Delete Duplicate Emails
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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 |
+—-+——————+
DELETE FROM Person WHERE ID NOT IN (SELECT * FROM (SELECT MIN(Id) FROM Person p GROUP BY Email) t);
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