linux系统是centos7.x.x版本，mysql5.7.x（这里介绍的是rpm安装方式，操作步骤较为简单，容易接受）
1.首先将系统自带的mariadb-lib卸载，不然后续安装时会报以下错误：
# error: mariadb-libs is obsoleted by mysql-community-libs-5.7.28-1.el7.x86_64
# error: Failed dependencies:
# error: libaio.so.1()(64bit) is needed by mysql-community-server-5.7.28-1.el7.x86_64
# error: libaio.so.1(LIBAIO_0.1)(64bit) is needed by mysql-community-server-5.7.28-1.el7.x86_64
# error: libaio.so.1(LIBAIO_0.4)(64bit) is needed by mysql-community-server-5.7.28-1.el7.x86_64
查看系统marialdb-lib版本，rpm -qa | grep -i mariadb（我服务器查到的是 mariadb-libs-5.5.52-1.el7.x86_64），然后执行卸载：rpm -e –nodeps mariadb-libs-5.5.52-1.el7.x86_64
2.安装最新的libaio
yum install libaio
yum install net-tools
3.下载并安装mysql
wget http://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-5.7.28-1.el7.x86_64.rpm-bundle.tar
tar -xvf mysql-5.7.28-1.el7.x86_64.rpm-bundle.tar
通常安装下面这四个文件即可
rpm -ivh mysql-community-common-5.7.28-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-5.7.28-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-5.7.28-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-5.7.28-1.el7.x86_64.rpm
如果出现以下错误（需安装：yum install numactl），或是安装以上包时追加 –nodeps –force（rpm -ivh mysql-community-common-5.7.28-1.el7.x86_64.rpm –nodeps –force）：
warning: mysql-community-server-5.7.28-1.el7.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
error: Failed dependencies:
libnuma.so.1()(64bit) is needed by mysql-community-server-5.7.28-1.el7.x86_64
libnuma.so.1(libnuma_1.1)(64bit) is needed by mysql-community-server-5.7.28-1.el7.x86_64
libnuma.so.1(libnuma_1.2)(64bit) is needed by mysql-community-server-5.7.28-1.el7.x86_64
4. 初始化
为了保证数据库目录为与文件的所有者为 mysql 登陆用户，如果你的linux系统是以 root 身份运行 mysql 服务，需要执行下面的命令初始化
mysqld –initialize –user=mysql
my.cnf/my.ini 支持Emoji表情
character-set-server=utf8mb4
collation_server=utf8mb4_unicode_ci
cat /var/log/mysqld.log | grep password（查看初始密码），找到 “root@localhost:xxx”
5.启动，修改默认密码
启动：
systemctl start mysqld
或 service mysqld start
停止：
service mysqld stop
重启：
service mysqld restart
连接mysql
mysql -u root -p
修改密码（不然后续操作会提示请更换密码）
set password = password[‘xxx’] // xxx处替换为你要设置的新密码，看好，说的是只替换xxx
6. 仅上述操作，只能当前服务器内登录连接，相信你肯定是要外部开发调试连接的，那么，下一条命令是配置外部访问权限：
grant all privileges on *.* to ‘root’ @’%’ identified by ‘xxx’; // xxx处替换为外部访问密码，可区别于本地密码，方便后期管理，
flush privileges;
如果转载，请注明出处：
https://blog.csdn.net/hz_hero/article/details/81157024