leetcode-182-Duplicate-Emails

发表于   |  

描述

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

1
2
3
4
5
6
7
+----+---------+
| 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:

1
2
3
4
5
+---------+
| Email   |
+---------+
| a@b.com |
+---------+

分析

找出重复的 Email

解决方案(MySQL)

1
2
3
4
5
6
# Write your MySQL query statement below
SELECT 
Email
FROM Person
GROUP BY Email
Having COUNT(*) > 1

题目来源