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LeetCode Duplicate Emails

Problem

Write a SQL query to find all duplicate emails in a table named Person.

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+----+---------+
| Id | Email   |
+----+---------+
| 1  | a@b.com |
| 2  | c@d.com |
| 3  | a@b.com |
+----+---------+

For example, your query should return the following for the above table:

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+---------+
| Email   |
+---------+
| a@b.com |
+---------+

找到重复的Email。

MySQL

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SELECT Email FROM Person GROUP BY Email HAVING COUNT(Email) > 1;

分析

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