Mysql 多个条件下的聚合值

根据下表

+-----------+-------------+----------+
|   tours   |  tour_user  | tag_tour |
+-----------+-------------+----------+
| id        | tour_id     | tag_id   |
| startdate | user_id     | tour_id  |
+-----------+-------------+----------+

我希望实现如下结果集：

+-----------------+----------------+----------------+
| DATE(startdate) | COUNT(user_id) | COUNT(tour_id) |
+-----------------+----------------+----------------+
| 2017-12-01      |             55 |             32 |
+-----------------+----------------+----------------+

用文字描述参与一次旅行的用户数量和旅行数量应按天数汇总

此外，旅游和用户参与的计数应可通过标签过滤，标签通过tag_tour table many to may关系附在旅游上。 例如，我只需要附加tag_id 1和2的旅游和旅游用户计数

目前我支持以下查询：

SELECT DATE(tours.start) AS acum_date,
   COUNT(tour_user.user_id) AS guide_assignments,
   A.tour_count
FROM `tour_user`
LEFT JOIN `tours` ON `tours`.`id` = `tour_user`.`tour_id`
LEFT JOIN
      (SELECT DATE(tours.start) AS tour_date,
      COUNT(DISTINCT tours.id) AS tour_count
FROM tours
GROUP BY DATE(tours.start)) AS A ON `A`.`tour_date` = DATE(tours.start)
GROUP BY `acum_date`
ORDER BY `acum_date` ASC

问题是，只返回巡更/用户总数，而不返回过滤后的总数。

基本查询是：

select t.startdate, count(tu.user_id) as num_users, count(distinct t.id) as num_tours
from tours t left join
     tour_user tu
     on tu.tour_id = t.id
group by t.startdate;

在这种情况下，我建议使用exists来过滤标记：

select t.startdate, count(tu.user_id) as num_users, count(distinct t.id) as num_tours
from tours t left join
     tour_user tu
     on tu.tour_id = t.id
where exists (select 1 from tour_tags tt where tt.tour_id = t.tid and tt.tag_id = <tag1>) and
      exists (select 1 from tour_tags tt where tt.tour_id = t.tid and tt.tag_id = <tag2>)       
group by t.startdate;

---

添加一些样本数据和匹配的预期结果。你已经尝试了什么，你在哪里卡住了？我附上了我的当前状态，非常感谢你！工作起来很有魅力：-