[프로그래머스] 오랜 기간 보호한 동물(1)(MySQL)

문제 링크 - https://school.programmers.co.kr/learn/courses/30/lessons/59044

풀이

SELECT INS.NAME, INS.DATETIME
FROM ANIMAL_INS INS LEFT OUTER JOIN ANIMAL_OUTS OUTS ON INS.ANIMAL_ID = OUTS.ANIMAL_ID
WHERE OUTS.ANIMAL_ID IS NULL
ORDER BY INS.DATETIME
LIMIT 3