Mysql删除重复数据保留最小的id

在网上查找删除重复数据保留id最小的数据，方法如下：

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
)

自己使用的时候显示报错：

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

暂时不知道是什么原因导致的。

然后想办法分布操作，首先筛选出有重复user的数据，然后用max()选出其中较大的那一行：

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

然后再根据得到的max(id)逐条删除多余的数据

1 delete from tb where id=xx

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