Create table If Not Exists Person (id int, email varchar(255))
Truncate table Person
insert into Person (id, email) values ('1', 'a@b.com')
insert into Person (id, email) values ('2', 'c@d.com')
insert into Person (id, email) values ('3', 'a@b.com')
编写一个 SQL 查询,查找 Person 表中所有重复的电子邮箱。
示例:
±—±--------+
| Id | Email |
±—±--------+
| 1 | a@b.com |
| 2 | c@d.com |
| 3 | a@b.com |
±—±--------+
根据以上输入,你的查询应返回以下结果:
±--------+
| Email |
±--------+
| a@b.com |
±--------+
说明:所有电子邮箱都是小写字母。
来源:力扣(LeetCode)
链接:https://leetcode.cn/problems/duplicate-emails
方法一:使用GROUP BY和HAVING字句
MySQL提交内容:
# Write your MySQL query statement below
select Email
from Person
group by Email
having count(Email) > 1;