delimiter $$ CREATE PROCEDURE swap(INOUT a int, INOUT b int) BEGIN SET @tmp = a; SET a = b; SET b = @tmp; END $$ delimiter ; #호출방법 SET @a = 3, @b = 7; select @a, @b #a = 3, b = 7 call swap(@a, @b); select @a, @b #b = 3, a = 7