Question

我相信这对你们大多数人来说都是一个非常简单的问题，但它让我疯狂...... 我有一个这样的表（简化）：

| customer_id | date | purchase amount |

我需要每天提取当天购买的客户数量，以及在当前购买前30天内至少进行购买的客户数量。

我尝试使用这样的子查询：

select purch_date as date, count (distinct customer_id) as DAU, 
   count(distinct (select customer_id from table where purch_date<= date and purch_date>date-30)) as MAU
from table
group by purch_date

Netezza返回错误，指出不支持子查询，我应该考虑重写查询。但是如何？！？！？我尝试使用case when语句，但没有用。事实上，以下内容：

select purch_date as date, count (distinct customer_id) as DAU, 
   count(distinct case when (purch_date<= date and purch_date>date-30) then player_id else null end) as MAU
from table
group by purch_date

没有返回错误，但是MAU和DAU列是相同的（这是错误的）。请问有人帮帮我吗？非常感谢

Answer 1

我终于明白了:)对于所有感兴趣的人，这是我解决它的方式：

select a.date_dt, max(a.dau), count(distinct b.player_id)
from (select dt.cal_day_dt as date_dt, 
        count(distinct s.player_id) as dau
        FROM IA_PLAYER_SALES_HOURLY s
        join IA_DATES dt on dt.date_key = s.date_key
        group by dt.cal_day_dt
        order by dt.cal_day_dt
) a
join (
        select dt.cal_day_dt as date_dt, 
        s.player_id as player_id
        FROM IA_PLAYER_SALES_HOURLY s
        join IA_DATES dt on dt.date_key = s.date_key
        order by dt.cal_day_dt
) b on b.date_dt <= a.date_dt and b.date_dt > a.date_dt - 30
group by a.date_dt
order by a.date_dt;

希望这有用。

Answer 2

我不相信netezza支持选择行中的子查询...转到from语句

 select pur_date as date, count(distinct customer_id) as DAU
 from table
 group by purch_date

 select pur_date as date, count (distinct customer_ID) as MAU
 from table
 where purch_date<= date and purch_date>date-30
 group by purch_date

我希望这对于MAU和DAU是正确的。加入他们以获得结果：

 select a.date, a.dau, b.mau
 from
 (select pur_date as date, count(distinct customer_id) as DAU
 from table
 group by purch_date) a

 left join 
 (select pur_date as date, count (distinct customer_ID) as MAU
 from table
 where purch_date<= date and purch_date>date-30
 group by purch_date) b

 on b.date = a.date

Netezza不支持子查询和类似...任何解决方法？

2 个答案: