title: solr join - return parent and child document
body: <p>I am using Solr's (4.0.0-beta) join capability to query an index that has documents with parent/child relationships.  The join query works great, but I only get the parent documents in the search results.  I believe this is the expected behavior.</p>
  
  <p>Is it possible, though, to get both the parent and the child documents to be returned in the search results? (as separate search hits).</p>
  
  <p>For example:</p>
  
  <p>Parents:</p>
  
  <pre><code>SolrDocument{uid=m_1, media_id=1}&lt;br/&gt;
  SolrDocument{uid=m_2, media_id=2}&lt;br/&gt;
  SolrDocument{uid=m_3, media_id=3}
  </code></pre>
  
  <p>Children:</p>
  
  <pre><code>SolrDocument(uid=p_1, page_id=1, fk_media_id=[1], partNumber=[abc, def, xyz]}&lt;br/&gt;
  SolrDocument(uid=p_2, page_id=2, fk_media_id=[1,2], partNumber=[123, 456]}&lt;br/&gt;
  SolrDocument(uid=p_3, page_id=3, fk_media_id=[1,3], partNumber=[100, 101]}
  </code></pre>
  
  <p>I query by partNumber like this:</p>
  
  <pre><code>{!join from=fk_media_id to=media_id}partNumber:abc
  </code></pre>
  
  <p>and I get the parent document (uid=m_1) in the results, as expected.  But I would like, in this case, both the parent and the child to be returned in the results.  Is that possible?</p>