Oops, didn't notice that this was java-user. I had a Solr 'why write more code' reaction ?)
On Sat, Jul 31, 2010 at 1:56 PM, Uwe Schindler <u...@thetaphi.de> wrote: > We don't want to modify the ranking using functions, we want to switch some > queries to constant score mode. The QueryParser subclassing is just to make > it convenient. > > In general to strip off scores from queries, you use "new > ConstantScoreQuery(new QueryWrapperFilter(query))", this is used inside > Lucene, too (MultiTermQuery,...). The trick is to normalize the Scorer to > return a constant value (boost of CSQ). This can be done by first wrapping > the scorer of the original query in a filter and then add a scorer to the > filter again, that returns a constant. > > With function queries you can do something similar by returning a constant in > the CustomScoreProvider. The QWF/CSQ trick is more convenient and used quite > often inside Lucene, too. > > ----- > Uwe Schindler > H.-H.-Meier-Allee 63, D-28213 Bremen > http://www.thetaphi.de > eMail: u...@thetaphi.de > > >> -----Original Message----- >> From: Lance Norskog [mailto:goks...@gmail.com] >> Sent: Saturday, July 31, 2010 10:50 PM >> To: java-user@lucene.apache.org >> Subject: Re: Rank results only on some fields >> >> Can't this use case be done with a function query? >> >> On Sat, Jul 31, 2010 at 1:59 AM, Uwe Schindler <u...@thetaphi.de> wrote: >> > Here some example code, the method is getFieldQuery() (Lucene 2.9 or >> > 3.0 or following, don't use that approach before, because >> > QueryWrapperFilter is not effective before 2.9 for that): >> > >> > @Override >> > protected Query getFieldQuery(String field, String queryText) throws >> > ParseException { >> > Query q = super.getFieldQuery(field,queryText); >> > if (!"TITLE".equals(field)) >> > q = new ConstantScoreQuery(new QueryWrapperFilter(q)); >> > return q; >> > } >> > >> > I hope that explains itself. You may look at other Query type >> > factories in QP that produce scoring queries and wrap them similar. >> > But e.g. WildCard and RangeQueries are constant score. Phrases are also >> handled by this method. >> > Only the slop setting may not work correctly after this (look at the >> > instanceof checks in getFieldQuery(..., slop)). >> > >> > Uwe >> > >> > ----- >> > Uwe Schindler >> > H.-H.-Meier-Allee 63, D-28213 Bremen >> > http://www.thetaphi.de >> > eMail: u...@thetaphi.de >> > >> > >> >> -----Original Message----- >> >> From: Uwe Schindler [mailto:u...@thetaphi.de] >> >> Sent: Saturday, July 31, 2010 10:19 AM >> >> To: java-user@lucene.apache.org >> >> Subject: RE: Rank results only on some fields >> >> >> >> You can construct the query using a customized query parser that >> >> wraps all queries not with the suggested field name using a "new >> >> ConstantScoreQuery(new QueryWrapperFilter(originalCreatedQuery))". >> >> Override >> >> newFieldQuery() to do that and pass the super call to this ctor chain. >> >> >> >> Uwe >> >> >> >> ----- >> >> Uwe Schindler >> >> H.-H.-Meier-Allee 63, D-28213 Bremen >> >> http://www.thetaphi.de >> >> eMail: u...@thetaphi.de >> >> >> >> >> >> > -----Original Message----- >> >> > From: Philippe [mailto:mailer.tho...@gmail.com] >> >> > Sent: Saturday, July 31, 2010 10:04 AM >> >> > To: java-user@lucene.apache.org >> >> > Subject: Rank results only on some fields >> >> > >> >> > Hi, >> >> > >> >> > I want to rank my results only on parts of my query. E.g my query >> >> > is "TITLE:Lucene AND AUTHOR:Manning". After this query standard >> >> > lucene ranking for both fields take place. >> >> > >> >> > However, is it possible to query the index using the full query and >> >> > rank results only according to the "TITLE"-Field? >> >> > >> >> > Regards, >> >> > Philippe >> >> > >> >> > ------------------------------------------------------------------- >> >> > -- To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org >> >> > For additional commands, e-mail: java-user-h...@lucene.apache.org >> >> >> >> >> >> >> >> --------------------------------------------------------------------- >> >> To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org >> >> For additional commands, e-mail: java-user-h...@lucene.apache.org >> > >> > >> > >> > --------------------------------------------------------------------- >> > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org >> > For additional commands, e-mail: java-user-h...@lucene.apache.org >> > >> > >> >> >> >> -- >> Lance Norskog >> goks...@gmail.com >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org >> For additional commands, e-mail: java-user-h...@lucene.apache.org > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > For additional commands, e-mail: java-user-h...@lucene.apache.org > > -- Lance Norskog goks...@gmail.com --------------------------------------------------------------------- To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org For additional commands, e-mail: java-user-h...@lucene.apache.org
