Returning inner hits in results

In Elasticsearch, via nested and child documents, we can have complex data models. Elasticsearch, by default, returns only documents that match the searched type and not the nested/children one that matches the query.

The inner_hits function is introduced in Elasticsearch 5.x to provide this functionality.

Getting ready

You will need an up-and-running Elasticsearch installation as used in the Downloading and installing Elasticsearch recipe in Chapter 2, Downloading and Setup.

To execute curl via a command line, you need to install curl for your operating system.

To correctly execute the following commands, you will need an index populated with the chapter_05/populate_query.sh script available in the online code.

How to do it...

To return inner hits during a query, we will perform the following steps:

1. From the command line, we can execute a call adding inner_hits as follows:

           curl -XPOST 'http://127.0.0.1:9200/test-index/test-
           type/_search?pretty...