[LeetCode MySQL] 182. Duplicate Emails

2021. 2. 10. 13:39Today I Learned.../MySQL

182. Duplicate Emails

Write a SQL query to find all duplicate emails in a table named Person.

+----+---------+
| Id | Email   |
+----+---------+
| 1  | a@b.com |
| 2  | c@d.com |
| 3  | a@b.com |
+----+---------+

 

For example, your query should return the following for the above table:

 

+---------+
| Email   |
+---------+
| a@b.com |
+---------+

Note: All emails are in lowercase.

 

Solution

select email
from person
group by email
having count(*) >= 2

Reference: LeetCode 182. Duplicate Emails