when I first tried that query and it was just because I had 32 taken up already by an old hack I wasn't even using anymore and forgot about. I went to
www.yoursite/forums/admin/setting.php page and deleted that group...freeing up 32. I ran the query again and it was a success.
Maybe this is your reason too? If not, sorry to confuse ya. And like Hellsatan said...there should be a \ between " Who " and " 's " as I noticed as well.