MySQL中重复数据清理(清理主键Id较小的)

DELETE FROM user WHERE id IN (SELECT min(id) id FROM (SELECT 
  * 
FROM 
  user 
WHERE 
  `member_id` IN (
    SELECT 
      member_id 
    FROM 
      (
        SELECT 
          member_id, 
          count(1) cnt 
        FROM 
          user 
        GROUP BY 
          member_id 
        HAVING 
          cnt > 1
      ) c
  ) )a GROUP BY `member_id`) LIMIT 49;