MySQL 8.0 误删了root用户折腾记

背景：最新想尝鲜安装下ubuntu 20.04，默认mysql版本为8.0，一不小心把root用户给删除了，开始折腾。

一、修改配置文件

在配置文件/etc/mysql/conf.d/mysql.cnf中增加2行

[mysqld]
skip-grant-tables 

重启mysql服务：

sudo systemctl restart mysql.service

登录mysql，分别执行以下几行code

use mysql;
insert into user(User,authentication_string,ssl_cipher,x509_issuer,x509_subject) values('root','','','','');
update user set Host='localhost',select_priv='y', insert_priv='y',update_priv='y',Alter_priv='y',delete_priv='y',create_priv='y',drop_priv='y',reload_priv='y',shutdown_priv='y',Process_priv='y',file_priv='y',grant_priv='y',References_priv='y',index_priv='y',create_user_priv='y',show_db_priv='y',super_priv='y',create_tmp_table_priv='y',Lock_tables_priv='y',execute_priv='y',repl_slave_priv='y',repl_client_priv='y',create_view_priv='y',show_view_priv='y',create_routine_priv='y',alter_routine_priv='y',create_user_priv='y' where user='root';commit;

二、修改配置为正常再修改root密码

将密码修改成root@12345

mysql
use mysql;
alter user 'root'@'localhost' identified with mysql_native_password by 'root@12345';