题目:
题目链接: https://leetcode-cn.com/problems/duplicate-emails/
解题思路:
group by + having组合使用
SQL:
select Email from
(select Email, count(*) as num from Person group by Email having num > 1) a
题目链接: https://leetcode-cn.com/problems/duplicate-emails/
group by + having组合使用
select Email from
(select Email, count(*) as num from Person group by Email having num > 1) a