Write a SQL query to delete all duplicate email entries in a table named
Person, 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 above
Person table should have the following rows:+----+------------------+ | Id | Email | +----+------------------+ | 1 | john@example.com | | 2 | bob@example.com | +----+------------------+
Solution: DELETE p1 FROM Person p1 join Person p2 WHERE p1.Email = p2.Email AND p1.Id > p2.Id
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