LeetCode 182. Duplicate Emails (查找重复的电子邮箱)

题目标签：

　　题目给了我们一个 email 的table，让我们找到重复的 email。

　　可以建立 Person a， Person b，找到两个表格中，emai 相等但是 id 不同的 email，然后利用DISTINCT 返回，因为两个表格中，会找到两个重复的email。

Java Solution:

Runtime: 224 ms, faster than 40 %

Memory Usage: N/A

完成日期：06/01/2019

关键点：用DISTINCT

# Write your MySQL query statement below
SELECT DISTINCT a.Email
FROM Person a, Person b
WHERE a.Email = b.Email AND a.Id != b.Id

参考资料：n/a

LeetCode 题目列表 - LeetCode Questions List

题目来源：https://leetcode.com/

原文地址：https://www.cnblogs.com/jimmycheng/p/11444495.html

时间： 2024-10-01 03:37:42

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