대여 기록이 존재하는 자동차 리스트 구하기

https://school.programmers.co.kr/learn/courses/30/lessons/157341

• 문제 풀이

SELECT C.CAR_ID
FROM CAR_RENTAL_COMPANY_CAR C
	   JOIN CAR_RENTAL_COMPANY_RENTAL_HISTORY H
		 ON C.CAR_ID = H.CAR_ID 
WHERE C.CAR_TYPE = '세단' AND TO_CHAR(H.START_DATE, 'MM') = '10'
GROUP BY C.CAR_ID
ORDER BY C.CAR_ID DESC;

SELECT DISTINCT C.CAR_ID
FROM (
    SELECT CAR_ID 
    FROM CAR_RENTAL_COMPANY_CAR
    WHERE CAR_TYPE = '세단'
) C
INNER JOIN CAR_RENTAL_COMPANY_RENTAL_HISTORY H
ON C.CAR_ID = H.CAR_ID
WHERE TO_CHAR(H.START_DATE, 'MM') = '10'
ORDER BY C.CAR_ID DESC;

• 실행 결과