title: dpkg: error processing package mysql-server (dependency problems)?
body: <p>When I try to install mysql-server, an error comes like:</p>
  
  <pre><code>dpkg: error processing package mysql-server (--configure):
  dependency problems - leaving unconfigured
  Errors were encountered while processing:
   mysql-server-5.7
   mysql-server
  E: Sub-process /usr/bin/dpkg returned an error code (1)
  </code></pre>
  
  <p>What does it mean. Any ideas?</p>