SQL Server DISTINCT OR GROUP BY WITH TEMP TABLES

Question

我有一个复杂的问题。这个想法是，我需要一个表中不同的 Serv_Acct（这很简单，我已经有了）：

DECLARE 

 @CustomerID int = 8,
 @UtilityCompanyID int = 1


    SELECT DISTINCT SERV_ACCT, MAX(INV_DATE)
    FROM tblAPSData

    WHERE SERV_ACCT NOT IN (SELECT ServiceAccount
                FROM tblMEP_Meters
                JOIN tblMEP_Sites
                ON tblMEP_Meters.SiteID = tblMEP_Sites.ID

                JOIN tblMEP_Projects
                ON tblMEP_Projects.ID = tblMEP_Sites.ProjectID

                WHERE CustomerID = 8
                AND Type = 1
                )

    AND ACCOUNT IN (SELECT AccountNumber
                    FROM tblMEP_CustomerAccounts
                    WHERE CustomerID = @CustomerID
                    AND UtilityCompanyID = @UtilityCompanyID)

    AND INV_DATE > DATEADD(month, -6, getdate())
    GROUP BY SERV_ACCT

当我运行这个时，我得到 16 行：

SERV_ACCT   (No column name)
0289S61288  2013-06-12 00:00:00.000
0492S90281  2013-06-12 00:00:00.000
1303S90280  2013-06-12 00:00:00.000
1435S01282  2013-06-12 00:00:00.000
1440S13289  2013-06-24 00:00:00.000
1548S00286  2013-06-12 00:00:00.000
2498S21288  2013-06-12 00:00:00.000
5384S92284  2013-06-24 00:00:00.000
5538S21284  2013-06-12 00:00:00.000
6109S12286  2013-06-12 00:00:00.000
7358S00281  2013-06-12 00:00:00.000
7488S22289  2013-06-12 00:00:00.000
8058S12287  2013-06-12 00:00:00.000
9058S00288  2013-06-12 00:00:00.000
9168S00282  2013-06-12 00:00:00.000
9645S21281  2013-06-12 00:00:00.000

现在，我没有得到的部分是，每个服务帐户都有一个帐号，有些服务帐户有多个帐号，我只想要一个具有最新日期的帐号的服务帐户。当我尝试这样做时看到问题：

DECLARE 

 @CustomerID int = 8,
 @UtilityCompanyID int = 1


    SELECT DISTINCT SERV_ACCT, ACCOUNT, MAX(INV_DATE)
    FROM tblAPSData

    WHERE SERV_ACCT NOT IN (SELECT ServiceAccount
                FROM tblMEP_Meters
                JOIN tblMEP_Sites
                ON tblMEP_Meters.SiteID = tblMEP_Sites.ID

                JOIN tblMEP_Projects
                ON tblMEP_Projects.ID = tblMEP_Sites.ProjectID

                WHERE CustomerID = 8
                AND Type = 1
                )

    AND ACCOUNT IN (SELECT AccountNumber
                    FROM tblMEP_CustomerAccounts
                    WHERE CustomerID = @CustomerID
                    AND UtilityCompanyID = @UtilityCompanyID)

    AND INV_DATE > DATEADD(month, -6, getdate())
    GROUP BY SERV_ACCT, ACCOUNT
    ORDER BY SERV_ACCT

现在结果如下：

SERV_ACCT   ACCOUNT (No column name)
0289S61288  117512280   2013-06-12 00:00:00.000
0492S90281  117512280   2013-06-12 00:00:00.000
0492S90281  651412281   2013-04-08 00:00:00.000
1303S90280  117512280   2013-06-12 00:00:00.000
1435S01282  117512280   2013-06-12 00:00:00.000
1440S13289  312937281   2013-06-24 00:00:00.000
1548S00286  117512280   2013-06-12 00:00:00.000
1548S00286  308710287   2013-04-08 00:00:00.000
2498S21288  117512280   2013-06-12 00:00:00.000
5384S92284  979437282   2013-06-24 00:00:00.000
5538S21284  117512280   2013-06-12 00:00:00.000
6109S12286  117512280   2013-06-12 00:00:00.000
7358S00281  117512280   2013-06-12 00:00:00.000
7358S00281  659710281   2013-04-08 00:00:00.000
7488S22289  117512280   2013-06-12 00:00:00.000
8058S12287  117512280   2013-06-12 00:00:00.000
9058S00288  117512280   2013-06-12 00:00:00.000
9168S00282  117512280   2013-06-12 00:00:00.000
9168S00282  570810282   2013-04-08 00:00:00.000
9645S21281  117512280   2013-06-12 00:00:00.000

如您所见，Serv_Acct 不再是 Distinct 了！我的目标是仅使用最新帐户获得不同的 Serv_Acct（即 16）。关于如何做到这一点的任何帮助？我问了一个朋友，她告诉我，我可以用临时表来做到这一点！真的吗？

Answer 1

尝试使用您列为子查询的第一个查询，并将其连接到 tblapsdata。它看起来像这样：

DECLARE 

 @CustomerID int = 8,
 @UtilityCompanyID int = 1

SELECT MD.SERV_ACCT, AD.ACCOUNT, MD.MAXINVDATE
FROM
(SELECT DISTINCT SERV_ACCT, MAX(INV_DATE) as MAXINVDATE
FROM tblAPSData

WHERE SERV_ACCT NOT IN (SELECT ServiceAccount
            FROM tblMEP_Meters
            JOIN tblMEP_Sites
            ON tblMEP_Meters.SiteID = tblMEP_Sites.ID

            JOIN tblMEP_Projects
            ON tblMEP_Projects.ID = tblMEP_Sites.ProjectID

            WHERE CustomerID = 8
            AND Type = 1
            )

AND ACCOUNT IN (SELECT AccountNumber
                FROM tblMEP_CustomerAccounts
                WHERE CustomerID = @CustomerID
                AND UtilityCompanyID = @UtilityCompanyID)

AND INV_DATE > DATEADD(month, -6, getdate())
GROUP BY SERV_ACCT) MD
join tblAPSdata AD on MD.SERV_ACCT = AD.SERV_ACCT and MD.MAXINVDATE = AD.INV_DATE

请注意，这只会返回原始查询中的记录，但会附加相应的帐号。请注意，如果您有多个具有相同日期的帐号，则会返回更多记录。