182. Duplicate Emails#2

Solutin#1

SELECT Email FROM (SELECT Email, COUNT(Email) AS Cnt FROM Person GROUP BY Email) T WHERE Cnt > 1

Solutin#2()

SELECT Email FROM Person GROUP BY Email HAVING COUNT(Email) > 1

Problem
1. Mysql：Windows表名不区分大小写，Linux区分；字段都不区分大小写
2. 子查询临时表必须有别名
3. WHERE 和 HAVING区别