I often emphasize the importance of logic in T-SQL problem solving. In recent columns, I've given you a T-SQL puzzle and a purely logical puzzle to help you improve your logic skills. This article's T-SQL puzzle will stretch your T-SQL skills as you try to derive the best solution. In the sidebar "The Logical Puzzle," page 30, I present a new logic problem to try. Do your best to solve the puzzles yourself before looking at my solutions. If the trivial and intuitive approaches you come up with seem cumbersome, try to be creative and think outside the box.