LINQ與子選擇查詢使用sum和group by？

Question

任何人都可以幫我一個LINQ查詢。我已經轉換的大部分，但我必須在存儲過程中的子查詢，我無法弄清楚如何做到這一點..

基本上這是舊的存儲過程（截斷爲便於）

SELECT M.Period AS 'Period' , 
      C.Code AS 'Group' , 
      C.ClientCode AS 'Code' , 
      C.ClientName AS 'Name' , 
      (SELECT SUM(Amount) AS Expr1 
       FROM  M 
       WHERE  (ClientCode = C.ClientCode) 
       GROUP BY ClientCode 
      ) AS 'Amount' , 

你可以從子查詢上面看到的是，像這樣

   SELECT SUM(Amount) AS Expr1 
       FROM  M 
       WHERE  (ClientCode = C.ClientCode) 
       GROUP BY ClientCode 
      ) AS 'Amount' 

所以我已經做了我所有的連接和我有這個迄今爲止，它的工作原理。

var test = from c in C join h in H on c.Code 
      equals h.Code join m in M on c.ClientCode 
      equals m.ClientCode 
      select new 
      { 
       Period=m.Period, 
       Group=c.Code, 
       Code= c.ClientCode, 
       Name= c.ClientName, 
       <-- Here is where i need the sub select query above --> 
      }; 

但我在如何做子查詢的損失。您可以在舊的存儲過程中看到該列的名稱爲金額。

我將不勝感激任何意見或幫助

感謝

Answer 1

林不知道在您的SQL查詢的這最後一部分，但我假設是這樣的

SELECT M.Period AS 'Period' , 
C.Code AS 'Group' , 
C.ClientCode AS 'Code' , 
C.ClientName AS 'Name' , 
(SELECT SUM(Amount) AS Expr1 
    FROM  M 
    WHERE  (ClientCode = C.ClientCode) 
    GROUP BY ClientCode 
) AS 'Amount' 
from C inner join M on C.ClientCode = M.ClientCode 

所以你的LINQ會這

var test = from c in db.C 
select new { 
    Period = c.M.Period, 
    Group = c.Code, 
    Code = c.ClientCode, 
    Name = c.ClientName, 
    Amount = (System.Int32) 
    ((from m0 in db.M 
    where 
     m0.ClientCode == c.ClientCode 
    group m0 by new { 
     m0.ClientCode 
    } into g 
    select new { 
     Expr1 = (System.Int32)g.Sum(p => p.Amount) 
    }).First().Expr1) 
}