在 MS Access 中计算开始日期和结束日期之间的不同项目

Question

我有这两张表：

表 1

| EventCode | StartDate |  EndDate  | Client |
|   13400   | 1/12/2014 | 5/12/2014 |   ABC  |
|   13400   | 6/12/2014 | 8/12/2014 |   ABC  |
|   15600   | 3/12/2014 | 5/12/2014 |   ABC  |

表 2

| EventCode | Client | SignUpDate | Agent |
|   13400   |   ABC  |  2/12/2014 | AG001 |
|   13400   |   ABC  |  2/12/2014 | AG001 |
|   13400   |   ABC  |  3/12/2014 | AG002 |
|   15600   |   ABC  |  4/12/2014 | AG002 |
|   15600   |   ABC  |  4/12/2014 | AG004 |
|   15600   |   ABC  |  5/12/2014 | AG002 |
|   13400   |   ABC  |  7/12/2014 | AG003 |

我需要加入两个表 WHERE Table2.SignUpDate BETWEEN Table1.StartDate AND Table1.EndDate，然后我需要表 2 中 distinct 的 Agent 计数，以获取每个事件有多少不同的人进行了销售，如下所示：

| EventCode | StartDate |  EndDate  | Client |  CountOfDistinctAgents |
|   13400   | 1/12/2014 | 5/12/2014 |   ABC  |           2            | //(AG001, AG002)
|   13400   | 6/12/2014 | 8/12/2014 |   ABC  |           1            | //(AG003)
|   15600   | 3/12/2014 | 5/12/2014 |   ABC  |           2            | //(AG002, AG004)

但我无法获得上述输出，因为我需要在 MS ACCESS 2003 中执行此操作。 请帮我。

这是我的旧代码，但不包括 DISTINCT 代理。

SELECT tmp.[Event Code], eb.CampaignLN, eb.StartDate, eb.EndDate, COUNT(*) AS HeadCount
FROM 
(SELECT DISTINCT [Event Code], Campaign, [Signup Date], [Agent Id] FROM [Main Table2]) AS tmp 
INNER JOIN qryGetEventBookings AS eb ON (tmp.[Signup Date] BETWEEN CDATE(eb.StartDate) AND  
CDATE(eb.EndDate)) AND (eb.CampaignLN=tmp.Campaign) AND (eb.LocationCode=tmp.[Event Code])
GROUP BY tmp.[Event Code], eb.CampaignLN, eb.StartDate, eb.EndDate;

非常感谢您的所有帮助。提前致谢。

Answer 1

要计算不同的代理，您需要使用子查询（因为 MS Access 不支持count(distinct)）。结果是这样的：

SELECT [Event Code], COUNT(*) AS NumAgents
FROM (SELECT DISTINCT m.EventCode, eb.Agent
      FROM  [Main Table2] as m JOIN
            qryGetEventBookings eb
            ON eb.CampaignLN = m.Campaign AND eb.LocationCode = m.[Event Code] AND
               eb.SignUpDate BETWEEN m.StartDate AND m.EndDate
     ) AS tmp 
GROUP BY [Event Code];