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 the spellcheck component


When we refer to the spellchecker, we think about a component that is able to recognize small typos and errors over a term inserted by a casual user. In short, the component works by applying some distance between the terms in search and the terms indexed. When the distance will give results lesser than a certain value, a suggestion will be returned. Nothing is conceptually complicated then, and the component works generally almost well out of the box. Still it's important to do some fine tuning in order to have it work as expected; we always have to remember that if we use only the terms in our index, our precision can degrade very fast due to the domain-specific nature of our application, and to the quantity of the terms we have indexed.

Spellchecking can be seen somehow similar to obtaining suggestions for similar topics. This is one of the most commonly used ways to implement with Solr a functionality similar to the well-know ''did you mean'' by Google...