centos7 mysql数据库安装和配置

Posted 2021-02-08

一、系统环境

[[email protected] ~]# cat /etc/redhat-release
CentOS Linux release 7.6.1810 (Core)

二、mysql安装

#yum install mysql mysql-server mysql-devel
安装mysql-server失败，如下图：

[[email protected] ~]# 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

这是因为CentOS 7用mariadb代替了MySQL数据库软件。

---

有两种解决办法：

1、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授权许可。开发这个分支的原因之一是：甲骨文公司收购了MySQL后，有将MySQL闭源的潜在风险，因此社区采用分支的方式来避开这个风险。MariaDB的目的是完全兼容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。

[[email protected] ~]# yum install mariadb-server mariadb
mariadb数据库的相关命令是：

systemctl start mariadb #启动MariaDB

systemctl stop mariadb #停止MariaDB

systemctl restart mariadb #重启MariaDB

systemctl enable mariadb #设置开机启动

所以先启动数据库

[[email protected] ~]# systemctl start mariadb
然后就可以正常使用mysql了

[[email protected] ~]# 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。

2、方法二：官网下载安装mysql-server
下载mysql：
wget http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpm
源码安装：
rpm -ivh mysql-community-release-el7-5.noarch.rpm
安装服务：
yum install mysql-community-server
安装成功后重启mysql服务。

service mysqld restart
初次安装mysql，root账户没有密码。

[[email protected] ~]# 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mysql登录密码：

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

mysql>
不需要重启数据库即可生效。

在mysql安装过程中如下内容：

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

所以安装完以后mariadb自动就被替换了，将不再生效。

[[email protected] ~]# rpm -qa |grep mariadb
[[email protected] ~]#

三、配置mysql

1、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。

2、远程连接设置
把在所有数据库的所有表的所有权限赋值给位于所有IP地址的root用户。

mysql> grant all privileges on . to [email protected]‘%‘identified by ‘password‘;
如果是新用户而不是root，则要先新建用户

mysql>create user ‘username‘@‘%‘ identified by ‘password‘;
此时就可以进行远程连接了。