title: How to return and search by dynamic fields in DSE Search
body: <p>I have a simple Cassandra KF:</p>
  
  <pre><code>create table messages (
    id varchar,
    headers map&lt;varchar, varchar&gt;,
    primary key (id));
  </code></pre>
  
  <p>The table gets an auto-generated Solr index. The values of the <code>headers</code> field will be around what you expect in email headers. I can see that Solr generates the following line for the headers:</p>
  
  <pre><code>&lt;dynamicField indexed="true" multiValued="false" name="headers*" stored="true" type="TextField"/&gt;
  </code></pre>
  
  <p>However, I can't see to find anything in the headers, nor get their values using Solr API. A record:</p>
  
  <pre><code>cassandra@cqlsh:tpb&gt; SELECT id, headers FROM messages;
  
  1492cc10-046d-11e6-a332-55ae2575ea1a | {'component-count': '1', 'component-type-0': 'Document-Upload', 'consumer-behalf': 'true', 'date': 'Sun Apr 17 2016 00:22:02 GMT-0700 (PDT)', 'from': '718bcc80-9def-11e5-a837-0800200c9a66@1a4de124-5761-4668-9e9d-a880aa4e6dd1', 'message-id': '1492cc10-046d-11e6-a332-55ae2575ea1a@32d2a682-af07-4108-a15a-de6f8a75e811', 'to': '"mark-watney@cool-dude"@32d2a682-af07-4108-a15a-de6f8a75e811', 'transaction-id': '14585b20-046d-11e6-a332-55ae2575ea1a'}
  </code></pre>
  
  <p>Running these two queries don't ever return me any header values (note that any URL encoding is reversed for readability):</p>
  
  <pre><code>...select?q=id:1492cc10-046d-11e6-a332-55ae2575ea1a&amp;fl=id,headersconsumer-behalf&amp;wt=json&amp;indent=true
  ...select?q=id:1492cc10-046d-11e6-a332-55ae2575ea1a&amp;fl=id,headers*&amp;wt=json&amp;indent=true
  </code></pre>
  
  <p>Searching by header value seems to yield no results either, e.g.</p>
  
  <p>...select?q=headersdate:Sun&amp;fl=id&amp;wt=json&amp;indent=true
  ...select?q=headersconsumer-behalf:true&amp;fl=id&amp;wt=json&amp;indent=true</p>
  
  <p>both return empty sets (but should match the above document).</p>
  
  <p>It feels like I'm missing something, but I can't figure out what. Solr admin reports "headers*" field to exist, and be properly indexed and what not.</p>
  
  <p>So, the question: how can I return and search by dynamic fields (inferred from a Cassandra map) in DSE?</p>