SQL: 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。

示例：

+----+---------+
| Id | Email   |
+----+---------+
| 1  | [email protected] |
| 2  | [email protected] |
| 3  | [email protected] |
+----+---------+
根据以上输入，你的查询应返回以下结果：

+---------+
| Email   |
+---------+
| [email protected] |
+---------+
说明：所有电子邮箱都是小写字母。

select
    Email
from
    (
        select
            Email,
            count(*) count
        from
            Person
        group by Email
    ) t
where t.count > 1

或者

select
    Email
from
    Person
group by Email
having(count(Email)) > 1