[Programmers][SQL] 입양 시각 구하기(2) (59413번) - MySQL Solution

문제

• https://programmers.co.kr/learn/courses/30/lessons/59413

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Solution

SET @hour := -1;

SELECT (@hour := @hour +1) AS 'HOUR',
(SELECT COUNT(*) FROM ANIMAL_OUTS WHERE HOUR(DATETIME) = @hour) AS COUNT
FROM ANIMAL_OUTS WHERE @hour < 23;