Book Image

Apache Solr Beginner's Guide

By : Alfredo Serafini
Book Image

Apache Solr Beginner's Guide

By: Alfredo Serafini

Overview of this book

<p>With over 40 billion web pages, the importance of optimizing a search engine's performance is essential.<br /><br />Solr is an open source enterprise search platform from the Apache Lucene project. Full-text search, faceted search, hit highlighting, dynamic clustering, database integration, and rich document handling are just some of its many features. Solr is highly scalable thanks to its distributed search and index replication.<br /><br />Solr is written in Java and runs as a standalone full-text search server within a servlet container such as Apache Tomcat or Jetty. Solr uses the Lucene Java search library at its core for full-text indexing and search, and has REST-like HTTP/XML and JSON APIs that make it usable with most popular programming languages. Solr's powerful external configuration allows it to be tailored to many types of application without Java coding, and it has a plugin architecture to support more advanced customization.<br /><br />With Apache Solr Beginner's Guide you will learn how to configure your own search engine experience. Using real data as an example, you will have the chance to start writing step-by-step, simple, real-world configurations and understand when and where to adopt this technology.<br /><br />Apache Solr Beginner's Guide will start by letting you explore a simple search over real data. You will then go through a step-by-step description that gives you the chance to explore several practical features. At the end of the book you will see how Solr is used in different real-world contexts.<br /><br />Using data from public domains like DBpedia, you will define several different configurations, exploring some of the most interesting Solr features, such as faceted search and navigation, auto-suggestion, and rich document indexing. You will see how to configure different analysers for handling different data types, without programming.<br /><br />You will learn the basics of Solr, focusing on real-world examples and practical configurations.</p>
Table of Contents (19 chapters)
Apache Solr Beginner's Guide
Credits
About the Author
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface
Index

Introducing group and field collapsing


Once you have played with some examples, at some point, you will probably be curious about the possibility to view results, grouped by a certain field value, in a similar way to what is possible with SQL.

From Solr's point of view, this functionality is intended to be used in two scenarios:

  • Field collapsing: It is used when we want to collapse a group of results into a certain amount of entries, aggregating them by a common field value. This is a typical case for search engines or internal engines on large datasets, and it is generally useful to provide only the top results for some value choices to give an idea on what the users should expect with some link to the complete series of results. This is somewhat similar (from a different point of view) to what we have done with the wordclouds prototype; so, this approach will be useful when you have lots of shared values, and it's not complex to use some HTML or JavaScript to produce the query for the complete...