Ubuntu安装MySQL 8.0.21更改默认用户密码

• 查看初始密码
  初始密码存放在/etc/mysql/debian.cnf文件中

/etc/mysql$ sudo cat debian.cnf
# Automatically generated for Debian scripts. DO NOT TOUCH!
[client]
host     = localhost
user     = debian-sys-maint
password = OSozOdppag50NmbG
socket   = /var/run/mysqld/mysqld.sock
[mysql_upgrade]
host     = localhost
user     = debian-sys-maint
password = OSozOdppag50NmbG
socket   = /var/run/mysqld/mysqld.sock

• 用初始账号密码登录

/etc/mysql$ mysql -u debian-sys-maint -p
Enter password: OSozOdppag50NmbG

• 修改密码
  注意：老的语句已经不行了 update user set authentication_string=password(“newPassword”) where user=“root”;

mysql> use mysql;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123456';// 123456为新密码
Query OK, 0 rows affected (0.01 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

mysql> quit;
Bye

• 重新登录

mysql -uroot -p