Lucene vs Sphinx
From WikiVS, the open comparison website
Lucene and Sphinx are open-source search engines. Sphinx is a stand-alone project and Lucene is maintained by Apache.
[edit] Features
Lucene supports live updates to the index whereas Sphinx requires you to reindex the whole index whenever there's an update.
Sphinx supports direct imports from MySQL or PostgreSQL for faster indexing speeds.
[edit] Performance
Lucene and Sphinx are both very scalable. Lucene backs the search features of Wikipedia and Digg.
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