安装mysql后必做的两件事

1..删除掉不需要的用户

查看用户表
mysql> SELECT User,Host FROM mysql.user;
+------+-------------------------+
| User | Host                    |
+------+-------------------------+
| root | 127.0.0.1               |
|      | izwz9cl4i8oy1reej7o8pmz |
| root | izwz9cl4i8oy1reej7o8pmz |
|      | localhost               |
| root | localhost               |
+------+-------------------------+
5 rows in set (0.00 sec)

删除用户最好再SELECT一次，以免删除错误
mysql> SELECT User,Host FROM mysql.user WHERE User="";
+------+-------------------------+
| User | Host                    |
+------+-------------------------+
|      | izwz9cl4i8oy1reej7o8pmz |
|      | localhost               |
+------+-------------------------+
2 rows in set (0.00 sec)

删除用户
mysql> DELETE FROM mysql.user WHERE User="";
Query OK, 2 rows affected (0.00 sec)

mysql> 

2..设置密码

对root用户设置密码
mysql> UPDATE mysql.user SET PASSWORD=PASSWORD("syj2FBZ") WHERE User='root';
Query OK, 3 rows affected (0.00 sec)
Rows matched: 3  Changed: 3  Warnings: 0

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

退出
mysql> quit
Bye

测试无密码登录
[root@iZwz9cl4i8oy1reej7o8pmZ ~]# mysql
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
[root@iZwz9cl4i8oy1reej7o8pmZ ~]# 

测试使用密码登录
[root@iZwz9cl4i8oy1reej7o8pmZ ~]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.1.73 Source distribution

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mysql>