2022-04-07 sql count group by

count(*) 配合 group by 属性1,属性2 按照属性分组并统计个数

1693. 每天的领导和合伙人

select date_id,make_name, 
count(distinct lead_id) as unique_leads ,
count(distinct partner_id) as unique_partners
from DailySales group by date_id,make_name;

1141. 查询近30天活跃用户数

select activity_date as day,count(*) as active_users  from
(select distinct user_id,activity_date from Activity
where
(select TIMESTAMPDIFF(DAY,activity_date ,"2019-07-27")<30)
and activity_date<="2019-07-27"
)t
group by activity_date
order by activity_date;