SELECT g.no, g.name, r.no, r.num, r.name FROM guest g, guest_reply r where g.no<>r.num order by g.no desc

SELECT g.*, r.no, r.num FROM guest g INNER JOIN  guest_reply r ON g.no=r.num order by g.no desc

SELECT g.*, r.no, r.num FROM guest g INNER JOIN  guest_reply r ON g.no=r.num=NULL order by g.no desc