Book Image

Elasticsearch 5.x Cookbook - Third Edition

By : Alberto Paro
Book Image

Elasticsearch 5.x Cookbook - Third Edition

By: Alberto Paro

Overview of this book

Elasticsearch is a Lucene-based distributed search server that allows users to index and search unstructured content with petabytes of data. This book is your one-stop guide to master the complete Elasticsearch ecosystem. We’ll guide you through comprehensive recipes on what’s new in Elasticsearch 5.x, showing you how to create complex queries and analytics, and perform index mapping, aggregation, and scripting. Further on, you will explore the modules of Cluster and Node monitoring and see ways to back up and restore a snapshot of an index. You will understand how to install Kibana to monitor a cluster and also to extend Kibana for plugins. Finally, you will also see how you can integrate your Java, Scala, Python, and Big Data applications such as Apache Spark and Pig with Elasticsearch, and add enhanced functionalities with custom plugins. By the end of this book, you will have an in-depth knowledge of the implementation of the Elasticsearch architecture and will be able to manage data efficiently and effectively with Elasticsearch.
Table of Contents (25 chapters)
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface

Introduction


In developing search solutions not only are results important, but they also help us to improve the quality and the search focus.

Elasticsearch provides a powerful tool to achieve these goals: the aggregations.

The main usage of aggregations is to provide additional data to the search results to improve their quality or to augment them with additional information.

For example, in a search for news articles, some facets that could be interesting to calculate, could be the authors who wrote the articles and the date histogram of the publishing date.

Thus aggregations are used not only to improve the results focus, but also to provide insight on stored data (analytics): this is the way that a lot of tools such as Kibana (https://www.elastic.co/products/kibana) are born.

Generally, the aggregations are displayed to the end user with graphs or a group of filtering options (for example, a list of categories for the search results).

Because the Elasticsearch aggregation framework provides...