聚合函数或 GROUP BY 子句

Posted 2023-05-08

【中文标题】聚合函数或 GROUP BY 子句

【英文标题】：An aggregate function or the GROUP BY clause

【发布时间】：2020-01-20 06:34:33

【问题描述】：

我使用了以下查询：

SELECT DISTINCT 
    b.strCostCentreID, b.strPOSOnlineRefNo, b.strPayTypeCode,
    tblMachine.strDesc AS KioskName,
    (SUM(b.dblPaidAmt)) AS RM,
    (SUM(b.dblIpay88Amt)) AS pay88AmtRM,
    (SELECT STUFF((select   ','  + strProdType
     FROM tblCurrTrx AS a
     WHERE a.strPOSOnlineRefNo = b.strPOSOnlineRefNo FOR XML PATH('')), 1, 1,'')) AS Agency
FROM 
    tblCurrTrx AS b
INNER JOIN 
    tblMachine ON b.strMachID = tblMachine.strMachID
WHERE 
    b.strPaymentMethod = '2' 
    AND (dtmTrans >= '1/3/2020') 
    AND (strTransStatus = '01')
GROUP BY 
    b.strPOSOnlineRefNo

但我收到以下错误：

消息 8120，第 16 级，状态 1，第 1 行 列 'tblCurrTrx.strCostCentreID' 在选择列表中无效，因为它既不包含在聚合函数中，也不包含在 GROUP BY 子句中。

【问题讨论】：

GROUP BY b.strCostCentreID , b.strPOSOnlineRefNo, b.strPayTypeCode, tblMachine.strDesc.

非常感谢 Akina 第一次工作。现在来了解这一点！

【参考方案1】：

请按字段添加分组

    select distinct b.strCostCentreID ,  b.strPOSOnlineRefNo, b.strPayTypeCode, tblMachine.strDesc as KioskName, 
         (SUM(b.dblPaidAmt)) as RM ,(SUM(b.dblIpay88Amt)) As pay88AmtRM ,

        (Select STUFF((select   ','  +strProdType from tblCurrTrx as a  where a.strPOSOnlineRefNo = b.strPOSOnlineRefNo for xml path('')),1,1,'')) as Agency


        From tblCurrTrx as b INNER JOIN tblMachine ON b.strMachID = tblMachine.strMachID WHERE  

        b.strPaymentMethod = '2' and (dtmTrans>='1/3/2020') AND (strTransStatus='01') 

group by b.strCostCentreID,b.strPOSOnlineRefNo, b.strPayTypeCode, tblMachine.strDesc

【参考方案2】：

试试这个：

SELECT DISTINCT b.strCostCentreID
               ,b.strPOSOnlineRefNo
               ,b.strPayTypeCode
               ,tblMachine.strDesc AS KioskName
               ,SUM(b.dblPaidAmt) AS RM
               ,SUM(b.dblIpay88Amt) AS pay88AmtRM
              ,DS.Agency
FROM tblCurrTrx AS b
INNER JOIN tblMachine 
    ON b.strMachID = tblMachine.strMachID
OUTER APPLY
(
    SELECT STUFF
    (
        (
            select   ','  + strProdType
            FROM tblCurrTrx AS a
            WHERE a.strPOSOnlineRefNo = b.strPOSOnlineRefNo 
            FOR XML PATH(''), TYPE
        ).value('.', 'NVARCHAR(MAX)')
        ,1
        ,1
        ,''
    )
) DS(Agency)
WHERE b.strPaymentMethod = '2' 
    AND dtmTrans >= '1/3/2020' 
    AND strTransStatus = '01'
GROUP BY b.strCostCentreID
        ,b.strPOSOnlineRefNo
        ,b.strPayTypeCode
        ,tblMachine.strDesc
        ,DS.Agency

【参考方案3】：

如果您使用 group by 子句而不是 select 语句列应包含在 group by 中，即

select distinct b.strCostCentreID ,  b.strPOSOnlineRefNo, b.strPayTypeCode, tblMachine.strDesc as KioskName, 
 (SUM(b.dblPaidAmt)) as RM ,(SUM(b.dblIpay88Amt)) As pay88AmtRM ,

(Select STUFF((select   ','  +strProdType from tblCurrTrx as a  where a.strPOSOnlineRefNo = b.strPOSOnlineRefNo for xml path('')),1,1,'')) as Agency


From tblCurrTrx as b INNER JOIN tblMachine ON b.strMachID = tblMachine.strMachID WHERE  

b.strPaymentMethod = '2' and (dtmTrans>='1/3/2020') AND (strTransStatus='01') group by b.strPOSOnlineRefNo, b.strCostCentreID , b.strPayTypeCode, tblMachine.strDesc 

【讨论】：

在 GROUP BY 中两次提及 b.strPOSOnlineRefNo 是多余的。