lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Yonik Seeley" <yo...@apache.org>
Subject Re: Re[2]: ParallelMultiSearcher
Date Thu, 21 Sep 2006 16:20:39 GMT
On 9/21/06, Yura Smolsky <info@altervisionmedia.com> wrote:

> ok. I have big issue when I try to search ParallelMultiSearcher for
> PrefixQuery. This query is being rewritten to BooleanQuery during
> search. This causes Similarity to calculate docFreq for each Term in the
> BooleanQuery. So if we have a lot of results for some PrefixQuery then
> we have a lot of calls to docFreq method of Searchable object passed
> to ParallelMultiSearcher.

IDF often does not make sense for auto-expanding queries (range, prefix, etc).
If you don't need the idf factor that makes rarer terms count more,
then use a PrefixFilter wrapped in a ConstantScoreQuery.

http://lucene.apache.org/java/docs/api/org/apache/lucene/search/ConstantScoreQuery.html
http://incubator.apache.org/solr/docs/api/org/apache/solr/search/PrefixFilter.html

-Yonik
http://incubator.apache.org/solr Solr, the open-source Lucene search server

---------------------------------------------------------------------
To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
For additional commands, e-mail: java-user-help@lucene.apache.org


Mime
View raw message