Find the greatest common factor of two positive integers.
CREATE FUNCTION gcd(x int, y int) RETURNS int DETERMINISTIC BEGIN DECLARE dividend int; DECLARE divisor int; DECLARE remainder int; SET dividend := GREATEST(x, y); SET remainder := LEAST(x, y); WHILE remainder != 0 DO SET divisor = remainder; SET remainder = MOD(dividend, divisor); SET dividend = divisor; END WHILE; RETURN divisor; END