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# 196.(Easy)删除重复的电子邮箱

编写一个 SQL 查询，来删除 Person 表中所有重复的电子邮箱，重复的邮箱里只保留 Id 最小 的那个。

```
+----+------------------+
| Id | Email            |
+----+------------------+
| 1  | john@example.com |
| 2  | bob@example.com  |
| 3  | john@example.com |
+----+------------------+
Id 是这个表的主键。
例如，在运行你的查询语句之后，上面的 Person 表应返回以下几行:

+----+------------------+
| Id | Email            |
+----+------------------+
| 1  | john@example.com |
| 2  | bob@example.com  |
+----+------------------+
```

提示：

执行 SQL 之后，输出是整个 `Person` 表。使用 `delete` 语句。

来源：力扣（LeetCode）

链接：<https://leetcode-cn.com/problems/delete-duplicate-emails>

著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。

## Solution

```sql
-- Select p1.* from Person p1, Person p2 where p1.Email=p2.Email and p1.Id>p2.Id

delete p1 
from Person p1, Person p2 
where p1.Email=p2.Email and p1.Id>p2.Id
```


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