一、下载
进入到mysql官网下载自己对应版本的mysql，
下载地址：https://dev.mysql.com/downloads/mysql/5.7.html#downloads
我这里下载mysql-5.7.31-linux-glibc2.12-x86_64.tar.gz版本
也可以进入linux后用命令下载
wget https://cdn.mysql.com//Downloads/MySQL-5.7/mysql-5.7.31-linux-glibc2.12-x86_64.tar.gz二、环境配置
安装前，我们可以检测系统是否自带安装 MySQL:
rpm -qa | grep mysql如有，类似
mysql-libs-5.1.52-1.el6_0.1.x86_64那可以选择进行卸载:
rpm -e mysql-libs-5.1.52-1.el6_0.1.x86_64 // 普通删除模式
rpm -e --nodeps mysql-libs-5.1.52-1.el6_0.1.x86_64 // 强力删除模式，如果使用上面命令删除时，提示有依赖的其它文件，则用该命令可以对其进行强力删除检查否存在 mariadb 数据库，如有，卸载之，卸载同上
rpm -qa | grep mariadb如有，类似
mariadb-libs-5.5.56-2.el7.x86_64则 卸载
rpm -e --nodeps mariadb-libs-5.5.56-2.el7.x86_64用WinSCP 5.14.4工具将下载的mysql-5.7.25-linux-glibc2.12-x86_64.tar.gz上传到linux服务器的/opt/mysql目录下面
三、安装
tar -zxvf mysql-5.7.31-linux-glibc2.12-x86_64.tar.gz -C ../servers/重命名
mv mysql-5.7.31-linux-glibc2.12-x86_64 mysql-5.7.31添加系统mysql组和mysql用户
检查mysql组和用户是否存在，如无创建
cat /etc/group | grep mysql
#类似
mysql:x:490:
cat /etc/passwd | grep mysql
#类似
mysql:x:496:490::/home/mysql:/bin/bash以上为存在的情况，如无，执行添加命令：
groupadd mysql
useradd -r -g mysql mysql
#useradd -r参数表示mysql用户是系统用户，不可用于登录系统安装数据库
创建data目录
cd mysql-5.7.31
mkdir data将/opt/mysql/mysql-5.7.31的所有者及所属组改为mysql
chown -R mysql:mysql /export/servers/mysql-5.7.31在/export/servers/mysql-5.7.31/support-files目录下创建my_default.cnf
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html
# *** DO NOT EDIT THIS FILE. It's a template which will be copied to the
# *** default location during install, and will be replaced if you
# *** upgrade to a newer version of MySQL.
[mysqld]
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
basedir = /export/servers/mysql-5.7.31
datadir = /export/servers/mysql-5.7.31/data
port = 3306
socket = /tmp/mysql.sock
character-set-server=utf8
log-error = /export/servers/mysql-5.7.31/data/mysqld.log
pid-file = /export/servers/mysql-5.7.31/data/mysqld.pid拷贝，如果提示是否覆盖，y
cp support-files/my_default.cnf /etc/my.cnf初始化 mysqld
cd /export/servers/mysql-5.7.31
./bin/mysqld --initialize --user=mysql --basedir=/export/servers/mysql-5.7.31 --datadir=/export/servers/mysql-5.7.31/data/初始化完成之后，查看日志
/export/servers/mysql-5.7.31/data/mysqld.log临时密码
2019-04-08T06:14:29.790033Z 1 [Note] A temporary password is generated for root@localhost: a8?DQir=T+k+把启动脚本放到开机初始化目录
cp support-files/mysql.server /etc/init.d/mysql启动mysql服务
service mysql start登录mysql，密码为初始密码
cd /export/servers/mysql-5.7.31
./bin/mysql -u root -p2020-09-23T09:29:18.970981Z 1 [Note] A temporary password is generated for root@localhost: .L6og)3HPuu1修改密码
mysql> set password=password('123456');
mysql> grant all privileges on *.* to root@'%' identified by '123456';
mysql> flush privileges;添加远程访问权限
mysql> use mysql;
mysql> update user set host='%' where user = 'root';
mysql> flush privileges;这里可能会出现这个错误
ERROR 1062 (23000): Duplicate entry '%-root' for key 'PRIMARY'
如果执行update语句时出现ERROR 1062 (23000): Duplicate entry '%-root' for key 'PRIMARY' 错误，说明有多个ROOT用户纪录在USER表中了.
需要select host from user where user = 'root';
查看一下host是否已经有了%这个值，有了就可以了.
重启mysql生效
service mysql stop
service mysql start或
service mysql restart