BTW eks, you asked about reusing TSDC. PQ has a clear() method, so it can be reused. Only currently it's final and nullifies the array. We'll need to un-final it, and then override in HitQueue to just reset the ScoreDoc instances to be sentinels again. And of course add a reset() method to TSDC.
On Wed, Sep 30, 2009 at 5:26 PM, eks dev <eks...@yahoo.co.uk> wrote: > Thanks Mark, Shai, > I was getting confused by so many possibilities to do the "almost the same > thing" ;) > > But have figured it out by peeking into BoolenQuery code that decides if > "out of order" should be used..., BQ will pick the right TSDC ... I like it, > option 1 it is minimum user code. > > Cheers, eks > > > > ----- Original Message ---- > > From: Shai Erera <ser...@gmail.com> > > To: java-user@lucene.apache.org > > Sent: Wednesday, 30 September, 2009 17:12:38 > > Subject: Re: TSDC, TopFieldCollector & co > > > > I agree. If you need sort-by-score, it's better to use the "fast" search > > methods. IndexSearcher will create the appropriate TSDC instance for you, > > based on the Query that was passed. > > > > If you need to create multiple Collectors and pass a kind of > Multi-Collector > > to IndexSearcher, then you should create TSDC according to Mark's example > > above. > > > > Shai > > > > On Wed, Sep 30, 2009 at 4:57 PM, Mark Miller wrote: > > > > > If you want relevance sorting (Sort.Score not Sort.Relevance right?), > > > I'd think you want to use TopScoreDocCollector, not TopFieldCollector. > > > The only reason to use relevance with TopFieldCollector is if you you > > > are doing a nth sort with a field sort as well. > > > > > > You don't really need to worry about things like turning off the max > > > score tracking here - its just going to be the first doc on the queue. > > > > > > You also do want to specify whether or not to collect docs in order if > > > you care about performance: > > > > > > public static TopScoreDocCollector create(int numHits, boolean > > > docsScoredInOrder) > > > > > > ie: > > > > > > TopScoreDocCollector.create(nDocs, !weight.scoresDocsOutOfOrder()); > > > > > > Which means you just want option 1. > > > > > > -- > > > - Mark > > > > > > http://www.lucidimagination.com > > > > > > > > > > > > eks dev wrote: > > > > Hi All, > > > > > > > > What is the best way to achieve the following and what are the > > > differences, if I say "I do not normalize scores, so I do not need max > score > > > tracking, I do not care if hits are returned in doc id order, or any > other > > > order. I need only to get maxDocs *best scoring* documents": > > > > > > > > OPTION 1: > > > > TopDocs top = ixSearcher.search(q, filter, maxDocs); > > > > > > > > OPTION 2: > > > > final TopScoreDocCollector tfc = > TopScoreDocCollector.create(maxDocs, > > > false); > > > > ixSearcher.search(q, filter, tfc); > > > > TopDocs top = tfc.topDocs(); > > > > > > > > > > > > OPTION 3: > > > > final TopFieldCollector tfc = > > > TopFieldCollector.create(Sort.RELEVANCE, maxDocs, > > > > false /* fillFields */, > > > > true /* trackDocScores */, > > > > false /* trackMaxScore */, > > > > false /* docsInOrder */); > > > > > > > > ixSearcher.search(q.weight(ixSearcher),filter, tfc); > > > > TopDocs top = tfc.topDocs(); > > > > > > > > > > > > what are the pros and cons? > > > > If I read javadoc correctly, > > > > - OPTION 1 tracks max score and delivers doc Ids in order (suboptimal > > > performance for my case) > > > > - OPTION 2 I do not know abut max score tracking, but doc Ids are not > > > required to be in order > > > > - OPTION 3 looks like exactly what I want, but one performance > comment in > > > javadoc about Sort.RELEVANCE made me think if that is the fastest way? > > > > > > > > What would be recommended here, any other options to achieve the > fastest > > > search with above defined conditions (no max score tracking and doc id > order > > > irrelevant)? OPTIN2 looks nice, but as said, I am not sure about max > score > > > tracking? > > > > > > > > Thanks, > > > > eks > > > > > > > > > > > > > > > > > > > > --------------------------------------------------------------------- > > > > 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 > >
