title: TableGateway with multiple FROM tables
body: <p>I would like to do a simple <code>INNER JOIN</code> between two tables in Zend2.</p>
  
  <p>Concretely, I would like to do this in Zend2:</p>
  
  <p><code>SELECT * FROM foo, bar WHERE foo.foreign_id = bar.id;</code></p>
  
  <p>I have a <code>FooTable</code>:</p>
  
  <pre><code>class FooTable
  {
    protected $tableGateway;
  
    public function __construct(TableGateway $tableGateway)
    {
      $this-&gt;tableGateway = $tableGateway;
    }
  
    public function get($id)
    {
      $rowset = $this-&gt;tableGateway-&gt;select(function (Select $select) {
        $select-&gt;from('foo');
      });
    }
  }
  </code></pre>
  
  <p>The <code>$select-&gt;from('foo');</code> returns an error:</p>
  
  <p>==> <strong>Since this object was created with a table and/or schema in the constructor, it is read only.</strong></p>
  
  <p>So, I can't tweak my FROM statement to match a simple inner join between <code>FooTable</code> and <code>BarTable</code>.</p>