Mysql删除重复数据保留最小的id 的解决方法

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:

 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

delete from tb where id=xx

是个笨方法,暂时先解决问题吧。

总结

以上所述是小编给大家介绍的Mysql删除重复数据保留最小的id 的解决方法,希望对大家有所帮助,如果大家有任何疑问欢迎给我留言,小编会及时回复大家的!

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