LeetCode - 182. Duplicate Emails (MySQL)

Easy, SQL - 중복값 찾기

RunTime : 874 ms

문제

Write a solution to report all the duplicate emails.
Note that it's guaranteed that the email field is not NULL.

Return the result table in any order.

The result format is in the following example.

풀이

• 전체 데이터들 중 중복되는 데이터들을 찾을 땐 GROUP BY + HAVING으로 찾을 수 있다.

SELECT email FROM Person
GROUP BY email
HAVING COUNT(email) > 1