参考例子
http://sqlfiddle.com/#!6/a63a6/457
SELECT LogicalStationID,[气体浓度_DLastValue],[传感器状态_DLastValue], [水位状态_DLastValue],[电池状态_DLastValue], case when [气体浓度_DLastTime]>=[传感器状态_DLastTime] and [气体浓度_DLastTime]>=[水位状态_DLastTime] and [气体浓度_DLastTime]>=[电池状态_DLastTime] Then convert(datetime,[气体浓度_DLastTime]) when [传感器状态_DLastTime]>=[气体浓度_DLastTime] and [传感器状态_DLastTime]>=[水位状态_DLastTime] and [传感器状态_DLastTime]>=[电池状态_DLastTime] Then convert(datetime,[传感器状态_DLastTime]) when [水位状态_DLastTime]>=[气体浓度_DLastTime] and [水位状态_DLastTime]>=[传感器状态_DLastTime] and [水位状态_DLastTime]>=[气体浓度_DLastTime] Then convert(datetime,[水位状态_DLastTime]) when [电池状态_DLastTime]>=[传感器状态_DLastTime] and [电池状态_DLastTime]>=[气体浓度_DLastTime] and [电池状态_DLastTime]>=[水位状态_DLastTime] Then convert(datetime,[电池状态_DLastTime]) end as [DLastTime] FROM ( SELECT LogicalStationID, col, val FROM( SELECT *, Name+'_DLastValue' as Col, DLastValue as Val FROM [zhouweiTest].[dbo].[SensorReal] UNION SELECT *, Name+'_DLastTime' as Col,CONVERT(float, DLastTime) as Val FROM [zhouweiTest].[dbo].[SensorReal] ) t ) tt PIVOT ( max(Val) for Col in ([气体浓度_DLastValue],[气体浓度_DLastTime],[传感器状态_DLastValue],[传感器状态_DLastTime], [水位状态_DLastValue],[水位状态_DLastTime],[电池状态_DLastValue],[电池状态_DLastTime]) ) AS pvt
