Solr features caching, replication support for load balancing, faceting, highlighting, more-like-this, simple HTTP protocol supporting XML, JSON, and other formats. Lucene powers Solr’s RESTful web services.
Solr is an enterprise-ready, Lucene-based search server that supports faceted searching, hit highlighting, and multiple output formats.
Solr Uses the Lucene Search Library and Extends it!
* A Real Data Schema, with Numeric Types, Dynamic Fields, Unique Keys
* Powerful Extensions to the Lucene Query Language
* Support for Dynamic Faceted Browsing and Filtering
* Advanced, Configurable Text Analysis
* Highly Configurable and User Extensible Caching
* Performance Optimizations
* External Configuration via XML
* An Administration Interface
* Monitorable Logging
* Fast Incremental Updates and Snapshot Distribution
* XML and CSV/delimited-text update formats
An example of a Solr admin screen: