title: Why does "select count(*)" from nothing return 1
body: <p>With SQL Server 2012 :</p>
  
  <pre><code>use master
  select *
  </code></pre>
  
  <p>yields </p>
  
  <blockquote>
    <p>Must specify table to select from</p>
  </blockquote>
  
  <p>which is exactly what I would expect. </p>
  
  <p>But the funny thing is that</p>
  
  <pre><code>use master
  select count(*)
  </code></pre>
  
  <p>returns 1. </p>
  
  <p>Can someone explain to me what is counted here?</p>
  
  <p>Edit : And possibly include sources...</p>