Mysql删除重复数据保留最小的id 的解决方法
16lz
2021-12-29
在网上查找删除重复数据保留id最小的数据,方法如下:
DELETEFROM peopleWHERE 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)
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
delete from tb where id=xx
总结
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