where子句中的SQL Case语句指定条件？

Question

我有以下查询：

SELECT * 
FROM dbo.tblOrders o 
WHERE o.OrderId IN (SELECT [Value] FROM [dbo].[udf_GenerateVarcharTableFromStringList](@OrderId, ',')) 
AND 
@ActiveInactive = 
CASE 
WHEN 'Active' THEN (o.[orderactivedate] > o.[orderinactivedate]) 
WHEN 'Inactive' THEN (o.[orderactivedate] < o.[orderinactivedate]) 
END 

这将返回

An expression of non-boolean type specified in a context where a condition is expected, near 'THEN'. 

我将如何得到这个工作？说如果该参数是'活动'，然后按照以下标准返回记录？

Answer 1

你可以做的另一种方法：

SELECT * 
FROM dbo.tblOrders o 
WHERE o.OrderId IN (SELECT [Value] FROM [dbo].[udf_GenerateVarcharTableFromStringList](@OrderId, ',')) 
AND ((@ActiveInactive = 'Active' AND o.[orderactivedate] > o.[orderinactivedate]) 
OR (@ActiveInactive = 'Inactive' AND o.[orderactivedate] < o.[orderinactivedate])) 

Answer 2

你为什么不添加OR条件？像

SELECT... WHERE ... 
AND ((@ActiveInactive = 'Active' AND o.[orderactivedate] > o.[orderinactivedate]) OR 
    (@ActiveInactive = 'Inactive' AND o.[orderactivedate] < o.[orderinactivedate])) 

Answer 3

你不能有一个比较表达式在这样的

一个情况下，我会考虑这个选项，比较更改为正常表达

... 
AND 
CASE @ActiveInactive 
WHEN 'Active' THEN DATEDIFF(day, o.[orderinactivedate], o.[orderactivedate]) 
WHEN 'Inactive' THEN DATEDIFF(day, o.[orderactivedate], o.[orderinactivedate]) 
END > 0 

或者这一点，您可以在SIGN()表达有一个计算列

SIGN(DATEDIFF(day, o.[orderinactivedate], o.[orderactivedate])) = 
       CASE WHEN @ActiveInactive WHEN 'Active' THEN 1 WHEN 'InActive' THEN -1 END 

Answer 4

SELECT * 
FROM dbo.tblOrders o 
WHERE o.OrderId IN (SELECT [Value] FROM [dbo].[udf_GenerateVarcharTableFromStringList](@OrderId, ',')) 
AND 
@ActiveInactive = 
CASE 
WHEN (o.[orderactivedate] > o.[orderinactivedate]) then 'Active' 
WHEN (o.[orderactivedate] < o.[orderinactivedate]) THEN 'Inactive' 
END