是否可以在select/group by语句中使用if子句？还是另一种解决方案

Question

使用SQLServer的2008

目前，我有如下图所示（虽然有在我刚刚填写他们在这里给什么样的投入可能是一个更好的主意函数变量）实现的功能的功能。

我想知道是否有一种方法，当你定义为如果你没有通过的条款选择/组中定义它@id为空值（目前在合并上v.ID使用）来匹配一切吗？

 SELECT 
      'ALL' as GeogType, 
      CAST(v.AdmissionOn as date) as dtAdmission, 
      (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) as timeInterval, 
      CAST((DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1) as nvarchar) + ':00' as fromTime, 
      CAST((DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1) + (24/1) as nvarchar) + ':00' as toTime,  
      v.ID, 
      COUNT(*) as nVisits 
     FROM dbo.Table1 v INNER JOIN dbo.Table2 t ON v.FSLDU = t.FSLDU5 
     WHERE v.AdmissionOn >= '01-01-2010' AND v.AdmissionOn < DATEADD(day,1,'02-01-2010') 
       AND v.ID = Coalesce(@id,ID) 
     GROUP BY  
      CAST(v.AdmissionOn as date), 
      (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1), 
      (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1), 
      (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1) + (24/1), 
      v.ID  
     ORDER BY 2,3,4 

它将返回设置类似这样的结果，当@id为空：

ALL 2010-01-01 0 0:00 24:00 7 4 
ALL 2010-01-01 0 0:00 24:00 4 54 
ALL 2010-01-01 0 0:00 24:00 0 2303 
ALL 2010-01-01 0 0:00 24:00 3 412 
ALL 2010-01-01 0 0:00 24:00 6 57 
ALL 2010-01-01 0 0:00 24:00 2 64 
ALL 2010-01-01 0 0:00 24:00 5 5 
ALL 2010-01-01 0 0:00 24:00 1 103 

但我想它改为：

ALL 2010-01-01 0 0:00 24:00 ? 3002 

我不知道是什么会去？列，可能类似于1,2,3,4,5,6,7？

这是否可以通过诸如select/group by子句或我不知道的存储过程之类的事情来完成？如果没有，我可以创建一个新的函数，但我希望只需输入@id为空即可。

Answer 1

更改组通过为：

GROUP BY CAST(v.AdmissionOn as date), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1) + (24/1), 
    Case @Id When Null Then 0 Else Id End 

果然不出我所编辑的这，但不会单独工作是：

GROUP BY CAST(v.AdmissionOn as date), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1) + (24/1), 
    @Id 

- 无论这些本身会导致一个错误，因为中的select语句不在Group By中。这两者都可以通过与集团选择相一致correctted通过

SELECT 'ALL' as GeogType, CAST(v.AdmissionOn as date) as dtAdmission, 
     (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) as timeInterval, 
     CAST((DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * 
       (24/1) as nvarchar) + ':00' as fromTime, 
     CAST((DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * 
       (24/1) + (24/1) as nvarchar) + ':00' as toTime, 
     Case @Id When Null Then 0 Else Id End Id, 
     COUNT(*) as nVisits 
    FROM dbo.Table1 v 
     JOIN dbo.Table2 t 
      ON v.FSLDU = t.FSLDU5 
    WHERE v.AdmissionOn >= '01-01-2010' 
     AND v.AdmissionOn < DATEADD(day,1,'02-01-2010') 
     AND v.ID = Coalesce(@id,ID)  
    GROUP BY CAST(v.AdmissionOn as date), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1) + (24/1), 
    Case @Id When Null Then 0 Else Id End 

或

SELECT 'ALL' as GeogType, CAST(v.AdmissionOn as date) as dtAdmission, 
     (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) as timeInterval, 
     CAST((DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * 
       (24/1) as nvarchar) + ':00' as fromTime, 
     CAST((DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * 
       (24/1) + (24/1) as nvarchar) + ':00' as toTime, 
     @Id Id, COUNT(*) as nVisits 
    FROM dbo.Table1 v 
     JOIN dbo.Table2 t 
      ON v.FSLDU = t.FSLDU5 
    WHERE v.AdmissionOn >= '01-01-2010' 
     AND v.AdmissionOn < DATEADD(day,1,'02-01-2010') 
     AND v.ID = Coalesce(@id,ID)  
    GROUP BY CAST(v.AdmissionOn as date), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1), 
    (DATEPART(hour,CAST(AdmissionOn as time)))/(24/1) * (24/1) + (24/1), 
    @Id 

Answer 2

GROUP BY @id，而不是GROUP BY v.id，并且在SELECT语句替换v.id与@id。