title: Laravel query where subquery
body: <p>I am looking for the best way to perform the query below as a <code>Laravel 4.2</code> <em>query</em>.  I am struggling on the <code>where</code> clause which has a sub <em>query</em> to work.</p>
  
  <p>What my <em>query</em> is doing:
  I have a parent table with a <code>1-many</code> child table.  I want to get a list of all the child records associated to the parent record only knowing a current child record.</p>
  
  <pre><code>select child.id, child.jobNumber
  from child
  where child.parentId = (select child.parentId from child where child.id = 2)
  order by child.jobNumber, child.id
  </code></pre>
  
  <p>Something like:</p>
  
  <pre><code>$query = DB::table('child');
  $query-&gt;select(array('child.id','child.jobNumber'));
  $query-&gt;orderBy('child.jobNumber');
  $query-&gt;orderBy('child.id');
  
  // how do I do my where clause?
  
  $list = $query-&gt;get();
  </code></pre>