$wget https://dev.mysql.com/get/mysql80-community-release-el7-2.noarch.rpm
$sudo rpm -Uvh mysql80-community-release-el7-2.noarch.rpm

#查看MySQL数据库各个版本信息
$yum repolist all | grep mysql

# Enable to use MySQL 5.6
[mysql56-community]
name=MySQL 5.6 Community Server
baseurl=http://repo.mysql.com/yum/mysql-5.6-community/el/7/$basearch/
enabled=0 # 禁止
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql

# Enable to use MySQL 5.7
[mysql57-community]
name=MySQL 5.7 Community Server
baseurl=http://repo.mysql.com/yum/mysql-5.7-community/el/7/$basearch/
enabled=1 # 安装
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql

[mysql80-community]
name=MySQL 8.0 Community Server
baseurl=http://repo.mysql.com/yum/mysql-8.0-community/el/7/$basearch/
enabled=0 # 禁止
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql

#执行以下命令安装MySQL
yum install mysql-community-server
#启动mysql（CentOS7中）
systemctl start mysqld.service
#低版本的操作系统可用以下指令
service mysqld start
#查看MySQL状态
systemctl status mysqld.service
#低版本操作系统可用以下指令
service mysqld status

$grep "password" /var/log/mysqld.log
2019-04-11T08:17:16.706096Z 1 [Note] A temporary password is generated for root@localhost: ux#bkaM(k1q-
$mysql -u root -p
>ux#bkaM(k1q-

# 修改密码
mysql>ALTER USER 'root'@'localhost' IDENTIFIED BY 'complex password';
mysql>set global validate_password_policy=0;
mysql>set global validate_password_length=1;
mysql>ALTER USER 'root'@'localhost' IDENTIFIED BY 'simple password';

mysql>GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'password' WITH GRANT OPTION;

mysql>GRANT ALL PRIVILEGES ON *.* TO 'jack'@’10.10.50.127’ IDENTIFIED BY 'password' WITH GRANT OPTION;