입양 시각 구하기(2)

문제

코드

SELECT HOUR, COUNT(ANIMAL_ID) AS COUNT
FROM ( SELECT (ROW_NUMBER() OVER () - 1) AS HOUR
       FROM ANIMAL_OUTS
       LIMIT 24) AS 24HOURS_NUM_TABLE 
     LEFT JOIN ANIMAL_OUTS ON HOUR = HOUR(DATETIME)
GROUP BY HOUR
ORDER BY HOUR

 

출처: 프로그래머스 코딩 테스트 연습, https://school.programmers.co.kr/learn/courses/30/lessons/59413