์ผ๋จ ํ ์ด๋ธ์ ์๊น์๋ฅผ ๋ณด๊ณ ์ถ์ด ํ ์ด๋ธ์ JOIN ํด๋ดค๋๋ฐ, ํ ์ชฝ ํ ์ด๋ธ์๋ ๋ฐ์ดํฐ๊ฐ ์๋๋ฐ, ๋๋จธ์ง ํ ์ด๋ธ์๋ JOIN ๋๋ฉด์ NULL ๊ฐ๋ค์ด ์๊ฒผ๋ค. ํ ์ชฝ ํ ์ด๋ธ์๋ ๋ฐ์ดํฐ๊ฐ ์๋๋ฐ ๋ค๋ฅธ ํ๋์๋ ์๋ ๋ฐ์ดํฐ๋ฅผ ์กฐํํ๋ ค๋ฉด?
๊ทธ๋ฌ๋ฉด OUTER JOIN ์ ํ๋ ค๋ฉด ์ด๋ป๊ฒ ์ฟผ๋ฆฌ๋ฅผ ๋ง๋ค์ด์ผ ํ ๊น?
SELECT
ao.ANIMAL_ID,
ao.NAME
FROM ANIMAL_INS ai
RIGHT JOIN ANIMAL_OUTS ao
ON ai.ANIMAL_ID = ao.ANIMAL_ID
WHERE ai.ANIMAL_ID IS NULL
ORDER BY 1;
์ฐธ๊ณ : https://velog.io/@ehdtkd98/ํ๋ก๊ทธ๋๋จธ์ค์์ด์ง-๊ธฐ๋ก-์ฐพ๊ธฐ-SQL-lhk0b7wy
๋ฌธ์์ด ์ฌ๋ผ์ด์ฑ์ผ๋ก ๋ค์ง๋ ๋ฐฉ๋ฒ: [::-1]
์ฐธ๊ณ : https://velog.io/@ehdtkd98/ํ๋ก๊ทธ๋๋จธ์คํธ๋-ํ์ดํธ-๋ํ-ํ์ด์ฌ