大数据第35天—Mysql练习题6-杨大伟

需求：编写一个 SQL 查询，查找 Person 表中所有重复的电子邮箱。

展示效果：

Email

a@b.com

Create table If Not Exists Person (Id int, Email varchar(255))

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')

 

最终SQL:

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