T-SQL CASE多个条件相同的结果

Question

我在SQL需要

int caseSwitch = 1; 
switch (caseSwitch) 
{ 
case 1: 
case 2: 
case 3: 
case 4: 
    Console.WriteLine("x"); 
    break; 
default: 
    Console.WriteLine("Default case"); 
    break; 
} 

等价的C＃代码我有多个条件，相同的结果 ，我不想写的所有代码

case when cond1 then result1 
    when cond2 then result1 
    when cond3 then result1 
    .... 
    end 

有什么想法？ 感谢

Answer 1

事情是这样的：

DECLARE @caseSwitch INT=1 
SELECT 
    CASE WHEN @caseSwitch IN (1,2,3,4) 
    THEN 'x' 
    ELSE 'Default case' 
END 

在选择一个表。这将是这样的：

DECLARE @caseSwich INT=1 
SELECT 
    (
     CASE WHEN @caseSwich IN (1,2,3,4) 
      THEN 'x' 
      ELSE 'Default case' 
     END 
    ) AS someColumn 
FROM 
    yourTable 

Answer 2

DECLARE @i INT 
SET @i = 2 
SELECT CASE WHEN @i IN (1,2,3,4) THEN 'Hi' ELSE 'HiHi' END AS Result 

Answer 3

如果设定值小而稳定，然后使用CASE表达，否则就把值查找表例如

SELECT T.*, L.lookup_value AS result 
    FROM T JOIN LookupTable ON T.lookup_key = L.lookup_key 
UNION 
SELECT T.*, 'Default case' AS result 
    FROM T 
WHERE lookup_key NOT IN (SELECT lookup_key FROM LookupTable);