You can make use of Recursive CTEs (if you have 2005):--Setup
DECLARE @T TABLE (c1 CHAR(1), c2 CHAR(1), c3 CHAR(1))
INSERT @T
SELECT 'x', 'y', '0'
UNION ALL SELECT 'x', 'c', 'y'
UNION ALL SELECT 'x', 'n', 'c'
UNION ALL SELECT 'x', 'a', 'b'
UNION ALL SELECT 'x', 'b', 'n'
;
-- Declare...