通过代码
select
start_month,
mau,
month_add_uv,
max(month_add_uv)over(order by start_month),
sum(month_add_uv)over(order by start_month )
from(
select
date_format(start_time,'%Y%m') start_month,
count(distinct uid) mau,
count(distinct IF((date_format(start_time, '%Y%m'), uid) in
(select
min(date_format(start_time, '%Y%m')),
uid
from
exam_record
group by uid
), uid,null)) month_add_uv
from
exam_record
group by
start_month
)t
order by
start_month
其实这道题也没多难,就是这个题目解释的活跃矩阵给我带坑里去了,我一直在想怎么把这个活跃矩阵给整出来,结果直接卡死在了动态行转列,qaq有大佬能给孩子讲讲怎么动态行转列吗??