删除相同的记录
找出相同的记录
select * from file_hanjian_info a where rowid !=(select  max(rowid) 
    from file_hanjian_info b where a.docid=b.docid)

删除
delete  from file_hanjian_info a where rowid !=(select  max(rowid) 
    from file_hanjian_info b where a.docid=b.docid)