[root@sample ~]# yum -y install mysql-server ← 安装MySQL
然后，安装PHP访问MySQL数据库的工具“php-mysql”
[root@sample ~]# yum -y install php-mysql ← 安装php-mysql
2、配置MySQL
[root@sample ~]# vi /etc/my.cnf ← 编辑MySQL的配置文件
#定位到这里
[client]
#password = your_password
port = 3306
socket = /tmp/mysql.sock
default-character-set = utf8
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Default to using old password format for compatibility with mysql 3.x
# clients (those using the mysqlclient10 compatibility package).
old_passwords=1 ← 找到这一行，在这一行的下面添加新的规则，让MySQL的默认编码 为UTF-8(假若找不到，就在本文件到底添加)
default-character-set = utf8 ← 添加这一行
启动MySQL服务，进入MySQL里面运行status查看是否已经全部都是支持了utf8，并让MySQL在系统重新启动后随系统自动启动。
[root@sample ~]# chkconfig mysqld on ← 设置MySQL服务随系统启动自启动
[root@sample ~]# chkconfig --list mysqld ← 确认MySQL自启动
mysqld 0:off 1:off 2:on 3:on 4:on 5:on 6:off ← 如果2--5为on的状态就OK
[root@sample ~]# service mysqld start ← 启动MySQL服务
3、设置root用户密码及相关优化配置
MySQL在刚刚被安装的时候，它的root用户是没有被设置密码的，首先来设置MySQL的root密码。
[root@sample ~]# mysql -u root ← 用root用户登录MySQL服务器
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2 to server version: 4.1.20
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> select user,host,password from mysql.user; ← 查看用户信息
+------+------------------------------+---------------+
| user | host | password |
+------+------------------------------+---------------+
| root | localhost | | ← root密码为空
| root | sample.centospub.com | | ← root密码为空
| | sample.centospub.com | |
| | localhost | |
+------+------------------------------+---------------+
4 rows in set (0.00 sec)
mysql> set password for root@localhost=password('yournewpwd'); ← 设置root密码
Query OK, 0 rows affected (0.01 sec)
mysql> set password for root@'sample.centospub.com'=password('newID'); ← 设置root密码
Query OK, 0 rows affected (0.01 sec)
mysql> select user,host,password from mysql.user; ← 查看用户信息
+------+--------------------------------+--------------------------+
| user | host | password |
+------+--------------------------------+--------------------------+
| root | localhost | 19b68057189b027f | ← root密码被设置，已经加密
| root | sample.centospub.com | 19b68057189b027f | ← root密码被设置，已经加密
| | sample.centospub.com | |
| | localhost | |
+------+--------------------------------+--------------------------+
4 rows in set (0.01 sec)
mysql> exit ← 退出MySQL服务器
Bye
然后，测试一下root密码有没有生效。
[root@sample ~]# mysql -u root ← 通过空密码用root登录
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO) ← 出现此错误信息说明密码设置成功
[root@localhost ~] # mysql -u root -h sample.centospub.com ← 通过空密码用root登录
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO) ← 出现此错误信息说明密码设置成功
[root@sample ~]# mysql -u root -p ← 通过密码用root登录
Enter password: ← 在这里输入密码
Welcome to the MySQL monitor. Commands end with ; or \g. ← 确认用密码能够成功登录
Your MySQL connection id is 5 to server version: 4.1.20
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> exit
[root@sample ~]# mysql -u root -h sample.centospub.com -p ← 通过密码用root登录
Enter password: ← 在这里输入密码
Welcome to the MySQL monitor. Commands end with ; or \g. ← 确认用密码能够成功登录
Your MySQL connection id is 6 to server version: 4.1.20
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> exit ← 退出MySQL服务器
Bye
删除匿名用户
在MySQL刚刚被安装后，存在用户名、密码为空的用户。这使得数据库服务器有无需密码被登录的可能性，为消除隐患，将匿名用户删除。
[root@sample ~]# mysql -u root -p ← 通过密码用root登录
Enter passwor