Mysql刪除重複資料保留最小的id

在網路上尋找刪除重複資料保留id最小的數據，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
)

自己使用的時候顯示報錯：

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

暫時不知道是什麼原因導致的。

然後想辦法分散操作，先篩選出有重複user的數據，然後用max()選出其中較大的那一行：

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

然後再根據得到的max(id)逐條刪除多餘的資料

1 delete from tb where id=xx

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