mysql sum()関数はどうして正しい結果が得られないのですか!!!

      ：     state=1       ，     state=1       。                        id，    ，    。    ：
SELECT a.userid,SUM(a.number) AS mai,SUM(i.total) AS hua
FROM account AS a,info AS i
WHERE a.state=1 AND a.userid=i.userid AND i.state=1
GROUP BY a.userid
HAVING SUM(a.number)>SUM(i.total)
      ，       。。。
    4   。  3   。
         *3 。      *4  ！！！！         ！！

      ！！！！！！


SELECT 
  a.userid,
  a.mai,
  i.hua
FROM 
  (SELECT userid, SUM(number) AS mai FROM account WHERE state=1 GROUP BY userid) AS a,
  (SELECT userid, SUM(total) AS hua FROM info  WHERE state=1  GROUP BY userid) AS i
WHERE 
  a.userid=i.userid
  AND a.mai > i.hua