Book Image

Apache Solr for Indexing Data

Book Image

Apache Solr for Indexing Data

Overview of this book

Apache Solr is a widely used, open source enterprise search server that delivers powerful indexing and searching features. These features help fetch relevant information from various sources and documentation. Solr also combines with other open source tools such as Apache Tika and Apache Nutch to provide more powerful features. This fast-paced guide starts by helping you set up Solr and get acquainted with its basic building blocks, to give you a better understanding of Solr indexing. You’ll quickly move on to indexing text and boosting the indexing time. Next, you’ll focus on basic indexing techniques, various index handlers designed to modify documents, and indexing a structured data source through Data Import Handler. Moving on, you will learn techniques to perform real-time indexing and atomic updates, as well as more advanced indexing techniques such as de-duplication. Later on, we’ll help you set up a cluster of Solr servers that combine fault tolerance and high availability. You will also gain insights into working scenarios of different aspects of Solr and how to use Solr with e-commerce data. By the end of the book, you will be competent and confident working with indexing and will have a good knowledge base to efficiently program elements.
Table of Contents (18 chapters)
Apache Solr for Indexing Data
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Using RealTime Get


Solr also provides us with a way to see documents that are sent to it for indexing but are not indexed or have a commit/soft commit time in the future. This feature also makes Solr behave like a NoSQL data store, wherein we can fetch a document by unique key.

Let's see how we can use this feature in Solr by performing the following steps:

  1. Let's add the RealTime Get (/get) request handler to solr-config.xml, as follows:

      <requestHandler name="/get" class="solr.RealTimeGetHandler">
        <lst name="defaults">
          <str name="omitHeader">true</str>
          <str name="wt">json</str>
          <str name="indent">true</str>
        </lst>
      </requestHandler>
  2. After adding requestHandler, we'll need to change updateLog in updateHandler. This is because RealTime Get uses the updateLog feature to work. The updateLog element or transaction log is a feature in Solr wherein data is written to a transaction log file before indexing. During...