Leetcode Database SQL Delete Duplicate Emails

Leetcode Original Quote:

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

  +----+------------------+| Id | Email |+----+------------------+| 1 | [Email protected] | | 2 | [Email protected] | | 3 | [email protected] |+----+------------------+id is the primary key, column for this table.   

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

+----+------------------+| Id | Email            |+----+------------------+| 1  | [Email protected] | | 2  | [email protected]  | +----+------------------+

My SQL statement:

DELETE from the person WHERE the ID is not in    (the Select         ID from        (select             MIN (ID) as ID        from the person GROUP by email) as a);

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Leetcode Database SQL Delete Duplicate Emails