linux 安装mysql 5.7 1.下载mysql
wget http://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-5.7.12-1.el6.x86_64.rpm-bundle.tar 解压 tar -xf mysql-5.7.12-1.el6.x86_64.rpm-bundle.tar解压完成后由这么几个文件：
mysql-community-client-5.7.12-1.el6.x86_64.rpm mysql-community-common-5.7.12-1.el6.x86_64.rpm mysql-community-devel-5.7.12-1.el6.x86_64.rpm mysql-community-embedded-5.7.12-1.el6.x86_64.rpm mysql-community-embedded-devel-5.7.12-1.el6.x86_64.rpm mysql-community-libs-5.7.12-1.el6.x86_64.rpm mysql-community-libs-compat-5.7.12-1.el6.x86_64.rpm mysql-community-server-5.7.12-1.el6.x86_64.rpm mysql-community-test-5.7.12-1.el6.x86_64.rpm
依次执行安装：
rpm -ivh mysql-community-common-5.7.12-1.el6.x86_64.rpm rpm -ivh mysql-community-server-5.7.12-1.el6.x86_64.rpm ......启动mysql：
/etc/init.d/mysqld start查看mysql目录：
ps aux|grep mysql出现如下：
root 5688 0.0 0.0 113224 3080 pts/0 S 09:35 0:00 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --socket=/var/lib/mysql/mysql.sock --pid-file=/var/run/mysqld/mysqld.pid --basedir=/usr --user=mysql mysql 5886 0.0 2.3 1932112 181040 pts/0 Sl 09:35 0:00 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --user=mysql --log-error=/var/log/mysqld.log --pid-file=/var/run/mysqld/mysqld.pid --socket=/var/lib/mysql/mysql.sock进入mysql安装目录：
cd /var/lib/mysql查看mysql默认密码：
grep "password" /var/log/mysqld.log查找如下语句：A temporary password is generated for root@localhost: fQk2wWh&YRcT 最末尾就是默认初始密码
登录mysql：
/var/lib/mysql/mysql -u root -p重设密码：
SET PASSWORD = PASSWORD('123456');如果有强制密码检查插件，则过简单的密码会提示：Your password does not satisfy the current policy requirements 则需要设置一定强度的强密码，或者启用全局配置，修改密码插件验证规则：
set global validate_password_policy=0; //设置安全级别 set global validate_password_length=6; //默认密码长度为8，可以设置为其它值，最小4位设置新密码:
SET PASSWORD = PASSWORD('123456');赋所有权限：
grant all privileges on *.* to 'root' identified by '123456' with grant option; flush privileges;ok，可以访问了！
