title: Is it possible to get contents of copy_to field in Elasticsearch?
body: <p>I'm using Elasticsearch v2.3.0. Suppose I have an index with mapping:</p>
  
  <pre><code>{
  "mappings": {
    "post": {
      "dynamic": false,
      "_source": {
        "enabled": true
      },
      "properties": {
        "text": {
          "norms": {
            "enabled": false
          },
          "fielddata": {
            "format": "disabled"
          },
          "analyzer": "text_analyzer",
          "type": "string"
        },
        "subfield": {
          "properties": {
            "subsubfield": {
              "properties": {
                "subtext": {
                  "index": "no",
                  "analyzer": "text_analyzer",
                  "type": "string",
                  "copy_to": "text"
                }
              }  
            }
          }
        }
      },
      "_all": {
        "enabled": false
      }
    }
  }
  </code></pre>
  
  <p>So, text from <code>subfield.subsubfield.subtext</code> is copied to text <code>field</code> due to <code>copy_to</code>. If you query a post, then only data from <code>text</code> is shown in <code>text</code> field, because <code>_source</code> is not modified. If you want to obtain all text, you should aggregate all fields on client. This can be inconvenient if there are many subfields. </p>
  
  <p>Is there a magic query, which allows to get <code>text</code> field with all text copied to it?</p>