Delete Duplicate Emails

Desicription

Write a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id.

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+----+------------------+
| Id | Email |
+----+------------------+
| 1 | john@example.com |
| 2 | bob@example.com |
| 3 | john@example.com |
+----+------------------+
Id is the primary key column for this table.

For example, after running your query, the above Person table should have the following rows:

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+----+------------------+
| Id | Email |
+----+------------------+
| 1 | john@example.com |
| 2 | bob@example.com |
+----+------------------+

Solution

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# Write your MySQL query statement below
DELETE
P1
FROM
Person P1, Person P2
WHERE
P1.Email = P2.Email AND
P1.Id > P2.Id