182.duplicate-emails.0.sql

--
-- @lc app=leetcode id=182 lang=mysql
--
-- [182] Duplicate Emails
--
-- https://leetcode.com/problems/duplicate-emails/description/
--
-- database
-- Easy (53.31%)
-- Total Accepted:    107.9K
-- Total Submissions: 200.9K
-- Testcase Example:  '{"headers": {"Person": ["Id", "Email"]}, "rows": {"Person": [[1, "a@b.com"], [2, "c@d.com"], [3, "a@b.com"]]}}'
--
-- 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.
--
--
SELECT Email FROM
    (SELECT Email, Count(*) as Count FROM Person GROUP BY Email) AS Person2
WHERE Person2.Count > 1