複数の列の合計値を計算する方法は？

Question

私は以下を参照してください、私はすでに私のクエリで算出された3つの新しい列から新しい「合計」欄を計算するために訓練しています：

SELECT TOP 500 request_key 
     ,request_id 
     ,CreatedTime 
     ,AssignTime 
     ,IssueTime 
     ,CloseTime 
     ,RequestDetails 
     ,request_type 
     ,Product 
     ,SiteName 
     ,DATEDIFF(MINUTE, createdtime, AssignTime + 1) AS Idle 
     ,DATEDIFF(MINUTE, AssignTime, IssueTime + 1) AS Assign 
     ,DATEDIFF(MINUTE, IssueTime, CloseTime +1) AS Delegate 

FROM [wombat].[dbo].[VwWombatCrossSiteCorrelationReport] 

新しい「合計」欄には、次のデータが必要です：アイドル+を不潔...だけでなく、+委任は

Answer 1

(DATEDIFF(MINUTE, createdtime, AssignTime + 1) AS Idle 
     + DATEDIFF(MINUTE, AssignTime, IssueTime + 1) AS Assign 
     + DATEDIFF(MINUTE, IssueTime, CloseTime +1) AS Delegate) AS total 

Answer 2

あなたは、もちろん、ただIdle、AssignとDelegateを生産し、計算を繰り返すことができ割り当て、しかし。別の計算列

SELECT *, Idle + Assign + Delegate AS Total 
FROM (SELECT TOP 500 request_key, 
         request_id, 
         CreatedTime, 
         AssignTime, 
         IssueTime, 
         CloseTime, 
         RequestDetails, 
         request_type, 
         Product, 
         SiteName, 
         DATEDIFF(MINUTE, createdtime, AssignTime + 1) AS Idle, 
         DATEDIFF(MINUTE, AssignTime, IssueTime + 1) AS Assign, 
         DATEDIFF(MINUTE, IssueTime, CloseTime +1) AS Delegate 
     FROM [wombat].[dbo].[VwWombatCrossSiteCorrelationReport]) t 

Answer 3

私はちょうどそれがシンプルになるだろうし、追加します：

SELECT TOP 500 request_key 
     ,request_id 
     ,CreatedTime 
     ,AssignTime 
     ,IssueTime 
     ,CloseTime 
     ,RequestDetails 
     ,request_type 
     ,Product 
     ,SiteName 
     ,DATEDIFF(MINUTE, createdtime, AssignTime + 1) AS Idle 
     ,DATEDIFF(MINUTE, AssignTime, IssueTime + 1) AS Assign 
     ,DATEDIFF(MINUTE, IssueTime, CloseTime +1) AS Delegate 
    , Total = DATEDIFF(MINUTE, createdtime, AssignTime + 1) + DATEDIFF(MINUTE, AssignTime, IssueTime + 1) + DATEDIFF(MINUTE, IssueTime, CloseTime +1) 
FROM [wombat].[dbo].[VwWombatCrossSiteCorrelationReport] 

Answer 4

これを行うための興味深い方法を別のオプションは、計算を繰り返すことを避けるために、サブクエリとしてこのクエリを使用することですouter applyを使用しています。

SELECT TOP 500 cr.*, v.idle, v.assign, v.delegate, 
     (v.idle + v.assign + v.delegate) as Total 
FROM [wombat].[dbo].[VwWombatCrossSiteCorrelationReport] cr outer apply 
    (select DATEDIFF(MINUTE, createdtime, AssignTime + 1) as Idle, 
      DATEDIFF(MINUTE, AssignTime, IssueTime + 1) as Assign, 
      DATEDIFF(MINUTE, IssueTime, CloseTime +1) as Delegate 
    ) v;