CROSS APPLY返回逗号分隔值以及GROUP BY

Posted 2021-04-02

我正在处理一个查询，以返回一个报告，该报告将每个业务单位的日志记录分组，同时分配给每个业务单位的经理分隔的管理员列表，所以基本上有4个表。

[dbo].[Log]
[dbo].[BusinessUnit]
[dbo].[Manager]
[dbo].[BusinessUnitManager]

为了报告，BusinessUnit，Manager和BusinessUnitManager只是用于访问基本信息的表，我需要分组的真实信息包含在Log表中，我的最终结果集应该如下所示：

BusinessUnit.Name,
Log.Code,
Count(*) LogRecordsCount,
Emails (Comma separated list of Managers assigned to the Business Unit)

我一直在尝试使用CROSS APPLY获取逗号分隔列但无法使其正常工作，我当前的查询如下所示：

SELECT
L.BusinessUnit,
L.Code, 
COUNT(*) AS RecordsCount,
F.Emails
FROM [dbo].[LOG] AS L
INNER JOIN [dbo].[BusinessUnit] AS D ON L.BusinessUnit = D.ID
INNER JOIN [dbo].[BusinessUnitManager] AS DSO ON D.ID = DSO.BusinessUnit
CROSS APPLY
(
    SELECT STUFF((
    SELECT ',' + O.Email
    FROM [dbo].[Manager] AS O
    WHERE O.Id = DSO.IdManager
    ORDER BY O.Email ASC
    FOR XML PATH ('')), 1, 1, '')
) F(Emails)
GROUP BY L.BusinessUnit, L.Code, F.Emails

此查询的问题是返回重复的行，每个管理器电子邮件分配给业务单位一行，我的预期结果应该只有一行，其中一列包含所有管理员电子邮件的逗号分隔列表。

目前的结果：

+--------------+------+--------------+----------------------------+
| BusinessUnit | Code | RecordsCount |           Emails           |
+--------------+------+--------------+----------------------------+
| Americas     |   00 |           21 | [e-mail] |
| Americas     |   00 |           21 | [e-mail] |
| Asia         |   10 |            5 | [e-mail]     |
| Asia         |   10 |            5 | [e-mail]     |
+--------------+------+--------------+----------------------------+

预期结果：

+--------------+------+--------------+-------------------------------------------------------+
| BusinessUnit | Code | RecordsCount |                        Emails                         |
+--------------+------+--------------+-------------------------------------------------------+
| Americas     |   00 |           21 | [e-mail],[e-mail] |
| Asia         |   10 |            5 | [e-mail],[e-mail]         |
+--------------+------+--------------+-------------------------------------------------------+

我将感激你的帮助

答案

你很接近，只需两步即可：

1）将您的东西存储到临时表中

SELECT
L.BusinessUnit,
L.Code, 
O.Emails
into #tmp
FROM [dbo].[LOG] AS L
INNER JOIN [dbo].[BusinessUnit] AS D ON L.BusinessUnit = D.ID
INNER JOIN [dbo].[BusinessUnitManager] AS DSO ON D.ID = DSO.BusinessUnit
JOIN [Manager] AS O ON O.Id = DSO.IdManager
GROUP BY L.BusinessUnit, L.Code, O.Emails

2）使用外部申请自己在一栏中填写电子邮件

select BusinessUnit,Code, F.Emails from #tmp t 
outer apply( 
     SELECT STUFF(( SELECT ',' + inner.Email 
     FROM #tmp inner 
     WHERE t.Id = inner. 
     ORDER BY O.Email ASC 
     FOR XML PATH ('')), 1, 1, '') 
) F(Emails) 
group by BusinessUnit,Code

另一答案

SELECT
    L.BusinessUnit,
    L.Code, 
    COUNT(*) AS RecordsCount,
    (
        SELECT STUFF((
        SELECT ',' + O.Email
        FROM [dbo].[Manager] AS O
            INNER JOIN [dbo].[BusinessUnitManager] AS DSO ON O.Id = DSO.IdManager 
        WHERE 
            DSO.BusinessUnit = D.ID
        ORDER BY O.Email ASC
        FOR XML PATH ('')), 1, 1, '')
    ) as Emails
FROM [dbo].[LOG] AS L
    INNER JOIN [dbo].[BusinessUnit] AS D ON L.BusinessUnit = D.ID
GROUP BY L.BusinessUnit, L.Code, D.ID