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我有一个包含客户详细信息的表“客户”和一个存储每个电话结果的表“呼叫”

当我需要获取必须致电的客户列表时，我会使用此查询

SELECT *
FROM (
    SELECT TOP (50) S.ID,S.URL,S.Phone,S.Email
    FROM dbo.Customers AS S
    WHERE URL is not null and City like 'Berl%'
    ORDER BY S.ID 
    ) AS S

OUTER APPLY (
SELECT TOP (3) I.CalledOn, I.Answer
FROM dbo.Calls AS I
WHERE S.URL = I.URL
ORDER BY I.CalledOn DESC
) AS I;

在那里我得到了城市中所有客户的名单以及最后 3 个答案。

但这会为每个客户返回最多 3 条记录，而我只有一条并将 CalledOn 和 Answer 的 3 个值汇总到同一条记录中

更清楚的是：现在：

+-----------+---------------+-------------+------------------+
|Customer 1 |  555-333 333  | 02-10-17    | Call Tomorrow    |
+-----------+---------------+-------------+------------------+
|Customer 2 |  555-444 333  | 02-10-17    | Call Tomorrow    |
+-----------+---------------+-------------+------------------+
|Customer 1 |  555-333 333  | 02-11-17    | Call Tomorrow    |
+-----------+---------------+-------------+------------------+
|Customer 1 |  555-333 333  | 02-12-17    | Stop Calling     |
+-----------+---------------+-------------+------------------+

预期的

+-----------+---------------+--------------------------------+
|Customer 1 |  555-333 333  | 02-12-17 : Call Stop Calling   |
|           |               | 02-11-17 : Call Tomorrow       |
|           |               | 02-10-17 : Call Tomorrow       |
+-----------+---------------+-------------+------------------+
|Customer 2 |  555-444 333  | 02-10-17    | Call Tomorrow    |
+-----------+---------------+-------------+------------------+

目前我正在使用服务器端逻辑来实现这一点，但我确信它可以通过 TSQL 以更简单和更好的方式完成

可以建议方向吗？

谢谢

4

1 回答 1

1

对于 SQL-Server 2012

SELECT TOP (50) S.ID, S.URL, S.Phone, S.Email,
           STUFF((SELECT CHAR(10) + concat (I.CalledOn, ' ', I.Answer)
                  FROM dbo.Calls AS I
                  WHERE S.URL = I.URL
                  ORDER BY I.CalledOn DESC
                  FOR XML PATH('')
                ), 1, 1, '') AS CallAnswer
FROM dbo.Customers AS S
WHERE URL is not null and City like 'Berl%'
ORDER BY S.ID

v下一个：

SELECT TOP (50) S.ID, S.URL, S.Phone, S.Email,
           (SELECT TOP (3) STRING_AGG(CONCAT(I.CalledOn, ' ', I.Answer), CHAR(13))
            FROM dbo.Calls AS I
            WHERE S.URL = I.URL
            ORDER BY I.CalledOn DESC
           ) AS CallAnswer
FROM dbo.Customers AS S
WHERE URL is not null and City like 'Berl%'
ORDER BY S.ID

在这里检查：http ://rextester.com/HSIEL20631

于 2017-02-16T08:49:09.097 回答