Book Image

Mastering Elasticsearch 5.x - Third Edition

By : Bharvi Dixit
Book Image

Mastering Elasticsearch 5.x - Third Edition

By: Bharvi Dixit

Overview of this book

Elasticsearch is a modern, fast, distributed, scalable, fault tolerant, and open source search and analytics engine. Elasticsearch leverages the capabilities of Apache Lucene, and provides a new level of control over how you can index and search even huge sets of data. This book will give you a brief recap of the basics and also introduce you to the new features of Elasticsearch 5. We will guide you through the intermediate and advanced functionalities of Elasticsearch, such as querying, indexing, searching, and modifying data. We’ll also explore advanced concepts, including aggregation, index control, sharding, replication, and clustering. We’ll show you the modules of monitoring and administration available in Elasticsearch, and will also cover backup and recovery. You will get an understanding of how you can scale your Elasticsearch cluster to contextualize it and improve its performance. We’ll also show you how you can create your own analysis plugin in Elasticsearch. By the end of the book, you will have all the knowledge necessary to master Elasticsearch and put it to efficient use.
Table of Contents (20 chapters)
Mastering Elasticsearch 5.x - Third Edition
About the Author
About the Reviewer
Customer Feedback


In this chapter, we explained scoring and its new default similarity ranking algorithm, BM25, along with explaining the difference between BM25 and TF-IDF, the previous ranking algorithm used in Apache Lucene. In addition to that, we discussed precision and recall, the fundamentals of search relevancy.

After that, we discussed Elasticsearch Query DSL in detail and covered the important queries with their use cases. We also saw the new bool query syntax and how one can use filters within the query context of the bool query. The chapter also covered a detailed discussion about using query rewrites and using search templates along with the Mustache template engine.

In the next chapter, you will learn about query rescoring and how search works in multimatch scenarios, such as cross-field matching and phrase matching. We will also cover various ways to use scripting in Elasticsearch.