Book Image

Apache Solr Enterprise Search Server - Third Edition

By : David Smiley, Eric Pugh, Kranti Parisa, Matt Mitchell
Book Image

Apache Solr Enterprise Search Server - Third Edition

By: David Smiley, Eric Pugh, Kranti Parisa, Matt Mitchell

Overview of this book

<p>Solr Apache is a widely popular open source enterprise search server that delivers powerful search and faceted navigation features—features that are elusive with databases. Solr supports complex search criteria, faceting, result highlighting, query-completion, query spell-checking, relevancy tuning, geospatial searches, and much more.</p> <p>This book is a comprehensive resource for just about everything Solr has to offer, and it will take you from first exposure to development and deployment in no time. Even if you wish to use Solr 5, you should find the information to be just as applicable due to Solr's high regard for backward compatibility. The book includes some useful information specific to Solr 5.</p>
Table of Contents (19 chapters)
Apache Solr Enterprise Search Server Third Edition
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Joining


In most real world applications, models share relationships of some kind, either directly through their attributes or through an association "table". Traditional database engines make use of foreign keys to describe relationships, and SQL joins are used to merge the record sets together.

Solr has limited support for joining via its join query parsers (join and block-join). These query parsers use the local-params syntax to describe relationships between documents—local-params was described earlier in this chapter.

Note

These parsers are not equal to SQL joins. The main difference between SQL and Solr in regard to joins is that the Solr joins do not merge related documents together in the search results. Solr joins are analogous to an SQL inner query in a WHERE clause.

The join query parser

The join query syntax takes two attributes, to and from, both of which accept field names as their values. The from field is used to link matching documents (those that matched the join query) to documents...