DBSight is a powerful tool for web developers to create scalable database full-text search in Lucene.
You can create a full-text database search service, return results as HTML/XML/JSON. It uses the Lucene directly in java, but can be easily used with Ruby, PHP, or any existing database web applications.
You can easily index, re-index, incremental-index. It's also highly scalable and easily customizable.
The best thing is, it's free and super easy. You can create a production-level search in 3 minutes.
Usually, in order to tune database SQL query performance, you need adjust the database index. Similarly, you usually want to add/change your full-text search. By making database full-text search super easy to create or change, you can quickly get a full-text search just for your own needs.
1.4.1 is a major upgrade full of more useful features:
Upgrade to jdk 1.5
Added multiple keywords, support displaying tag cloud in search results
Much faster bulk deleting old documents (thanks for bastien's suggestion)
Added jruby support for indexing
Faster copying on linux environment
Faster merging indexes
Memory-efficiently find out deleted documents
Fix query parser: analyzer was applied twice
Fix index file uploading error from windows to linux systems