[LeetCode]Duplicate Emails,解题报告

题目

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

Id	Email
1	[email protected]
2	[email protected]
3	[email protected]

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

Email
[email protected]

Note: All emails are in lowercase.

解题思路

题目需要从Person表中找出重复出现的Email。

解题方法也很简单：按照Email分组，然后找出id出现次数超过1的Email，即使用group by 和 having 实现。

AC SQL

select Email from Person group by Email having count(id) > 1;

时间： 2024-11-01 13:23:29

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[LeetCode]Duplicate Emails,解题报告

目录

题目

解题思路

AC SQL

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