您需要使用一个子查询，该子查询为每个RefId提取最新的Entered值，然后将您的源表与此RefId上的Entered联接起来：
SELECt DISTINCT MyTable.LogId, MyTable.Entered FROM MyTableINNER JOIN (SELECt RefId, MAX(Entered) as Entered FROM MyTable GROUP BY RefId) LatestON MyTable.RefId = Latest.RefId AND MyTable.Entered = Latest.Entered
