ElasticSearch Cookbook - Second Edition

Using a has_child query/filter

ElasticSearch does not only support simple documents, but it also lets you define a hierarchy based on parent and children. The has_child query allows you to query for the parent documents of which children match some queries.

Getting ready

You need a working ElasticSearch cluster and an index populated with the script chapter_05/populate_query.sh, available in the code bundle for this book.

How to do it...

In order to execute the has_child queries/filters, perform the following steps:

1. Search for the parents, test-type, for which the children, test-type2, have a term in the field value as value1. We can create this kind of query as follows:

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