Question

寻找一种方法是SQL Server

表1 - Status_Latest

DeviceID Status(bit) TimeOfUpdate(datetime)

表2 - Status_History

DeviceID Status(bit) TimeOfUpdate(datetime)

寻找实现这一目标的最快方法：

调用存储过程，它传递DeviceID和状态。

如果DeviceID中不存在Status_Latest，请同时插入Status_Latest和Status_History

如果值与Status_Latest中的当前值不同，请更新它并存储到Status_History

我在想

选项A：如果值不同，我可以从Status_Latest中选择，然后更新Status_Latest和Status_History。

选项B：我可以在存储旧值时更新Status_Latest吗？如果值不同，请更新Status_Latest和Status_History

到目前为止我所拥有的内容（仅在应用程序中调用，需要在DB存储过程中处理）

insert into [SensorStateChange_History] (SensorIndex, SensorOccupied, TimeOfDataBaseStorage)
values (@SensorIndex, @SensorOccupied, GETUTCDATE())

update SensorState_Latest
set SensorOccupied = @SensorOccupied, 
    TimeOfDataBaseStorage = GETUTCDATE()
and SensorIndex = @SensorIndex

if @@ROWCOUNT = 0

insert into SensorState_Latest
values (@SensorIndex, @SensorOccupied, GETUTCDATE())

Answer 1

我将如何做到这一点：

IF NOT EXISTS(SELECT * FROM [SensorStateChange_Latest] WHERE SensorIndex=@SensorIndex AND SensorOccupied=@SensorOccupied)
  BEGIN
  update SensorState_Latest
  set SensorOccupied = @SensorOccupied, 
    TimeOfDataBaseStorage = GETUTCDATE()
  WHERE SensorIndex = @SensorIndex;    

  if @@ROWCOUNT = 0    
    insert into SensorState_Latest
    values (@SensorIndex, @SensorOccupied, GETUTCDATE())

  insert into [SensorStateChange_History] (SensorIndex, SensorOccupied, TimeOfDataBaseStorage)
  values (@SensorIndex, @SensorOccupied, GETUTCDATE());

  END

用于存储最新值和历史记录表的SQL Server存储过程

1 个答案: