https://school.programmers.co.kr/learn/courses/30/lessons/59410
SELECT
animal_type,
CASE WHEN name is null THEN 'No name'
ELSE name END AS name,
sex_upon_intake
FROM
animal_ins
ORDER BY
animal_id;
다른 사람 풀이
SELECT ANIMAL_TYPE, IFNULL(NAME, 'No name'), SEX_UPON_INTAKE FROM ANIMAL_INS
ORDER BY ANIMAL_ID;
CASE.. WHEN..쓰는 문제였음
근데 다른 사람 풀이보니,
IFNULL(NAME, 'No name')도 있더라