Chapter 6: Relationships and Geo Queries
In this chapter, we will explore special queries that can be used to search for relationships between Elasticsearch and geolocation documents.
When we have a parent-child relationship (based on a join field mapping), we can use special queries to query for a similar relationship. Elasticsearch doesn't provide a SQL join, but it lets you search child/parent-related documents; it makes it possible to retrieve child documents via parent selection or by matching parent documents and filtering them by their children. Elasticsearch is very powerful tool and can help resolve many common data relationship issues. It is also used to easily solve issues in traditional relational databases. These features, in my experience, aren't popular among new Elasticsearch users but are valuable if you manage intelligence data sources.
In this chapter, we will also look at how to query nested objects using...
