注意：

从 CentOS 7 系统开始，MariaDB 成为 yum 源中默认的数据库安装包。在 CentOS 7 及以上的系统中使用 yum 安装 MySQL 包将无法使用 MySQL。可以选择使用完全兼容的 MariaDB

下载、安装RPM源

官方下载地址 https://dev.mysql.com/downloads/repo/yum/
因为系统是CentOS7 所以选择 Red Hat Enterprise Linux 7 / Oracle Linux 7 (Architecture Independent), RPM Package
点 “Download”
转跳到下载页面，右键“No thanks, just start my download.”复制链接地址
目前最新的是这 https://dev.mysql.com/get/mysql80-community-release-el7-1.noarch.rpm

wget https://dev.mysql.com/get/mysql80-community-release-el7-1.noarch.rpm
rpm -ivh mysql80-community-release-el7-1.noarch
yum makecache

设置所需的MySQL安装版本

查看当前可安装版本

[root@localhost ~]# yum repolist all | grep mysql
mysql-cluster-7.5-community/x86_64 MySQL Cluster 7.5 Community   disabled
mysql-cluster-7.5-community-source MySQL Cluster 7.5 Community - disabled
mysql-cluster-7.6-community/x86_64 MySQL Cluster 7.6 Community   disabled
mysql-cluster-7.6-community-source MySQL Cluster 7.6 Community - disabled
mysql-connectors-community/x86_64  MySQL Connectors Community    enabled:     74
mysql-connectors-community-source  MySQL Connectors Community -  disabled
mysql-tools-community/x86_64       MySQL Tools Community         enabled:     74
mysql-tools-community-source       MySQL Tools Community - Sourc disabled
mysql-tools-preview/x86_64         MySQL Tools Preview           disabled
mysql-tools-preview-source         MySQL Tools Preview - Source  disabled
mysql55-community/x86_64           MySQL 5.5 Community Server    disabled
mysql55-community-source           MySQL 5.5 Community Server -  disabled
mysql56-community/x86_64           MySQL 5.6 Community Server    disabled
mysql56-community-source           MySQL 5.6 Community Server -  disabled
mysql57-community/x86_64           MySQL 5.7 Community Server    disabled
mysql57-community-source           MySQL 5.7 Community Server -  disabled
mysql80-community/x86_64           MySQL 8.0 Community Server    enabled:     49
mysql80-community-source           MySQL 8.0 Community Server -  disabled

当前默认的为mysql8.0
接下来修改安装版本,我将要安装的是MySQL5.5

yum -y install yum-utils
yum-config-manager --disable mysql80-community
yum-config-manager --enable mysql55-community

验证确认

yum repolist all | grep mysql

查看当前enable的版本

[root@localhost ~]# yum repolist all | grep mysql
mysql-cluster-7.5-community/x86_64 MySQL Cluster 7.5 Community   disabled
mysql-cluster-7.5-community-source MySQL Cluster 7.5 Community - disabled
mysql-cluster-7.6-community/x86_64 MySQL Cluster 7.6 Community   disabled
mysql-cluster-7.6-community-source MySQL Cluster 7.6 Community - disabled
mysql-connectors-community/x86_64  MySQL Connectors Community    enabled:     74
mysql-connectors-community-source  MySQL Connectors Community -  disabled
mysql-tools-community/x86_64       MySQL Tools Community         enabled:     74
mysql-tools-community-source       MySQL Tools Community - Sourc disabled
mysql-tools-preview/x86_64         MySQL Tools Preview           disabled
mysql-tools-preview-source         MySQL Tools Preview - Source  disabled
mysql55-community/x86_64           MySQL 5.5 Community Server    enabled:    427
mysql55-community-source           MySQL 5.5 Community Server -  disabled
mysql56-community/x86_64           MySQL 5.6 Community Server    disabled
mysql56-community-source           MySQL 5.6 Community Server -  disabled
mysql57-community/x86_64           MySQL 5.7 Community Server    disabled
mysql57-community-source           MySQL 5.7 Community Server -  disabled
mysql80-community/x86_64           MySQL 8.0 Community Server    disabled
mysql80-community-source           MySQL 8.0 Community Server -  disabled

安装数据库

安装MySQL

yum install mysql-community-server

安装MySQL 扩展

yum -y install mysql-connector-odbc mysql-devel libdbi-dbd-mysql

初始化配置

启动数据库

systemctl start mysqld.service
mysqladmin -u root password "passw0rd" #设置MySQL数据库root密码
[root@localhost ~]# mysql -u root -p #登陆数据库
Enter password:
DROP DATABASE test; #删除test 数据库
DELETE FROM mysql.user WHERE user = ""; #删除匿名账号
FLUSH PRIVILEGES; #刷新权限
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'passw0rd' WITH GRANT OPTION; #开启数据库root 账号外网访问

编码修改,中文注释部分为新增字段,该配置文件MySQL5.5 测试通过

vi /etc/my.cnf

# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.5/en/server-configuration-defaults.html

[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
character-set-server=utf8 #默认编码修改改

# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

# Recommended in standard MySQL setup
#sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES

[client]
default-character-set=utf8 #默认编码修改

[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

重启数据库并验证

systemctl restart mysqld.service
[root@localhost ~]# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.5.62 MySQL Community Server (GPL)

Copyright (c) 2000, 2018, 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 variables like '%char%';
+--------------------------+----------------------------+
| Variable_name            | Value                      |
+--------------------------+----------------------------+
| character_set_client     | utf8                       |
| character_set_connection | utf8                       |
| character_set_database   | utf8                       |
| character_set_filesystem | binary                     |
| character_set_results    | utf8                       |
| character_set_server     | utf8                       |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+--------------------------+----------------------------+
8 rows in set (0.01 sec)

设置开机启动

systemctl enable mysqld.service

小明の博客

CentOS7 RPM 安装 MySQL

注意：