centos7 mysql(mariadb)数据库安装和配置

1、系统环境

yum update升级之后的系统版本为

[root@yl-web yl]# cat /etc/redhat-release 
CentOS Linux release 7.1.1503 (Core)

2、mysql安装

通常网上给出的资料都是

#yum install mysql
#yum install mysql-server
#yum install mysql-devel

安装mysql和mysql-devel都成功，可是安装mysql-server失败，以下：

[root@yl-web yl]# yum install mysql-server
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.sina.cn
 * extras: mirrors.sina.cn
 * updates: mirrors.sina.cn
No package mysql-server available.
Error: Nothing to do

查资料发现是CentOS 7 版本将MySQL数据库软件从默认的程序列表中移除，用mariadb代替了。

有两种解决办法：

一、方法一：安装mariadb

MariaDB数据库管理系统是MySQL的一个分支，主要由开源社区在维护，采用GPL受权许可。开发这个分支的缘由之一是：甲骨文公司收购了MySQL后，有将MySQL闭源的潜在风险，所以社区采用分支的方式来避开这个风险。MariaDB的目的是彻底兼容MySQL，包括API和命令行，使之能轻松成为MySQL的代替品。

安装mariadb，大小59 M。

[root@yl-web yl]# yum install mariadb-server mariadb

mariadb数据库的相关命令是：

systemctl start mariadb  #启动MariaDB

systemctl stop mariadb  #中止MariaDB

systemctl restart mariadb  #重启MariaDB

systemctl enable mariadb  #设置开机启动

因此先启动数据库

[root@yl-web yl]# systemctl start mariadb

而后就能够正常使用mysql了

[root@yl-web yl]# mysql -u root -p
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 3
Server version: 5.5.41-MariaDB MariaDB Server

Copyright (c) 2000, 2014, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
4 rows in set (0.00 sec)

MariaDB [(none)]>

安装mariadb后显示的也是 MariaDB [(none)]> ，可能看起来有点不习惯。下面是第二种方法。

二、方法二：官网下载安装mysql-server

# wget http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpm
# rpm -ivh mysql-community-release-el7-5.noarch.rpm
# yum install mysql-community-server

安装成功后重启mysql服务。

# service mysqld restart

初次安装mysql，root帐户没有密码。

[root@yl-web yl]# mysql -u root 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.6.26 MySQL Community Server (GPL)

Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
4 rows in set (0.01 sec)

mysql>

设置密码

mysql> set password for 'root'@'localhost' =password('password');
Query OK, 0 rows affected (0.00 sec)

mysql>

不须要重启数据库便可生效。

在mysql安装过程当中以下内容：

Installed:
  mysql-community-client.x86_64 0:5.6.26-2.el7                mysql-community-devel.x86_64 0:5.6.26-2.el7                
  mysql-community-libs.x86_64 0:5.6.26-2.el7                  mysql-community-server.x86_64 0:5.6.26-2.el7               

Dependency Installed:
  mysql-community-common.x86_64 0:5.6.26-2.el7                                                                            

Replaced:
  mariadb.x86_64 1:5.5.41-2.el7_0          mariadb-devel.x86_64 1:5.5.41-2.el7_0   mariadb-libs.x86_64 1:5.5.41-2.el7_0  
  mariadb-server.x86_64 1:5.5.41-2.el7_0 

因此安装完之后mariadb自动就被替换了，将再也不生效。

[root@yl-web yl]# rpm -qa |grep mariadb
[root@yl-web yl]#

3、配置mysql

一、编码

mysql配置文件为/etc/my.cnf

最后加上编码配置

[mysql]
default-character-set =utf8

这里的字符编码必须和/usr/share/mysql/charsets/Index.xml中一致。

二、远程链接设置

把在全部数据库的全部表的全部权限赋值给位于全部IP地址的root用户。

mysql> grant all privileges on *.* to root@'%'identified by 'password';

若是是新用户而不是root，则要先新建用户

mysql>create user 'username'@'%' identified by 'password';

此时就能够进行远程链接了。