如何优化我的查询？

Question

我编写了这段代码，它可以查找下来的节点并计算上下小时。此代码有效，但我想知道其他方式或优化此代码？计算停机时间的最佳方法是什么？有什么方式（交互方式），用户可以输入日期和时间间隔？

 
SELECT q1.nodeid, q1.VendorIcon, q1.Caption, q1.IP_Address, 
q1.OutageDurationInMinutes, 
q2.TimeUp 

FROM 
(SELECT 
    Nodes.NodeID AS NodeID, ltrim(rtrim(Nodes.Caption)) Caption, Nodes.VendorIcon,Nodes.IP_Address, 
    sum(DATEDIFF(hh, StartTime.EventTime, EndTime.EventTime)) as OutageDurationInMinutes 

FROM Events StartTime 
Left join Events EndTime On 
    EndTime.EventType = '5' and 
    EndTime.NetObjectType = 'N' and 
    EndTime.NetworkNode = StartTime.NetworkNode and 
    EndTime.EventTime = 
        (
         Select 
          min(EventTime) 
         from Events 
         where 
          EventTime>StartTime.EventTime and 
          EventType = '5' and 
          NetObjectType = 'N' and 
          NetworkNode = StartTime.NetworkNode 
        )  
INNER JOIN Nodes ON 
    StartTime.NetworkNode = Nodes.NodeID 
WHERE 
    Nodes.Department = '4' AND 
    StartTime.EventType = 1 AND 
    StartTime.NetObjectType = 'N' AND 
    StartTime.eventtime between dateadd(M, -1, getdate()) and getdate() 

Group by 
    Nodes.NodeID,Nodes.Caption, Nodes.VendorIcon,Nodes.IP_Address, Nodes.LastBoot 
) q1 

INNER JOIN 

(SELECT 
     Nodes.NodeID AS NodeID 
     ,ltrim(rtrim(Caption)) Caption 
     ,VendorIcon 
     ,Ip_Address 
     ,DateDiff(hour,Nodes.LastBoot,GetDate()) AS HoursUp 
     ,CONVERT(VARCHAR(40), DATEDIFF(minute, Nodes.LastBoot, GETDATE())/(24*60)) 
      + ' days, ' 
      + CONVERT(VARCHAR(40), DATEDIFF(minute, Nodes.LastBoot, GETDATE())%(24*60)/60) 
    + ' hours, and ' 
    + CONVERT(VARCHAR(40), DATEDIFF(minute, Nodes.LastBoot, GETDATE())%60) 
    + ' minutes.' AS TimeUp 
FROM [Nodes] 
Where 

LastBoot between dateadd(day, -30, getdate()) and getdate()) q2 on q1.NodeID=q2.NodeID 

Order by Caption 

Answer 1

我想知道任何其他方式或 优化此代码？

我建议查看一下查询执行计划。

有什么办法（交互方式），其 用户可以输入日期和时间 间隔？

你可以只确定值，在运行查询之前，并在查询中使用这些参数（我不知道但什么叫你的查询，它是一个存储过程？）