Using exists and missing filters

One of the main characteristics of ElasticSearch is schemaless storage. So due to its schemaless nature two kinds of filters are required to check if a field exists in a document (the exists filter) or if it is missing (the missing filter).

Getting ready

You need a working ElasticSearch cluster and the data populated with the populate script.

How to do it...

For executing existing and missing filters, we need to perform the following steps:

1. To search all the test-type documents that have a field called parsedtext the query will be as follows:

   curl -XPOST 'http://127.0.0.1:9200/test-index/test-type/_search' -d '{
       "query": {
           "filtered": {
               "filter": {
                   "exists": {
                       "field":"parsedtext"
                   }
               },
               "query": {
                   "match_all": {}
               }
           }
       }
   }'

2. To search all the test-type documents that do not have a field called parsedtext, the query will be as follows...