SELECT  top 1 wb_bbsReply.replyTime, wb_bbsReply.postId, wb_bbsPost.postTitle
FROM wb_bbsReply INNER JOIN
  wb_bbsPost ON wb_bbsReply.postId = wb_bbsPost.postId
  where wb_bbsReply.userId=@userid
order by wb_bbsReply.replyTime desc

------解决方案--------------------
SQL code
SELECT min(wb_bbsReply.replyTime), min(wb_bbsReply.postId), wb_bbsPost.postTitle
FROM wb_bbsReply INNER JOIN
  wb_bbsPost ON wb_bbsReply.postId = wb_bbsPost.postId
  where wb_bbsReply.userId=@userid
group by  wb_bbsPost.postTitle

------解决方案--------------------

wb_bbsReply 是一个贴子回复表？
wb_bbsPost 是BBS的贴子列表？

如果是就可以这样试试
SQL code

Select wb_bbsPost.postTitle,
replyTime=(select top 1 replyTime From wb_bbsReply Where wb_bbsReply.postId = wb_bbsPost.postId Order By wb_bbsReply.repluTime Desc ),
wb_bbsPost.postId
From wb_bbsPost
Where exists (Select * From wb_bbsReply 
Where wb_bbsReply.postId = wb_bbsPost.postId
and wb_bbsReply.userId=@userid
   )