(三)centos7下安裝MariaDB 10.0/MySQL數據庫

CentOS/RHEL 6 或早期的版本中提供的是 MySQL 的服務器/客戶端安裝包，但 CentOS/RHEL 7 已使用了
MariaDB 替代了默認的 MySQL。作爲 MySQL 的簡單替代品，MariaDB 保證了與 MySQL 的 API
和命令行用法方面最大的兼容性。下面是關於怎麼在 CentOS 上安裝和配置 MaraDB/MySQL 的操作示例。

1、查看系統版本

# cat /etc/redhat-release 
CentOS Linux release 7.3.1611 (Core) 

2、獲取包源（更換源）

來自官網的包源 https://downloads.mariadb.org/mariadb/repositorie

# cd /etc/yum.repos.d
# cat >> MariaDB.repo <<EOF
# MariaDB 10.0 CentOS repository list - created 2016-03-29 03:06 UTC
# http://mariadb.org/mariadb/repositories/
[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/10.0/centos7-amd64
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1
EOF

3、安裝

安裝之前確保機器上面沒有YUM安裝的MySQL

# rpm -qa | grep -i mysql
or 
# yum remove $(rpm -qa | grep -i mysql )
# yum install MariaDB-server MariaDB-client

4、啓動

# systemctl start mysql.service(啓動)
# systemctl enable mysql.service（開機啓動）

如出現此：

使用：

# /sbin/chkconfig mysql on（上面若不行可用此開機啓動）

5、設置root密碼

#mysql_secure_installation

NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB
      SERVERS IN PRODUCTION USE!  PLEASE READ EACH STEP CAREFULLY!

In order to log into MariaDB to secure it, we'll need the current
password for the root user.  If you've just installed MariaDB, and
you haven't set the root password yet, the password will be blank,
so you should just press enter here.

Enter current password for root (enter for none): 
OK, successfully used password, moving on...

Setting the root password ensures that nobody can log into the MariaDB
root user without the proper authorisation.

Set root password? [Y/n] y
New password: 
Re-enter new password: 
Password updated successfully!
Reloading privilege tables..
 ... Success!


By default, a MariaDB installation has an anonymous user, allowing anyone
to log into MariaDB without having to have a user account created for
them.  This is intended only for testing, and to make the installation
go a bit smoother.  You should remove them before moving into a
production environment.

Remove anonymous users? [Y/n] y
 ... Success!

Normally, root should only be allowed to connect from 'localhost'.  This
ensures that someone cannot guess at the root password from the network.

Disallow root login remotely? [Y/n] y
 ... Success!

By default, MariaDB comes with a database named 'test' that anyone can
access.  This is also intended only for testing, and should be removed
before moving into a production environment.

Remove test database and access to it? [Y/n] y
 - Dropping test database...
 ... Success!
 - Removing privileges on test database...
 ... Success!

Reloading the privilege tables will ensure that all changes made so far
will take effect immediately.

Reload privilege tables now? [Y/n] y
 ... Success!

Cleaning up...

All done!  If you've completed all of the above steps, your MariaDB
installation should now be secure.

Thanks for using MariaDB!

6、選用合適的配置文件

MariaDB會給我們提供示例配置文件，根據機器內存進行選擇，稍作修改即可使用。

# ls /usr/share/mysql/my-*
/usr/share/mysql/my-huge.cnf             /usr/share/mysql/my-medium.cnf
/usr/share/mysql/my-innodb-heavy-4G.cnf  /usr/share/mysql/my-small.cnf
/usr/share/mysql/my-large.cnf
# cp  /usr/share/mysql/my-huge.cnf /etc/my.cnf
cp: overwrite ‘/etc/my.cnf’? y

重載配置文件

# systemctl reload mysql.service

7、Mysql/MariaDB的管理

 service mysql start
 service mysql restart
 service mysql stop

8、Mysql/MariaDB遠程登錄管理

x:\>mysql -u root -pvmware
mysql> use mysql;
mysql> update user set host = '%' where user = 'root';
mysql> flush privileges;