문제
SELECT O.ANIMAL_ID, O.NAME
FROM ANIMAL_OUTS O
LEFT JOIN ANIMAL_INS I ON (I.ANIMAL_ID = O.ANIMAL_ID)
WHERE I.ANIMAL_ID IS NULL;
Convinced myself, I seek not to convince.
SELECT O.ANIMAL_ID, O.NAME
FROM ANIMAL_OUTS O
LEFT JOIN ANIMAL_INS I ON (I.ANIMAL_ID = O.ANIMAL_ID)
WHERE I.ANIMAL_ID IS NULL;