196_Delete Duplicate Emails

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

+----+------------------+
| 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 abovePersontable should have the following rows:

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

Solution: self join

DELETE p1 
FROM Person AS p1,
     Person AS p2
WHERE
    p1.Email = p2.Email 
    AND p1.Id > p2.Id
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