I have the same question... it seems that they don't accept 'delete from' statement? I'm confused.
It mentions "Currently, you cannot delete from a table and select from the same table in a subquery." in MySQL manual. So it will give below error:
delete from Person where Id not in (select min(Id) from Person group by Email);
ERROR 1093 (HY000): You can't specify target table 'Person' for update in FROM clause
But there's a workaround for subquery. I copied from another question.
delete from Person where id not in (select id from (select min(id) as id from Person group by email) as a);
The nested subquery in the FROM clause creates an implicit temporary table, so it doesn't count as the same table you're deleting.