案例表达式 SQL Server 中的 SUM

Question

我正在处理这个查询：

SELECT
       [D_INV_DATE_ID]
      ,[INVOICE_NO]
      ,[CUSTOMER_ID]
      ,[DOCUMENT_STATUS]
      ,[Total_Charge]
      ,[OPEN_CHARGE]
      ,[DSS_UPDATE_TIME]
      ,Case 
         when Total_Charge < 20 then 'less than 20'
         when Total_Charge > 20 and Total_Charge <= 50 then '20-50'
         when Total_Charge > 50 and Total_Charge <= 100 then '50-100'
         when Total_Charge > 100 then '100+'
      End as SortedBySum
  FROM [TEST].[angel].[inv3]

我需要按组对所有 when 语句进行求和，因此第一个语句必须是所有小于 20 的总和才能相加。

Answer 1

如果我猜对了，我认为以下逻辑会有所帮助-

SELECT 
[D_INV_DATE_ID],[INVOICE_NO],[CUSTOMER_ID],[DOCUMENT_STATUS],[Total_Charge],
[OPEN_CHARGE],[DSS_UPDATE_TIME],
SUM(CASE WHEN Total_Charge <= 20 THEN Total_Charge ELSE 0 END) [sum_below_equal_20],
SUM(CASE WHEN Total_Charge > 20 and Total_Charge <= 50 THEN Total_Charge ELSE 0 END) [sum_above_20_below_50],
SUM(CASE WHEN Total_Charge > 50 and Total_Charge <= 100 THEN Total_Charge ELSE 0 END) [sum_above_50_below_100],
SUM(CASE WHEN Total_Charge > 100 THEN Total_Charge ELSE 0 END) [sum_100_above]
FROM [TEST].[angel].[inv3]
GROUP BY
[D_INV_DATE_ID],[INVOICE_NO],[CUSTOMER_ID],[DOCUMENT_STATUS],[Total_Charge],
[OPEN_CHARGE],[DSS_UPDATE_TIME]