这是我的设置：
Emails_Table
| ID | user_id | campaign_id | status | date |
---------------------------------------------------------------------------
| 100 | 7 | 12 | sent | 2017-05-29 |
| 101 | 8 | 11 | sent | 2017-06-19 |
| 104 | 9 | 14 | fail | 2017-06-22 |
| 105 | 7 | 12 | fail | 2017-07-17 |
| 107 | 9 | 14 | fail | 2017-07-25 |
| 108 | 7 | 15 | sent | 2017-12-10 |
| 109 | 9 | 2 | others | 2018-01-02 |
| 110 | 9 | 17 | sent | 2018-01-11 |
| 111 | 9 | 14 | fail | 2018-01-22 |
Users_Table
| user_id | username |
---------------------------
| 5 | john |
| 7 | james |
| 8 | maria |
| 9 | rex |
Campaigns_Table
| campaign_id | campaign_name |
---------------------------------------
| 2 | Sample 2nd Campaign |
| 11 | Sample 11 |
| 12 | Twelve |
| 14 | Sample #14 |
| 15 | Lala Campaign |
| 17 | Meow Campaign |
| 18 | Cat GIFs Campaign |
我怎样才能得到这样的结果？我正在使用日期范围进行过滤，记录按user_id分组。
Result
| user_id | username | total_sent | total_failed |
---------------------------------------------------
| 7 | james | 2 | 1 |
| 8 | maria | 1 | 0 |
| 9 | rex | 1 | 3 |
我的起始查询结构如下：
SELECT Emails_Table.user_id, username, COUNT/SUM(total_sent), COUNT/SUM(total_failed)
FROM Emails_Table
LEFT JOIN Users_Table ON Emails_Table.user_id=Users_Table.user_id
WHERE (date BETWEEN 2017-05-29 AND 2018-01-22)
GROUP BY user_id
如您所见，我很难实现COUNT / SUM（total_sent）和COUNT / SUM（total_failed）。有人可以建议我如何实现这个目标吗？