SQL练习题：回购率 复购率 消费差异

SQL练习题：回购率 复购率 消费差异

统计不同月份的下单人数

select month(paidTime),count(distinct userid)
from data.orderinfor
where isPaid = '已支付'
group by month(paidTime);

统计用户三月份的回购率和复购率

1、复购率：这个月份中所有消费人数中消费以上的举手

select count(ct),count(if(ct>1, 1, null)) from (
	select userId, count(userId) as ct
	from data.orderinfor
	where isPaid = '已支付' and month(paidTime) = 3
	group by userId) t;

2、回购率：上个月份购买的人数这个月份依旧购买
(1) 得到每个用户在哪个时间消费过

select userId, date_format(paidTime,'%Y-%m-01') from data.orderinfor 
where idPaid = '已支付'
group by userId, date_format(paidTime,'%Y-%m-01')

select * 
from t1
left join
t2 on t1.userId = t2.userID;

select * 
from t1
left join
t2 on t1.userId = t2.userID 
and t1.m = date_sub(t2.m, interval 1 month) ;

select t1.m, count(t1.m), count(t2.m)
from t1
left join
t2 on t1.userId = t2.userID 
where t1.m = date_sub(t2.m, interval 1 month) 
group by t1.m;

统计男女用户的消费频次是否有差异

就是男生平均消费多少次，女生平均消费多少次

select avg() over(partition by a.sex ) from 
	(select * from data.userinfor
	where sex <> '') a;

统计多次消费的用户，第一次和最后一次消费间隔是多少

max min datediff

统计不同年龄段，用户的消费金额是否有差异

case when 年龄

统计消费的二八法则，消费的top20%的用户，贡献了多少额度

ntile(5) over order by