title: Indexing a comma-separated value field in Elastic Search
body: <p>I'm using Nutch to crawl a site and index it into Elastic search. My site has meta-tags, some of them containing comma-separated list of IDs (that I intend to use for search). For example:</p>
  
  <p>contentTypeIds="2,5,15". (note: no square brackets).</p>
  
  <p>When ES indexes this, I can't search for contentTypeIds:5 and find documents whose contentTypeIds <em>contain</em> 5; this query returns only the documents whose contentTypeIds is exactly "5". However, I do want to find documents whose contentTypeIds contain 5. </p>
  
  <p>In Solr, this is solved by setting the contentTypeIds field to multiValued="true" in the schema.xml. I can't find how to do something similar in ES.</p>
  
  <p>I'm new to ES, so I probably missed something.  Thanks for your help!</p>