CentOS环境下安装MYSQL

下载并安装MySQL官方的 Yum Repository

1. 安装Yum Repository

 wget -i -c http://dev.mysql.com/get/mysql57-community-release-el7-10.noarch.rpm

2. 下载MySQL服务器

yum -y install mysql57-community-release-el7-10.noarch.rpm

3. 安装MySQL服务器

yum -y install mysql-community-server

MySQL数据库的设置

1. 启动MySQL

 systemctl start  mysqld.service

2. 查看MySQL运行状态

systemctl status mysqld.service

3. 获取MySQL临时密码

grep 'temporary password' /var/log/mysqld.log

4. 登录并修改密码

mysql -uroot -p			回车输入刚刚获取的密码

ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';

5. 授予权限给其他机器登录

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

FLUSH  PRIVILEGES;

更改密码时报错ERROR 1819 (HY000): Your password does not satisfy the current policy requirements

原因：MySQL有密码设置的规范，具体是与validate_password_policy的值有关。

其中密码的长度是由validate_password_length决定的，而validate_password_length的计算公式是

validate_password_length = validate_password_number_count + validate_password_special_char_count + (2 * validate_password_mixed_case_count)
输入命令：

set global validate_password_policy=0;

set global validate_password_length=1;

再次使用ALTER USER ‘root’@‘localhost’ IDENTIFIED BY ‘123456’;更改密码

安装Yum Repository之后，以后每次yum操作都会自动更新，可以卸载掉：

yum -y remove mysql57-community-release-el7-10.noarch