安装包方式安装mysql数据库
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-5.7.25-linux-glibc2.12-x86_64.tar.gz版本
rpm -qa | grep -i mysql 查看安装的MySQL
yum remove mysql-community-server-5.6.36-2.el7.x86_64 用这个将安装的MySQL全部卸载了
卸载到rpm -qa | grep -i mysql 查找不到任何关于MySQL的东西
rpm -qa | grep mariadb 查看安装的mariadb
rpm -e --nodeps mariadb-libs-5.5.56-2.el7.x86_64 用这个将安装的mariadb 全部卸载了
卸载到rpm -qa | grep mariadb 查找不到任何关于mariadb 的东西
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
进入目录
cd /opt/mysql
解压安装包
tar -zxvf mysql-5.7.25-linux-glibc2.12-x86_64.tar.gz
重命名
mv mysql-5.7.25-linux-glibc2.12-x86_64 mysql-5.7.25
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 如无创建
cat /etc/passwd | grep mysql 如无创建
如无，执行添加命令：
groupadd mysql
useradd -r -g mysql mysql
安装数据库
创建data目录
cd mysql-5.7.25
mkdir data
将/opt/mysql/mysql-5.7.25的所有者及所属组改为mysql
chown -R mysql.mysql /opt/mysql/mysql-5.7.25
在/opt/mysql/mysql-5.7.25/support-files目录下创建my_default.cnf
cd /opt/mysql/mysql-5.7.25/support-files
vim my_default.cnf
（以下内容是my_default.cnf内容）------------------------------------------------
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 = /opt/mysql/mysql-5.7.25
datadir = /opt/mysql/mysql-5.7.25/data
port = 3306
socket = /tmp/mysql.sock
character-set-server=utf8
log-error = /opt/mysql/mysql-5.7.25/data/mysqld.log
pid-file = /opt/mysql/mysql-5.7.25/data/mysqld.pid
（以上内容是my_default.cnf内容）------------------------------------------------------
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 /opt/mysql/mysql-5.7.25
./bin/mysqld --initialize --user=mysql --basedir=/opt/mysql/mysql-5.7.25/ --datadir=/opt/mysql/mysql-5.7.25/data/
初始化完成之后，查看日志
/opt/mysql/mysql-5.7.25/data/mysqld.log
（找到临时密码在最后 [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 /opt/mysql/mysql-5.7.25
./bin/mysql -u root -p
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;
重启mysql生效
service mysql stop 关闭mysql
service mysql start 开启mysql
service mysql restart 重启mysql
