mysql> select version();
+-----------+
| version() |
+-----------+
| 8.0.12    |
+-----------+
1行记录(0.14秒)

CREATE USER 'yourUserName'@'localhost' IDENTIFIED BY 'yourPassword';

GRANT ALL ON *.* TO 'yourUserName'@'localhost';

flush privileges;

mysql> use MySQL;
Database changed
mysql> CREATE USER 'James'@'localhost' IDENTIFIED BY 'James123456';
Query OK, 0 rows affected (0.21 sec)

mysql> GRANT ALL ON *.* TO 'James'@'localhost';
Query OK, 0 rows affected (0.18 sec)

mysql> select user from MySQL.user;

+------------------+
| user             |
+------------------+
| Bob              |
| Manish           |
| User2            |
| mysql.infoschema |
| mysql.session    |
| mysql.sys        |
| root             |
| @UserName@       |
| Adam Smith       |
| James            |
| John             |
| John Doe         |
| User1            |
| am               |
| hbstudent        |
| mysql.infoschema |
| mysql.session    |
+------------------+
17 rows in set (0.00 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.04 sec)