182.(Easy)查找重复的电子邮箱
+----+---------+
| Id | Email |
+----+---------+
| 1 | a@b.com |
| 2 | c@d.com |
| 3 | a@b.com |
+----+---------++---------+
| Email |
+---------+
| a@b.com |
+---------+
说明:所有电子邮箱都是小写字母。Solution
Last updated
+----+---------+
| Id | Email |
+----+---------+
| 1 | a@b.com |
| 2 | c@d.com |
| 3 | a@b.com |
+----+---------++---------+
| Email |
+---------+
| a@b.com |
+---------+
说明:所有电子邮箱都是小写字母。Last updated
select Email
from Person
group by 1
having count(1)>1