[SQL문제풀기] 데이터 그룹으로 묶기

문제

solvesql.com

https://solvesql.com/problems/group-by/

SQLite

내가 작성한 정답

select quartet, round(avg(x),2) x_mean, round(var_samp(x),2) x_var,
                round(avg(y),2) y_mean, round(var_samp(y),2) y_var
from points
group by quartet