在安装 Ubuntu 16.04 并设置 lampp 堆栈的过程中。我尝试使用以下代码照常安装 MySQL：
sudo apt-get install mysql-server
但是我从终端得到以下返回：
niall@niall:~$ sudo apt-get install mysql-server
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package mysql-server is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'mysql-server' has no installation candidate
之前在 LTS 中从未遇到过这种情况。