Mysql deletes duplicate data and keeps the smallest ID

Find and delete duplicate data on the Internet and keep the data with the smallest ID. The method is as follows:

DELETE FROM people WHERE peopleName IN ( SELECT peopleName FROM people GROUP BY peopleName HAVING count(peopleName) > 1 ) AND peopleId NOT IN ( SELECT min(peopleId) FROM people GROUP BY peopleName HAVING count(peopleName) > 1 )

When you use it yourself, an error message is displayed:

1 delete from tb where id in (SELECT max(id) from tb GROUP BY user HAVING count(user)>1)

[Err] 1093 - You can't specify target table 'XXX' for update in FROM clause

I don’t know what the cause is yet.

Then find a way to distribute the operations, first filter out the data with duplicate users, and then use max() to select the larger row:

SELECT max(id) from tb GROUP BY user HAVING count(user)>1

Then delete the redundant data one by one based on the obtained max(id)

1 delete from tb where id=xx

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