SQL Schema
Write a SQL query to find all duplicate emails in a table named Person.
±—±——–+
| Id | Email |
±—±——–+
| 1 | a@b.com |
| 2 | c@d.com |
| 3 | a@b.com |
±—±——–+
For example, your query should return the following for the above table:
±——–+
| Email |
±——–+
| a@b.com |
±——–+
Note: All emails are in lowercase.
好久没写sql，很多写法都记不起来，本题解法如下：
select distinct p1.Email from Person p1, Person p2 where p1.Email = p2.Email and (p1.Id > p2.Id or p1.Id < p2.Id)
此写法速度超过92.86%，存储用量低于100%的解法
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