查找重复的电子邮箱
https://leetcode-cn.com/problems/duplicate-emails/
内连接,或者多表查询
email 相同,但是 id 不同的行
select
????distinct?p1.Email
from
????Person?p1
????inner?join?Person?p2?on?p1.Id?<>?p2.Id
????and?p1.Email?=?p2.Email
原文:https://www.cnblogs.com/wudanyang/p/13124492.html