title: SQL convert "left join" with a "from" clause with multiple tables and a "where" condition
body: <p>Image you have 2 tables like this:</p>
  
  <p><strong>User</strong>: with columns ID, NAME and APPARTMENT_ID.</p>
  
  <p><strong>Appartment</strong>: with columns ID, ADDRESS.</p>
  
  <p>user.appartment_id is a <strong>foreign key</strong> for appartment.id.</p>
  
  <p>With a <strong>left join</strong> I can do something like:</p>
  
  <pre><code>select u.name, a.address from user as u 
      left join appartment as a on u.appartment_id = a.id
  </code></pre>
  
  <p>And users with appartment_id null will match. If i write a select with this other structure (without using left join) those users won't match.</p>
  
  <pre><code>selct u.name, a.address from user as u, appartment as a
  where u.appartment_id = a.id
  </code></pre>
  
  <p>Is there a way to modify the second query in order to obtain the same result set of the first, but without using left join?</p>
  
  <p>Thanks</p>