本节主要介绍在CentOS7下安装配置Mariadb数据库的步骤。
1、在CentOS 7下使用yum命令安装mariadb数据库及其依赖：
yum install mariadb*
小注：这里加*主要是安装mariadb其他相关的包，例如客户端连接包，按照后，可在本地直接连接server
2、启动mariadb数据库：
systemctl start mariadb
3、验证启动状态：
systemctl status mariadb
● mariadb.service - MariaDB database server
Loaded: loaded (/usr/lib/systemd/system/mariadb.service; disabled; vendor preset: disabled)
Active: active (running) since Thu 2017-11-16 10:43:29 CST; 4s ago
Process: 21750 ExecStartPost=/usr/libexec/mariadb-wait-ready $MAINPID (code=exited, status=0/SUCCESS)
Process: 21718 ExecStartPre=/usr/libexec/mariadb-prepare-db-dir %n (code=exited, status=0/SUCCESS)
Main PID: 21749 (mysqld_safe)
CGroup: /system.slice/mariadb.service
├─21749 /bin/sh /usr/bin/mysqld_safe --basedir=/usr
└─21927 /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --log-error=/var/log/mariadb/mariad...
Nov 16 10:43:27 izm5e4ame76454x0an58p4z systemd[1]: Starting MariaDB database server...
Nov 16 10:43:27 izm5e4ame76454x0an58p4z mariadb-prepare-db-dir[21718]: Database MariaDB is probably initialized in /var/lib/mysql already, nothin... done.
Nov 16 10:43:27 izm5e4ame76454x0an58p4z mariadb-prepare-db-dir[21718]: If this is not the case, make sure the /var/lib/mysql is empty before runn...b-dir.
Nov 16 10:43:27 izm5e4ame76454x0an58p4z mysqld_safe[21749]: 171116 10:43:27 mysqld_safe Logging to '/var/log/mariadb/mariadb.log'.
Nov 16 10:43:28 izm5e4ame76454x0an58p4z mysqld_safe[21749]: 171116 10:43:28 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
Nov 16 10:43:29 izm5e4ame76454x0an58p4z systemd[1]: Started MariaDB database server.
Hint: Some lines were ellipsized, use -l to show in full.
当出现类似如上提示，表示mysql已经启动成功。如果在验证过程中出现错误，请查看/var/log/mariadb/mariadb.log文件（默认日志文件），查看启动失败的原因。
4、设置服务开机自动启动
systemctl enable mariadb
Created symlink from /etc/systemd/system/multi-user.target.wants/mariadb.service to usr/lib/systemd/system/mariadb.service.
5、初始化MariaDB
```[root@izm5e4ame76454x0an58p4z conf]# 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):初次运行直接回车
Setting the root password ensures that nobody can log into the MariaDB
`root user without the proper authorisation.
`
Set root password? [Y/n]在这里输入Y
New password:请在此输入需要设置的root的密码
Re-enter new password:请在此再次输入需要设置的root的密码
Remove anonymous users? [Y/n]<– 是否删除匿名用户，回车
Disallow root login remotely? [Y/n]<–是否禁止root远程登录,回车,
Remove test database and access to it? [Y/n]<– 是否删除test数据库，回车
Reload privilege tables now? [Y/n]<– 是否重新加载权限表，回车
6、登录验证
mysql -uroot -p
输入刚才设置的密码，登录，如果登录成功，表示初始化工作已经完成。
1、修改my.cnf文件：
vim /etc/my.cnf在[mysqld]标签下添加
init_connect=SET collation_connection = utf8_unicode_ci'
init_connect='SET NAMES utf8'
character-set-server=utf8
collation-server=utf8_unicode_ci
skip-character-set-client-handshake
2、修改/etc/my.cnf.d/client.cnf文件：
vim /etc/my.cnf.d/client.cnf
在[client]中添加
default-character-set=utf8
3、修改/etc/my.cnf.d/mysql-clients.cnf文件：
vim
/etc/my.cnf.d/mysql-clients.cnf
在[mysql]中添加
default-character-set=utf8
4、配置完后，重启mariadb：
systemctl restart mariadb
5、进入MariaDB查看字符集
mysql
> show variables like "%character%";
> show variables like "%collation%";
字符集配置完成。
小坑1：执行命令提示：Ignoring query to other database
原因：连接时，没有使用-u参数
登录mysql后，创建用户并授权：
grant all privileges on *.* to sonar@'%' identified by 'yocRLLCl';
重新加载配置：
flush privileges;
用新账号重新登录，验证结果：
mysql -usonar -p