title: Laravel - Get records collection, if not exists in another table
body: <p>I need to get all records from table IF these records not exists in another table, e.g.<br>
  <strong>Table 'Cars'</strong>  </p>
  
  <pre><code>| ID | Name_of_car  
  +----+----------------  
  | 1 .| Toyota  
  +----+----------------  
  | 2 .| Ford
  </code></pre>
  
  <p><strong>Table 'Crashed_cars'</strong>  </p>
  
  <pre><code>| car_id | crash_date  
  +--------+----------------  
  | 1 .....| 22-02-2016  
  </code></pre>
  
  <p>Now I want to get all not crashed cars - how can I do this?<br>
  At the moment I use a loop, but due to the number of entries (about 3000) I would have to use the direct collection. Here is my query:  </p>
  
  <pre><code>Cars::select( 'id', 'firstname', 'lastname', 'car', 'color' )-&gt;get();
  </code></pre>