Write a SQL query to find all duplicate emails in a table named Person.
+----+---------+
| Id | Email |
+----+---------+
| 1 | [email protected] |
| 2 | [email protected] |
| 3 | [email protected] |
+----+---------+For example, your query should return the following for the above table:
+---------+
| Email |
+---------+
| [email protected] |
+---------+解題：按照Email分組，然後找出id出現次數超過1的Email。
SQL語句使用group by 和 having 實現：
select Email from Person group by Email having count(id) > 1;