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.

1 # Write your MySQL query statement below
2 SELECT DISTINCT a.Email 
3 FROM Person a, Person b
4 WHERE a.Email = b.Email AND a.Id != b.Id;

182. Duplicate Emails

原文：https://www.cnblogs.com/hyxsolitude/p/12299184.html