solvesql 연습문제 실습

select d.order_date as dt, count(distinct d.customer_id) as dau, count(distinct w.customer_id) as wau, round(count(distinct d.customer_id) / count(distinct w.customer_id),2) as stickiness from records d left join records w on w.order_date between date_add(d.order_date, interval - 6 day) and d.order_date where d.order_date between '2020-11-01' and '2020-11-30' group by d.order_date order by dt;