如何将此SQL语句转换为LINQ？

Question

我不知道如何将此SQL语句转换为使用OUTER APPLY和TOP的LINQ。有人可以提出一个想法如何处理它。谢谢！

SELECT Cust.CustomerName, Ord.OnlineOrderTitle, Pro.ProductTitle, 
Pic.PictureFilename, PCom.PictureCommentText, Ord.OnlineOrderDateAdded 
FROM Customer as Cust 
OUTER APPLY 
(SELECT * FROM OnlineOrder 
WHERE CustomerID = Cust.CustomerID) as Ord 
OUTER APPLY 
(SELECT * FROM Product 
WHERE OnlineOrderID = Ord.OnlineOrderID) as Pro 
OUTER APPLY 
(SELECT TOP 1 * FROM Accessory 
WHERE ProductID = Pro.ProductID) as Acc 
OUTER APPLY 
(SELECT TOP 1 * FROM Picture 
WHERE ProductID = Pro.ProductID) as Pic 
OUTER APPLY 
(SELECT TOP 1 * FROM PictureComment 
WHERE PictureID = Pic.PictureID) as PCom 
ORDER BY Ord.OnlineOrderDateAdded DESC 

Answer 1

LINQ不支持SQL样式外连接本机（水平除了结果集的意义上），但你可以做一个组合参加，并返回一个空组，如果加入，反而找不到很容易模仿他们结果。看看MSDN页面How to: Perform Left Outer Joins (C# Programming Guide)和How to: Combine Data with LINQ by Using Joins (Visual Basic)。