> For the complete documentation index, see [llms.txt](https://dfine.gitbook.io/leetcode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dfine.gitbook.io/leetcode/182.duplicate_emails.md).

# 182.Duplicate Emails

**182.Duplicate Emails**

难度:Easy

> SQL架构 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> | +---------+ 说明：所有电子邮箱都是小写字母。 代码：

```
# Write your MySQL query statement below
select Email from Person  group by Email having count(Email)>1;
```


---

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