LeetCode Delete Duplicate Emails, leetcodeduplicate

LeetCode Delete Duplicate Emails, leetcodeduplicate

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 shoshould have the following rows:

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

In this case, there will be errors:

delete from Person where id not in (select max(a.id) as id from Person a group by email);

Runtime Error Message:	You can't specify target table 'body' for update in FROM clause
Last executed input:	{"Headers": {"Person": ["Id", "Email"]}, "rows": {"Person": []}

AC:

delete from Person where id not in (select id as id from (select min(b.id) as id from Person b group by email) as a);