In this chapter, we will focus on the basic concepts of Elasticsearch. We will start by explaining the building blocks and then discuss how to create, modify and query in Elasticsearch. Getting started with Elasticsearch is very easy; most operations come with default settings. The default settings can be overridden when you need more advanced features.
I first started using Elasticsearch in 2012 as a backend search engine to power our Analytics dashboards. It has been more than five years, and I never looked for any other technologies for our search needs. Elasticsearch is much more than just a search engine; it supports complex aggregations, geo filters, and the list goes on. Best of all, you can run all your queries at a speed you have never seen before. To understand how this magic happens, we will briefly discuss how Elasticsearch works internally and then discuss how to talk to Elasticsearch. Knowing how it works internally will help you understand its strengths and limitations. Elasticsearch, like any other open source technology, is very rapidly evolving, but the core fundamentals that power Elasticsearch don't change. By the end of this chapter, we will have covered the following:
- Basic concepts of Elasticsearch
- How to interact with Elasticsearch
- How to create, read, update, and delete
- How does search work
- Availability and horizontal scalability
- Failure handling
- Strengths and limitations
