Sql 如何在联接查询中使用MAX（）

我想创建一个查询，从recit表中获取RECID，它是Customer表中的custname和recit上的最大RECID。但不知何故，这个查询抛出了一个错误。它始于我将maxMAXREC.REC_Id_I添加为RECID时

查询是：

SELECT
    REC.REC_Id_I,
    REC.REC_No_V,
    CUS.CUS_Name_V,
    REC.REC_PaidAmount_M,
    CASE
        WHEN REC.REC_PayMode_C = 'C' THEN 'Cash'
        ELSE 'Cheque'
    END AS REC_PayMode_C,
    REC.REC_BankName_V,
    REC.REC_BankAddress,
    REC.REC_ChequeNo_V,
    convert(varchar, REC.REC_ChequeDate_D, 103) AS REC_ChequeDate_D,
    REC.REC_Date_D,
    MAX(REC.REC_Id_I) As RECID
FROM TBL_Receipts REC
JOIN TBL_CustomerMaster CUS ON REC.REC_CustomerId_I = CUS.CUS_Id_I
WHERE
  REC_Active_c='y'
  AND REC_SalesMasterId_I='0'
ORDER BY REC_Id_I

错误是：

Msg 8120，级别16，状态1，程序sp_Receivement_Select，第15行列“TBL_Receives.REC_Id_I”在选择列表中无效，因为它不包含在聚合函数或GROUP BY子句中

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除聚合函数外，您几乎需要按所有选定的列进行分组。如果您考虑结果将如何显示，那么所有列都应位于组中，这对您来说应该是有意义的：

SELECT
    REC.REC_Id_I,
    REC.REC_No_V,
    CUS.CUS_Name_V,
    REC.REC_PaidAmount_M,
    CASE
        WHEN REC.REC_PayMode_C = 'C' THEN 'Cash'
        ELSE 'Cheque'
    END AS REC_PayMode_C,
    REC.REC_BankName_V,
    REC.REC_BankAddress,
    REC.REC_ChequeNo_V,
    convert(varchar, REC.REC_ChequeDate_D, 103) AS REC_ChequeDate_D,
    REC.REC_Date_D,
    MAX(REC.REC_Id_I) As RECID
FROM TBL_Receipts REC
JOIN TBL_CustomerMaster CUS ON REC.REC_CustomerId_I = CUS.CUS_Id_I
WHERE
  REC_Active_c='y'
  AND REC_SalesMasterId_I='0'
 GROUP BY 
    REC.REC_Id_I,
    REC.REC_No_V,
    CUS.CUS_Name_V,
    REC.REC_PaidAmount_M,
    CASE
        WHEN REC.REC_PayMode_C = 'C' THEN 'Cash'
        ELSE 'Cheque'
    END AS REC_PayMode_C,
    REC.REC_BankName_V,
    REC.REC_BankAddress,
    REC.REC_ChequeNo_V,
    convert(varchar, REC.REC_ChequeDate_D, 103) AS REC_ChequeDate_D,
    REC.REC_Date_D
ORDER BY REC_Id_I

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添加GROUPBY子句时会出现什么错误？永远不要写你有错误，总是写错误是什么

我不知道您是如何使用GROUP BY子句编写查询的，因为您尚未向我们展示它，但请尝试以下方法：

SELECT
    REC.REC_Id_I,
    REC.REC_No_V,
    CUS.CUS_Name_V,
    REC.REC_PaidAmount_M,
    CASE
        WHEN REC.REC_PayMode_C = 'C' THEN 'Cash'
        ELSE 'Cheque'
    END AS REC_PayMode_C,
    REC.REC_BankName_V,
    REC.REC_BankAddress,
    REC.REC_ChequeNo_V,
    convert(varchar, REC.REC_ChequeDate_D, 103) AS REC_ChequeDate_D,
    REC.REC_Date_D,
    MAX(REC.REC_Id_I) As RECID
FROM TBL_Receipts REC
JOIN TBL_CustomerMaster CUS ON REC.REC_CustomerId_I = CUS.CUS_Id_I
WHERE
  REC_Active_c='y'
  AND REC_SalesMasterId_I='0'
GROUP BY
  REC.REC_Id_I,
  REC.REC_No_V,
  CUS.CUS_Name_V,
  REC.REC_PaidAmount_M,
  CASE
      WHEN REC.REC_PayMode_C = 'C' THEN 'Cash'
      ELSE 'Cheque'
  END,
  REC.REC_BankName_V,
  REC.REC_BankAddress,
  REC.REC_ChequeNo_V,
  convert(varchar, REC.REC_ChequeDate_D, 103),
  REC.REC_Date_D
ORDER BY REC_Id_I;

---

如果您的GROUPBY子句仍然存在问题，您可以尝试类似的方法，即使这不是最佳解决方案，它也应该可以工作

SELECT
    REC.REC_Id_I,
    REC.REC_No_V,
    CUS.CUS_Name_V,
    REC.REC_PaidAmount_M,
    CASE
        WHEN REC.REC_PayMode_C = 'C' THEN 'Cash'
        ELSE 'Cheque'
    END AS REC_PayMode_C,
    REC.REC_BankName_V,
    REC.REC_BankAddress,
    REC.REC_ChequeNo_V,
    convert(varchar, REC.REC_ChequeDate_D, 103) AS REC_ChequeDate_D,
    REC.REC_Date_D,
    recid.maxRECID As RECID
FROM TBL_Receipts REC
JOIN TBL_CustomerMaster CUS ON REC.REC_CustomerId_I = CUS.CUS_Id_I
JOIN (SELECT MAX(REC_ID_I) as maxRECID, REC_CustomerId_I FROM REC group by REC_CustomerId_I) as recid ON recid.REC_CustomerId_I = REC.REC_CustomerId_I
WHERE
  REC_Active_c='y'
  AND REC_SalesMasterId_I='0'
ORDER BY REC_Id_I

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通过使用select语句，我解决了我的问题

代码是：

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若要计算聚合函数并获取相应的列值，必须将GROUP BY中的所有其他列（计算聚合的列除外）

SELECT table_1.column_A,
       MAX(table_2.column_B),
       table_2.column_C

FROM table_1
     INNER JOIN table_2   ON table_1.column_A=table_2.column_B

GROUP BY table_1.column_A,
         table_2.column_C

---

MSSQL不是MySQL。您需要显式地按列分组。@Juhana错误消息表明它是MSSQL。MySQL只是隐式地按列分组。就像在其他地方使用GROUP BY一样。我使用GROUP BY，即使它显示错误

SELECT table_1.column_A,
       MAX(table_2.column_B),
       table_2.column_C

FROM table_1
     INNER JOIN table_2   ON table_1.column_A=table_2.column_B

GROUP BY table_1.column_A,
         table_2.column_C