Faceted Search - Enabling users to locate search items more efficiently and effectively

Faceted search is becoming a contemporary and de facto search methodology for content rich websites, in particular online stores and digital libraries. It is a resource discovery approach which has the propensity to enhance user experience.

There are a wide variety of tools that can be used to support faceted searching of catalogues and databases, including Blacklight, VuFind and Apache Solr (all of which can be found on our A-Z Glossary of FOSS for Libraries).

To investigate these issues, EIFL-FOSS organised two online sessions on Faceted Search Technologies as part of the EIFL-FOSS Themed Weeks Programme. The first session was a general introduction to faceted search and some of the key FOSS tools. The second session was a hands-on technical training session on Apache Solr, where delegates managed to successfully download, install and investigate the tool in real time.

The sessions were both presented by Boon Low, who has recently managed the JISC project 'Usability and Contemporary User Experience in Digital Libraries (UX2.0)', and developed digital library services for Enabling Grids for E-SciencE (EGEE) project. The services are based on custom-built web applications and engineered systems from off-the-shelf and open source systems including Apache Solr faceted/enterprise search infrastructure, Blacklight faceted search User Interface (Ruby on Rails), and Fedora Repository (Java).

View the news article about the general Faceted Search session (which includes links to the session recording and wiki)

View the news article about the hands-on training session on Apache Solr (which includes links to the session recording and wiki).

What is Faceted Search?

Faceted search (sometimes known as faceted browsing or faceted navigation), is a technique for accessing and exploring a collection of information (database, catalogue, repository).

It presents the user with a faceted (layered, categorised, grouped) classification, allowing them to explore by filtering available information.

A faceted search system allows each item in the catalogue/repository/database to be assigned multiple classifications, enabling the classifications to be ordered in multiple ways, rather than in a single, pre-determined, taxonomic order.

Facets can be derived manually from analysis of the item, or from pre-existing fields in the item's metadata such as author, descriptor, language, and format. The former enables facet to be derived and sourced via a range of user and content research methods. The latter permits existing items in a catalogue/repository/database to have this extra metadata extracted, mapped and presented as a navigation facet, without extra data input being needed.

What are the key benefits?

  • Enhanced feedback - users receive an overview of their search results broken down by category that they can then use for refining their search.
  • Informed choices - users know in advance how many items are available in each category, so they can search first in categories more likely to bring them a successful result. Categories with zero items in a given field are usually not shown, hence the user is very unlikely to encounter a 'no results' outcome.
  • Users can select their own searching path or hierarchy based on the information presented to them and can add or remove filters or facets at will.

What is Apache Solr?

  • Apache Solr is an open source faceted search platform developed by the Apache Lucene project. (The name is not indicative that it runs only on Apache servers - it operates on Windows, Mac OS, Linux etc). Solr is written in Java.

Case studies of Faceted Search tools in use