提示：以下操作均在root权限下进行。

# 查看有没有安装MySQL：

dpkg -l | grep mysql

# 安装MySQL：

apt install mysql-server

安装完成之后可以使用如下命令来检查是否安装成功：

netstat -tap | grep mysql

通过上述命令检查之后，如果看到有 mysql 的socket处于 LISTEN 状态则表示安装成功。

登录mysql数据库可以通过如下命令：

mysql -u root -p

-u 表示选择登陆的用户名， -p 表示登陆的用户密码，现在是mysql数据库是没有密码的，Enter password:处直接回车，就能够进入mysql数据库。

然后通过 show databases; 就可以查看当前的所有数据库。

接下来，为了确保数据库的安全性和正常运转，对数据库进行初始化操作。这个初始化操作涉及下面5个步骤。

（1）安装验证密码插件。

（2）设置root管理员在数据库中的专有密码。

（3）随后删除匿名账户，并使用root管理员从远程登录数据库，以确保数据库上运行的业务的安全性。

（4）删除默认的测试数据库，取消测试数据库的一系列访问权限。

（5）刷新授权列表，让初始化的设定立即生效。

对于上述数据库初始化的操作步骤，在下面的输出信息旁边我做了简单注释。

root@ubuntu-virtual-machine:~# mysql_secure_installation

Securing the MySQL server deployment.

Connecting to MySQL using a blank password.

VALIDATE PASSWORD PLUGIN can be used to test passwords
and improve security. It checks the strength of password
and allows the users to set only those passwords which are
secure enough. Would you like to setup VALIDATE PASSWORD plugin? #要安装验证密码插件吗?

Press y|Y for Yes, any other key for No: N # 这里我选择N
Please set the password for root here.

New password: #输入要为root管理员设置的数据库密码

Re-enter new password: #再次输入密码

By default, a MySQL installation has an anonymous user,
allowing anyone to log into MySQL without having to have
a user account created for them. This is intended only for
testing, and to make the installation go a bit smoother.
You should remove them before moving into a production
environment.

Remove anonymous users? (Press y|Y for Yes, any other key for No) : y #删除匿名账户
Success.

Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network.

Disallow root login remotely? (Press y|Y for Yes, any other key for No) : N #禁止root管理员从远程登录，这里我没有禁止

... skipping.
By default, MySQL comes with a database named 'test' that
anyone can access. This is also intended only for testing,
and should be removed before moving into a production
environment.

Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y #删除test数据库并取消对它的访问权限