A 100% accurate count of distinct values (count distinct) is not generally possible without actually observing all of the values together. However there are a number of ways to estimate the count. “unique” Facet Function The unique facet function is Solr’s fastest implementation to calculate the number of distinct values. […]

Count Distinct in Solr


Related Pages Facet Functions Sub-Facets Multi-Select Faceting Nested Documents / Block Join Faceting Facet Performance Benchmarks Introduction Solr 5 has a completely re-written faceted search and analytics module with a structured JSON API to control the faceting and analytics commands. NOTE: Some examples use syntax only supported in later Solr […]

JSON Facet API


Subfacets (also called Nested Facets) is a more generalized form of Solr’s current pivot faceting that allows adding additional facets for every bucket produced by a parent facet. Subfacet advantages over pivot faceting: Subfacets work with facet functions (statistics), enabling powerful real-time analytics Can add a subfacet to any facet […]

Solr Subfacets



Traditional faceted search (also called guided navigation) involves counting search results that belong to categories (also called facet constraints). The new facet functions in Solr extends normal faceting by allowing additional aggregations on document fields themselves. Combined with the new Sub-facet feature, this provides powerful new realtime analytics capabilities. Also […]

Solr Facet Functions and Analytics


Solr 5.1 has been released! Here’s an overview of how to use some of the new features. Also see Solr download links and upcoming features of the next Solr release. New Facet Module The new facet module has a native JSON Facet API, first-class support for statistics and analytics via […]

Solr 5.1 Features


Here’s an overview of some of the new features in Solr 5.2 Also see Solr download links and upcoming features of the next Solr release. Solr caches can be limited by memory use Caches using the LRUCache implementation can specify a new parameter maxRamMB that will evict based on RAM […]

Solr 5.2 Features



The percentile aggregation function was just added to the new Solr Facet Module. This allows one to calculate one or more percentiles for each facet bucket (i.e. each group of documents produced by faceting), and even sort facet buckets by any given percentile. The percentile aggregation even works with distributed […]

Percentiles for Solr Faceting


The Solr 5 Tutorial is Here Getting Started with Solr: a Simple Solr Tutorial Note: this tutorial is for Solr 4 1. Download Solr Download Apache Solr 4. You only need to download the single .ZIP or .TGZ file and extract it anywhere you like – no installation is required!! […]

Getting Started with Solr


Noggit is the world’s fastest streaming JSON parser for Java. Noggit is the streaming JSON parser used in Solr. It lives here on github. JSON features and extensions Noggit supports a number of extensions to the JSON grammar. All of these extensions are optional and may be disabled. Comments Unquoted […]

Noggit, the JSON Streaming Parser



Lucene/Solr trunk (the future 6.0 release) is now on Java8, while version 5.x is still on Java7. Linux and Windows allows one to install a JDK any place in the filesystem, and I use the convention of installing in /opt/jdk7 and /opt/jdk8. Things are a little more difficult on Mac […]

Switching between Java7 and Java8 in Lucene/Solr