select Message,EventTime from PT_ChildSysAlarms as a
where EventTime = (select max(b.EventTime)
from PT_ChildSysAlarms as b
where a.PtName = b.PtName ) group by Message,EventTime order by EventTime desc
txl401 2017-10-18 11:02 原文
select Message,EventTime from PT_ChildSysAlarms as a
where EventTime = (select max(b.EventTime)
from PT_ChildSysAlarms as b
where a.PtName = b.PtName ) group by Message,EventTime order by EventTime desc