mysql查询删除重复数据

从一张表查询 数据 插入到另一张表
insert into tp_wxaccount(`appid`,`appsecret`,`name`,`num`,`time`,`state`,`uid`) select  appid,appsecret,name,num,time,state,uid  from tp_wxaccount1

查找重复的数据
Select * From tp_wxaccount Where appid In (Select appid From tp_wxaccount Group By appid Having Count(*)>1)



删除重复的数据只保留一条
delete tp_wxaccount1 where id not in (select max(id) from tp_wxaccount1 group by appid //这样会报错 不能自己查询自己再删除自己



删除重复的数据只保留一条
delete from tp_wxaccount1 where id not in ( select * from (select  max(id) from tp_wxaccount1 a group by a.appid )a)

删除重复的数据只保留一条
delete from tp_wxaccount2 where id not in ( select * from (select  max(id) from tp_wxaccount2  group by appid )as c)

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转载自blog.csdn.net/ljwy1234/article/details/81068897