如果回路“然后” Case语句的语句在SQL Server 2008中

Question

如果我想用如果条件然后声明案例语句在SQL Server 2008中如何使用它？

Answer 1

您可以使用关键字Then声明Case在SQL Server

SELECT ProductNumber, Category = 
     CASE ProductLine 
     WHEN TestRowValue = 'R' THEN 
       Case When TestColumn = 'P' THEN 'Road' 
       ELSE 'Board' 
     WHEN 'M' THEN 'Mountain' 
     WHEN 'T' THEN 'Touring' 
     WHEN 'S' THEN 'Other sale items' 
     ELSE 'Not for sale' 
     END, 
    Name 
FROM Production.Product 

Answer 2

鸟巢他们

CASE 
    WHEN foo = 'bar' THEN 
       CASE 
       WHEN black = 'white' THEN .. 
       WHEN W = 'TF' THEN ... 
       ELSE 
       END 
    WHEN fish = 'bicycle' THEN ... 
    ELSE ... 
END