LeetCode Delete Duplicate Emails

Problem

Write a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id.

+----+------------------+
| Id | Email            |
+----+------------------+
| 1  | john@example.com |
| 2  | bob@example.com  |
| 3  | john@example.com |
+----+------------------+
Id is the primary key column for this table.

For example, after running your query, the above Person table should have the following rows:

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

删除邮件重复的记录，保留Id最小的

MySQL

DELETE p1 FROM Person p1, Person p2 WHERE p1.Email = p2.Email AND p1.Id > p2.Id;

分析

无

所有代码已上传至Github：https://github.com/lihongzheshuai/yummy-code

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