[프로그래머스] Lv3. 헤비 유저가 소유한 장소

문제

https://school.programmers.co.kr/learn/courses/30/lessons/77487

프로그래머스

 

• host_id 가 2개 이상인 데이터 조

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정답코드

# 1
SELECT id, name, host_id
FROM PLACES
WHERE host_id IN (SELECT host_id FROM places 
                  GROUP BY host_id 
                  HAVING COUNT(host_id) > 1)
ORDER BY ID

# 2 -- JOIN문
SELECT T1.ID, T1.NAME, T1.HOST_ID
FROM PLACES T1 JOIN (SELECT ID, HOST_ID, COUNT(*) AS 'COUNT' 
			FROM PLACES GROUP BY HOST_ID) T2 
	ON T1.HOST_ID = T2.HOST_ID 
WHERE T2.COUNT > 1
ORDER BY T1.ID