【发布时间】:2020-04-20 15:37:59
【问题描述】:
【问题讨论】:
-
数据库是什么?
-
这里的大多数人都希望样本表数据和预期结果为格式化文本,而不是图像。
【问题讨论】:
一个合理的选择是相关子查询:
select
t1.*,
(
select sum(t2.new_users)
from table_2
where
t2.campaignid = t1.campaignid
and t2.date between t1.sentdate and t1.enddate
) new_users
from table_1 t1
【讨论】:
加入和聚合就可以了:
select
a.sentdate, a.enddate, a.campaignid, a.sent,
sum(b.New_Users) as New_Users
from table1 a
join table2 b on b.date >= a.sentdate and b.date <= a.enddate
and b.campaignid = a.campaignid
group by a.sentdate, a.enddate, a.campaignid, a.sent
【讨论】: