如何组合2个SQL查询并检索累积计数？

我正在尝试检索特定A/B测试组合每天的访问次数和转化次数.每种组合代表A/B测试的不同变化.在这里,我只使用'1'并'2'代表变化,但从技术上讲,可能会有更多的变化.

我写了以下2个查询,它们独立工作.是否可以组合这些或写一个检索我想要的数据的查询？

访问查询:

SELECT DATE(visit.created), visit.combination, COUNT(visit.id) 
FROM visit 
WHERE visit.user_id = 6
AND visit.experiment_id = 1
GROUP BY DATE(visit.created), visit.combination

访问结果:

转化查询:

SELECT DATE(conversion.created), conversion.combination, COUNT(conversion.id) 
FROM conversion 
WHERE conversion.user_id = 6
AND conversion.experiment_id = 1
AND conversion.goal_id = 1
GROUP BY DATE(conversion.created), conversion.combination

转化结果:

如果我可以检索一个正在运行的总计(累计)计数,如下所示,请查看最后两列.我已经按照组合对下表进行了分组,因此累积计数更容易理解:

+---------------+-------------+----------------------+-----------------+--------------+--------------+
| DATE(created) | combination | COUNT(conversion.id) | COUNT(visit.id) | cumulative_c | cumulative_v |
+---------------+-------------+----------------------+-----------------+--------------+--------------+
| 2015-11-17    | 1           |                    1 |               3 |            1 |            3 |
| 2015-11-18    | 1           |                    7 |               4 |            8 |            7 |
| 2015-11-19    | 1           |                    3 |               8 |           11 |           15 |
| 2015-11-17    | 2           |                    4 |               1 |            4 |            1 |
| 2015-11-18    | 2           |                    2 |               6 |            6 |            7 |
| 2015-11-19    | 2           |                    9 |               6 |           15 |           13 |
+---------------+-------------+----------------------+-----------------+--------------+--------------+

数据库架构: