select 후 Update 예제

UPDATE                                          
       (SELECT a1 as aaa
             , (SELECT b1
                  FROM  T2
                 WHERE T2.b1 = T1.a1 ) as bbb
          FROM T1
         WHERE T1.a3  = '1'
        ) I1
  SET aaa = bbb
WHERE aaa <> bbb

 

여기가 더 잘되어 있네 +.+   http://www.songtory.com/post/001004/1/136