title: not showing DISTINCT record on 3 table join
body: <p>I try following query for display DISTINCT record from 3 table.But there also display repeat user record.</p>
  
  <pre><code>SELECT DISTINCT users.sid, users.username, users.registration_date, users.FirstName,
      users.LastName, users.phoneNumber, listings.Resume, uploaded_files.saved_file_name
  FROM users JOIN listings
  ON users.sid = listings.user_sid
  JOIN uploaded_files
  ON listings.Resume=uploaded_files.id
  WHERE listings.listing_type_sid = '7' AND listings.Resume != 'NULL'
  </code></pre>