我已经安装了mysql服务器和mysql工作台。我需要使用workbench接口连接到mysql。我以前在windows中很容易做到这一点，因为服务器的安装也是在图形用户界面中进行的。
但现在我在ubuntu18机器上工作。当我尝试在进入 root 密码我得到这个错误：
我执行此命令以确保密码正确：

mysql> UPDATE mysql.user set authentication_string = PASSWORD('mypass') where user = 'root' and host = 'localhost';
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 1

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

mysql> exit()

然后，当我尝试此操作并输入密码时，再次出现错误：

x@x-VirtualBox:~$ mysql -u root -p -h > localhost -P 3306
Enter password: 
ERROR 2005 (HY000): Unknown MySQL server host '-P' (2)

谁能告诉我怎么了吗？如何建立数据库连接？
编辑：服务肯定正在运行。以下是测试：

x@x-VirtualBox:~$ service mysql status
● mysql.service - MySQL Community Server
   Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: en
   Active: active (running) since Sat 2018-07-28 20:54:14 WIB; 6min ago
  Process: 12790 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/run/mysqld/m
  Process: 12779 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exi
 Main PID: 12792 (mysqld)
    Tasks: 28 (limit: 4915)
   CGroup: /system.slice/mysql.service
           └─12792 /usr/sbin/mysqld --daemonize --pid-file=/run/mysqld/mysqld.pi

Jul 28 20:54:13 e-VirtualBox systemd[1]: Starting MySQL Community Server...
Jul 28 20:54:14 e-VirtualBox systemd[1]: Started MySQL Community Server.

编辑2：使用命令行，我输入根密码，它工作。但是工作台不接受它。

sudo mysql -u root -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 11
Server version: 5.7.22-0ubuntu18.04.1 (Ubuntu)

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