[SQL문제풀기 - Advent of SQL 2025 🎅] 레스토랑의 주중, 주말 매출액 비교하기

문제

solvesql.com

https://solvesql.com/problems/revenue-weekday-weekend/

내가 작성한 정답

MySQL, SQLite, PostgreSQL

select week, sum(total_bill) sales
from (select case when day in ('Sun','Sat')  then 'weekend'
           else 'weekday' end week,
       total_bill
      from tips) w
group by week
order by 2 desc;