設定密碼

1. 預設 root 沒密碼，可直接登入。

   [root@kvm3 ~]# mariadb -uroot
   Welcome to the MariaDB monitor.  Commands end with ; or \g.
   Your MariaDB connection id is 5
   Server version: 10.5.16-MariaDB MariaDB Server
   
   Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
   
   Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
   
   MariaDB [(none)]> quit
   Bye
   

2. 免密碼登入 mariadb，設定 root 的密碼為 123qwe，並更新權限表。

   [root@kvm3 ~]# mariadb -uroot
   Welcome to the MariaDB monitor.  Commands end with ; or \g.
   Your MariaDB connection id is 31
   Server version: 10.5.16-MariaDB MariaDB Server
   
   Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
   
   Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
   
   MariaDB [(none)]> alter user 'root'@'localhost' identified by '123qwe';
   Query OK, 0 rows affected (0.067 sec)
   
   MariaDB [(none)]> flush privileges;
   Query OK, 0 rows affected (0.052 sec)
   
   MariaDB [(none)]> quit;
   Bye
   

3. 再免密碼登入 mariadb，回應存取限制。

   [root@kvm3 ~]# mariadb -uroot
   ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
   

4. 以設定的密碼 123qwe 成功登入 mariadb。

   [root@kvm3 ~]# mariadb -uroot -p123qwe
   Welcome to the MariaDB monitor.  Commands end with ; or \g.
   Your MariaDB connection id is 33
   Server version: 10.5.16-MariaDB MariaDB Server
   
   Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
   
   Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
   
   MariaDB [(none)]> quit
   Bye