SQL 优化：提高演员 '陈小龙' 出演的 '北影' 制作电影票价

UPDATE I SET price = price * 1.2 WHERE mno IN ( SELECT mno FROM R JOIN A ON R.ano = A.no JOIN M ON R.mno = M.mno JOIN C ON M.cno = C.cno WHERE A.name = '陈小龙' AND C.cname = '北影' );