title: Docker instance of MySQL is not setting root password -- any login without a password is allowed
body: <p>I set up a new computer running macOS 10.14.5 and Docker Desktop community 2.0.0.3 (31259) and I noticed that my MySQL container wasn't being created properly.  This is the command that I had run on my previous computer:</p>
  
  <pre><code>docker run --name virtual-mysql -p 3306:3306 -e MYSQL_ROOT_PASSWORD=mypassword -d mysql:5.7.22
  </code></pre>
  
  <p>That worked: it would properly set the root password.  But on the new computer, when I run that command, the root password is NOT set.  I can log in as the root user, but only if I leave the password blank.  Only the root user can create a database.</p>
  
  <p>But more curiously, I can specify ANYTHING as the user, e.g. <code>asdf</code> <em>and successfully log in</em> (!!!).  When I log in as a non-existent user, I can only view the <code>information_schema</code> and I cannot create a database, however -- I get an error: <code>Access denied for user ''@'localhost' to database 'asdf'</code> -- which suggests that perhaps my client isn't sending the login credentials correctly (I am using Sequel Pro 1.1.2 as my MySQL client).</p>
  
  <p>Can someone explain this strange behavior? </p>