错误：表“p”缺少 FROM 子句条目

Question

我正在尝试使用 UNION 将前半部分的总列附加到查询的后半部分。

SELECT NULL as month, NULL as active, count(cage_player_id) as total
FROM player_signup as p 
GROUP BY date_part('month', p.signup_date)

UNION 

SELECT date_part('month', signup_date) as month, count(DISTINCT(p.cage_player_id)) as active, NULL as total
FROM player_signup as p
JOIN daily_kpis as d ON p.cage_player_id = d.cage_player_id
WHERE slot_bet_amount > 0
OR ld_bet_amount > 0 
OR table_bet_amount > 0 
GROUP BY date_part('month', p.signup_date)
ORDER BY date_part('month', p.signup_date) ASC

我不断收到错误消息，提示表 p 缺少 FROM 子句。任何人都可以帮忙吗？有没有更简单的方法来组合这两个查询？

这是每个查询分别显示的样子。我只想在月份和活动列旁边添加总计列。总 ID 仍将按月细分。

查询 1

查询 2

Answer 1

问题在于order by 子句。它适用于 union 查询的 results，因此它看不到查询中定义的标识符。相反，您应该使用结果集中列的名称。

所以你想改变这个：

ORDER BY date_part('month', p.signup_date) ASC

收件人：

ORDER BY month

Answer 2

我相信这是您需要的查询：

SELECT date_part('month', signup_date) as month
       , count(DISTINCT(p.cage_player_id)) as active
       , (select count(cage_player_id) 
          FROM player_signup as p 
          GROUP BY date_part('month', p.signup_date)) as total
FROM player_signup as p
JOIN daily_kpis as d ON p.cage_player_id = d.cage_player_id
WHERE slot_bet_amount > 0
OR ld_bet_amount > 0 
OR table_bet_amount > 0 
GROUP BY date_part('month', p.signup_date)
ORDER BY date_part('month', p.signup_date) asc

我不太擅长 Postgresql，请试试这个：

SELECT date_part('month', signup_date) as month
       , count(DISTINCT(p.cage_player_id)) as active
       , max(t1.total) as total
FROM player_signup as p
left join (select count(pp.cage_player_id) over (partition by date_part('month', pp.signup_date)) as total
                  , date_part('month', pp.signup_date) date_p
           FROM player_signup as pp) t1 on t1.date_p = date_part('month', p.signup_date)
JOIN daily_kpis as d ON p.cage_player_id = d.cage_player_id
WHERE slot_bet_amount > 0
OR ld_bet_amount > 0 
OR table_bet_amount > 0 
GROUP BY date_part('month', p.signup_date)
ORDER BY date_part('month', p.signup_date)