[Input - GA]

[Problem]
- 00시부터 23시까지 시간대별로 "page_view" 이벤트가 발생한 수를 카운트하시오.
[Output]

[Answer]
set @hour:= -1;
select (@hour:= @hour + 1) as hr
,(select count(1) from ga where hour(event_timestamp_kst) = @hour and event_name = "page_view") as cnt
from ga
where 1=1
and @hour < 23;