Leetcode182查找重复的电子邮箱

182查找重复的电子邮箱

编写一个 SQL 查询，查找 Person 表中所有重复的电子邮箱。

SQL Schema

Create table If Not Exists Person (id int, email varchar(255))
Truncate table Person
insert into Person (id, email) values ('1', 'a@b.com')
insert into Person (id, email) values ('2', 'c@d.com')
insert into Person (id, email) values ('3', 'a@b.com')

示例：

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

根据以上输入，你的查询应返回以下结果：

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

说明：所有电子邮箱都是小写字母。

Solution 1

-- mysql # Write your MySQL query statement below
select email as Email
from Person
group by email
having count(*) >= 2;