使用union或join添加两个查询的结果

Question

我有两个使用union结合的mysql查询。我得到了我想要的结果。但是，我想知道是否有办法组合具有相同名称的字段。例如，我从图像中的第一个表中获取结果。我想要做的是梳理名为＆＃34; test＆＃34;的两个促销字段。进入一个字段并添加三列（free，none，pay）。我想要的结果在第二个表中。

这是我的查询

 select users.refer as promo, 
                            count( case when plan = 'free' then 1  end ) as free,
                            count( case when plan = '' then 1 end ) as none,
                            count( case when plan <> 'free' and plan <> '' then 1 end) as pay,
                            promos.status as status
                            from users
                            inner join promos on users.refer = promos.name
                            where refer <> ''
                            group by refer
Union 
select subscriptions.promo as promo,
                            count( case when plan = 'free' then 1  end ) as free,
                            count( case when plan = '' then 1 end ) as none,
                            count( case when plan <> 'free' and plan <> '' then 1 end) as pay,
                            promos.status as status
                            from subscriptions
                            inner join promos on subscriptions.promo = promos.name
                            inner join users on subscriptions.user_id = users.id
                            where promo <> ''
                            group by promo

Answer 1

将查询放入子查询中，然后使用SUM()和GROUP BY。

SELECT promo, SUM(free) AS free, SUM(none) AS none, SUM(pay) AS pay, MAX(status) AS status
FROM ( put your query here ) AS subquery
GROUP BY promo