新创建用户ysq ，密码yang123.可以远程连接，只有查询权限

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> select host ,user  from user;
+-----------+------------------+
| host      | user             |
+-----------+------------------+
| %         | myuser           |
| 127.0.0.1 | root             |
| ::1       | root             |
| localhost | debian-sys-maint |
| localhost | root             |
+-----------+------------------+
5 rows in set (0.00 sec)

mysql> CREATE USER 'ysq'@'%' IDENTIFIED BY 'yang123';
Query OK, 0 rows affected (0.00 sec)

mysql> GRANT select ON *.* TO 'ysq'@'%';
Query OK, 0 rows affected (0.00 sec)

mysql> select host,user from user;
+-----------+------------------+
| host      | user             |
+-----------+------------------+
| %         | myuser           |
| %         | ysq              |
| 127.0.0.1 | root             |
| ::1       | root             |
| localhost | debian-sys-maint |
| localhost | root             |
+-----------+------------------+
6 rows in set (0.00 sec)

mysql> SHOW GRANTS FOR 'ysq'@'%';
+-----------------------------------------------------------------------------------------------------+
| Grants for ysq@%                                                                                    |
+-----------------------------------------------------------------------------------------------------+
| GRANT SELECT ON *.* TO 'ysq'@'%' IDENTIFIED BY PASSWORD '*D3AE29C9A53A4FA000DFBBE948F8A23FDA9AAF33' |
+-----------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

mysql>