title: max(date) sql query in laravel 5.2
body: <p>I just wonder how to use below MySQL query in laravel5.2 using eloquent.</p>
  
  <pre><code>SELECT MAX(date) AS "Last seen date" FROM instances WHERE ad_id =1
  </code></pre>
  
  <p>I have column date in instance table .</p>
  
  <p>I would like to select the latest date from that table where ad_id =1</p>