如何修复 Group By 中的聚合，缺少聚合值

Question

我有 table 的销售信息，我对按客户分组并返回几列的总和、计数、最大值感兴趣。有什么想法请。

我检查了所有 Select 列都包含在 Group By 语句中，返回的是详细信息而不是分组和聚合值。
我尝试了一些明确的命名，但没有帮助。

SELECT
    customerID AS CUST,
    COUNT([InvoiceID]) AS Count_Invoice,
    SUM([Income]) AS Total_Income,
    SUM([inc2015]) AS Tot_2015_Income,
    SUM([inc2016]) AS Tot_2016_Income,
    MAX([prodA]) AS prod_A,
FROM [table_a] 
GROUP BY
    customerID, InvoiceID,Income,inc2015, inc2016, prodA

有多行 CUST，即 CUST 1、2 等应该有一行....它应该这样说...

    ---------------------------------------------
    CUST    Count_Invoice   Total_Income    Tot_2015_Income Tot_2016_Income prod_A

       1    2   600 300 300 2


    BUT IT IS RETURNING THIS
    ======================================
    CUST    Count_Invoice   Total_Income    Tot_2015_Income Tot_2016_Income prod_A

       1    1   300 300 0   1

       1    1   300 0   300 1

       2    1   300 0   300 1

       2    1   500 0   500 0

       3    2   800 0   800 0

       3    1   300 0   300 1

Answer 1

根据您对预期输出的描述，您应该仅按客户汇总：

SELECT
    customerID A CUST,
    COUNT([InvoiceID]) AS Count_Invoice,
    SUM([Income]) AS Total_Income,
    SUM([inc2015]) AS Tot_2015_Income,
    SUM([inc2016]) AS Tot_2016_Income,
    MAX([prodA]) AS prod_A
FROM [table_a] 
GROUP BY  
    customerID;

Answer 2

您不需要 group by 其他列，因为它们已经按 count、min、max 或 sum 聚合。

所以你可以试试这个

SELECT customerID as CUST
,count([InvoiceID]) as Count_Invoice
 ,sum([Income]) as Total_Income
,sum([inc2015]) as Tot_2015_Income
 ,sum([inc2016]) as Tot_2016_Income
,max([prodA])  as prod_A    --- here you are taking Max but in output it seems like sum
 FROM [table_a] 
 Group By customerID

注意：对于 prod_A 列，您使用的 max 给出 1 但结果显示 2 实际上是 sum 或 count。请检查。

有关详细信息，您可以找到 Group by 的 link。

如何修复 Group By 中的聚合，缺少聚合值

How to fix Aggregation in Group By, missing aggregation values

sql-server

grouping

group-by

aggregation