在分组之前需要对联接表进行排序的联接表出现问题

select t.ThreadID, p.PostID, p.Postedfrom Thread tinner join (    select ThreadID, Max(Posted) as MaxPosted    from Post    group by ThreadID       ) pm on t. ThreadID = pm.ThreadIDinner join Post p on pm.ThreadID = p.ThreadID and pm.MaxPosted = p.Postedorder by p.Posted desc