Book Image

Mastering Elasticsearch 5.x - Third Edition

Book Image

Mastering Elasticsearch 5.x - Third Edition

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
Credits
About the Author
Acknowledgements
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Data analytics using aggregations


Elasticsearch is a search engine at its core but what makes it more usable is its ability to perform complex data analytics in an easy and simple way. The volume of data is growing rapidly and companies want to perform analysis on data in real-time. Whether it is log, real-time streaming of data, or static data, Elasticsearch works wonderfully in creating a summarization of data through its aggregation capabilities.

In the previous editions of Mastering Elasticsearch we have covered a lot of ground on aggregations but we will revisit the important aggregations in this chapter again, and then cover the new aggregation type which is introduced in Elasticsearch version 5.x.

Instant aggregations in Elasticsearch 5.0

Aggregations were too costly at the beginning of Elasticsearch and used to be the biggest consumer of memory. In Elasticsearch 1.4, there was a new feature which was known as shard query cache, which was further renamed shard request cache. The benefit...