sql将行与条件组合在一个表中并选择最大修订版本

Question

我有一个查询组合行如下：

UPDATE  SO_DistributionList
SET [Distribution_List_Item]=REPLACE([Distribution_List_Item],' ','|')
SELECT mainID as 'MainID',Revision,reqno as 'Request No',REPLACE
(Units,'|', ' ')  as 'Distribution list item' FROM
(SELECT t1.mainid, t1.revision,t1.reqno,
   Units =REPLACE( 
   (SELECT Distribution_List_Item AS [data()]
       FROM SO_DistributionList] t2
      WHERE t2.mainid = t1.mainid and t2.revision = t1.revision
      ORDER BY Distribution_List_Item
        FOR XML PATH('')
        ), ' ', ';')
  FROM SO_DistributionList t1
  GROUP BY mainID, Revision,reqno)
  t0

以上查询的结果：

但是，我想选择要显示的最大版本而不是全部。

谢谢。