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 | 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 | +---------+
# Write your MySQL query statement below select Email from person group by email having count(email)>1;
原文：https://www.cnblogs.com/JAYPARK/p/10289184.html