如何根据where条件对行求和

Question

我有以下格式的数据集存储在excel中。

我写错了下面的结果。

查询应返回一行。如果输入其他计算列，也会发生同样的情况。因此，如果我同样添加数量2，数量3，则行数增加4（每个数量为2），总计为6行，其中3行将返回NULL值。

表结构，示例数据和我的查询如下：

https://dbfiddle.uk/?rdbms=sqlserver_2017&fiddle=3f8c9931554863583616d0f662230996

Answer 1

您可以使用过滤器

having sum(sales) is not null

在小提琴之后编辑

select CustomerName,BillNo,  sum(Amount)
from [dbo].[MarginTemp]
where [Type] = 'A'
group by  customername,BillNo

修改您今天的

SELECT  
       MAT.BillNo,MAT.ServiceCategoryName, 
       'Sep-19' AS MonthName,
    SUM(case when MAT.ServiceCategoryName = 'Z-Net Revenue'
     then MAT.Amount else 0 end) AS Amount

FROM MarginTemp MAT

WHERE 
MAT.BillNo='A202019339291'
GROUP BY MAT.BillNo,
         MAT.ServiceCategoryName
         having SUM(case when MAT.ServiceCategoryName = 'Z-Net Revenue'
     then MAT.Amount else 0 end)>0
ORDER BY BillNo ASC;

您的查询中的值为空，因为您在分组中仅使用了一个MAT.BillNo,MAT.ServiceCategoryName，其中只有一个ServiceCategoryName满足条件，对于其他条件则显示为空

经过讨论，我得到了原始的问题

with cte as
(SELECT MAT.BillNo,
       ---MAT.ServiceCategoryName, 
       'Sep-19' AS MonthName
       ,  SUM( case when MAT.ServiceCategoryName='Z-NET Revenue' then MAT.Amount else 0 end) as AMOUNT
      , SUM( case when MAT.ServiceCategoryName='Internal Dr Visit Charges' then MAT.Amount else 0 end) as [Internal Dr Visit Charges]
      ,SUM( case when MAT.ServiceCategoryName='External Dr Visit Charges' then MAT.Amount else 0 end) as [External Dr Visit Charges]

FROM MarginTemp MAT
WHERE MAT.BillNo = 'A202019339291'

GROUP BY MAT.BillNo, 
         MAT.ServiceCategoryName
) select BillNo,MonthName,max(AMOUNT) as amt,
max([Internal Dr Visit Charges]) as [Internal Dr Visit Charges]
,max([External Dr Visit Charges]) as [External Dr Visit Charges]
from cte
group by BillNo,MonthName

Answer 2

您的查询看起来像这样吗？

select customerid, customername, sum(sales)
from t
where subtype = 'A'
group by customerid, customername;

每个customerid / customername组合仅返回一行，而不返回多行。