Sphinx is a full-text search engine, distributed under GPL version 2. a standalone search engine, meant to provide fast, size-efficient and relevant fulltext search functions to other applications. Sphinx was specially designed to integrate well with SQL databases and scripting languages. Currently built-in data source drivers support fetching data either via direct connection to MySQL, PostgreSQL, or from a pipe in a custom XML format.
What is great with Sphinx that it came with a pure-PHP searchd client API, this will make its integration with PHP application much more easier. In addition to many features that make Sphinx a very interesting alternative to an open source SQL full-text search engine.


Key features Sphinx :

  • high indexing speed (upto 10 MB/sec on modern CPUs)
  • high search speed (avg query is under 0.1 sec on 2-4 GB text collections)
  • high scalability (upto 100 GB of text, upto 100 M documents on a single CPU)
  • supports distributed searching (since v.0.9.6)
  • supports MySQL natively (MyISAM and InnoDB tables are both supported)
  • supports phrase searching
  • supports phrase proximity ranking, providing good relevance
  • supports English and Russian stemming
  • supports any number of document fields (weights can be changed on the fly)
  • supports document groups
  • supports stopwords
  • supports different search modes (“match all”, “match phrase” and “match any” as of v.0.9.5)
  • generic XML interface which grealy simplifies custom integration
  • pure-PHP (ie. NO module compiling etc) searchd client API


Current Sphinx distribution includes the following software:

  • indexer: an utility to create fulltext indices;
  • search: a simple (test) utility to query fulltext indices from command line;
  • searchd: a daemon to search through fulltext indices from external software (such as Web scripts);
  • sphinxapi: a set of API libraries for popular Web scripting languages (currently, PHP);

Download
You can download Sphinx from http://www.sphinxsearch.com/downloads.html
Documentation available on http://www.sphinxsearch.com/doc.html#installation
Sphinx is Open Source under GPL license but Commercial license is also available for embedded use.