[SQL] 오랜 기간 보호한 동물(2) - LEFT JOIN 예시

SELECT ins.ANIMAL_ID, ins.NAME
FROM ANIMAL_INS ins
LEFT JOIN ANIMAL_OUTS outs
    ON ins.ANIMAL_ID =  outs.ANIMAL_ID
WHERE outs.DATETIME IS NOT NULL
ORDER BY outs.DATETIME - ins.DATETIME DESC
limit 2