首先使用命令进入数据库
[root@localhost raul]# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 3
Server version: 5.1.73 Source distribution
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affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
然后切换数据库，进入我们须要操作的数据库mysql
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
删除之前我们先查看一下数据库的用户表，看看用户的存在情况
mysql> select user, host from user;
+------+-----------------------+
| user | host |
+------+-----------------------+
| root | 127.0.0.1 |
| | localhost |
| root | localhost |
| | localhost.localdomain |
| root | localhost.localdomain |
+------+-----------------------+
5 rows in set (0.00 sec)
我们看到啦，在user这一列有的行是空的。这就是那个匿名用户啦～。在这一步我们已经找到匿名用户啦，剩下的操作就是删除掉这个用户，保证登录安全
mysql> delete from user where user='';
Query OK, 2 rows affected (0.00 sec)
此时mysql运行的状态显示我们删除了两行数据，然后运行一边查询命令，确认一下是不是真的删除成功啦？
mysql> select user, host from user;
+------+-----------------------+
| user | host |
+------+-----------------------+
| root | 127.0.0.1 |
| root | localhost |
| root | localhost.localdomain |
+------+-----------------------+
3 rows in set (0.00 sec)