如何将max（number）条件放入SQL Server 2008中的where子句

Question

我的查询是：

Select 
    res.*, s.Description as GroupSpecialty, 
    MAX(CASE WHEN Period = @Q9 THEN cases END) OVER (PARTITION BY Group,Zone) as CompletedVolume 
from 
    res

我需要做的是消除CompletedVolume <50时的所有数据。

当我where CompletedVolume >= 50写时，它说没有列作为CompletedVolume 。 当我写MAX(CASE WHEN Period = @Q9 THEN cases END) OVER (PARTITION BY Group, Zone) >= 50 ，它说

窗口函数只能出现在SELECT或ORDER BY子句中

因此，我无法提供此条件。 我怎样才能做到这一点？ 谢谢。

Answer 1

使用查询作为派生表

SELECT *
FROM 
  (select res.*, s.Description as GroupSpecialty, 
  MAX(CASE WHEN Period=@Q9 THEN cases END) OVER (PARTITION BY Group,Zone) as CompletedVolume 
  from res) DerivedTable
WHERE CompletedVolume < 50

或CTE

;WITH cte
AS
(
select res.*, s.Description as GroupSpecialty, 
MAX(CASE WHEN Period=@Q9 THEN cases END) OVER (PARTITION BY Group,Zone) as CompletedVolume 
from res
)

SELECT * from cte
where completedvolume < 50