구름 아카이브

Combine Two Tables
https://leetcode.com/problems/Combine-Two-Tables/

SELECT firstName, lastName, city, state             
FROM Person
     LEFT JOIN Address ON Person.personId =Address.personId
     
    
    
# {"headers": 

# ["firstName", "lastName", "city", "state"], 

# "values": 

# [["Allen", "Wang", null, null], 
# ["Bob", "Alice", "New York City", "New York"]]}

*** 다시 풀어볼 것

Delete Duplicate Emails.   - delete에 조인 활용하기 >>> 각각 지울 꺼 조인 활용해서 한번에 몰아서 지우는 방식
https://leetcode.com/problems/Delete-Duplicate-Emails/

https://leetcode.com/problems/Delete-Duplicate-Emails/

# email 가지고 group by를 한 뒤, 이 이메일이 가지고 있는 id값이 무엇이냐
# WHERE 절에 들어간 min ID들을 제외하고 삭제
# 서브쿼리가 동작하지 않음

DELETE >>> 지울 테이블 지정(조인을 활용 할 경우)
FROM Person >>> 삭제를 해주고 싶은 테이블 명
WHERE Id NOT IN
(

SELECT sub.min_id
FROM(

SELECT Email, MIN(id) AS min_id
FROM Person
GROUP BY Email
) sub 

)