title: How to get last record
body: <p>I need to get last record from db. I'm using sqlalchemy.
  At the moment, I'm doing like that:</p>
  <pre><code>obj = ObjectRes.query.all()
  return str(obj[-1].id)
  </code></pre>
  <p>But it's too heavy query. How can I get last record better?</p>