[프로그래머스/MySQL] 입양 시각 구하기(1)

https://programmers.co.kr/learn/courses/30/lessons/59412?language=mysql

HOUR(DATETIME) 을 하면 해당 DATETIME의 시간만 출력이 된다.

SELECT HOUR(DATETIME) AS HOUR, COUNT(1) as COUNT
 FROM ANIMAL_OUTS
 GROUP BY 1
 HAVING HOUR >= 9 AND HOUR < 20
 ORDER BY 1;