SQL在WHERE IN子句中使用CASE语句

Question

在where子句中使用case是否可行？像这样的东西:

 DECLARE @Status VARCHAR(50);
 SET @Status='published';

 SELECT * FROM Product P    
 WHERE P.Status IN (CASE WHEN @Status='published' THEN (1,3)
                                   WHEN @Status='standby' THEN (2,5,9,6)
                                   WHEN @Status='deleted' THEN (4,5,8,10)
                                   ELSE (1,3)
                                   END)

此代码提供错误:','附近的语法不正确.

Answer 1

不,你不能使用case和in喜欢这个.但你可以做到

SELECT * FROM Product P    
WHERE @Status='published' and P.Status IN (1,3)
or @Status='standby' and P.Status IN  (2,5,9,6)
or @Status='deleted' and P.Status IN (4,5,8,10)
or P.Status IN (1,3)

顺便说一句,你可以减少到

SELECT * FROM Product P    
WHERE @Status='standby' and P.Status IN (2,5,9,6)
or @Status='deleted' and P.Status IN (4,5,8,10)
or P.Status IN (1,3)

既然or P.Status IN (1,3)给你所有的记录@Status='published' and P.Status IN (1,3)

Answer 2

我意识到这已经得到了回答,但是接受的解决方案存在一些问题.它会返回误报.易于修复:

SELECT * FROM Products P    
WHERE (@Status='published' and P.Status IN (1,3))
   or (@Status='standby' and P.Status IN  (2,5,9,6))
   or (@Status='deleted' and P.Status IN (4,5,8,10))
   or (@Status not in ('published','standby','deleted') and P.Status IN (1,2))

• SQL小提琴演示

不需要括号(尽管可能更容易阅读,因此我将它们包括在内).