Thanks for the explanation Mike. It looks like I have no choice but to move any queries which throw TooManyClauses to be Filters. Sadly, this means a max query time of 6s under load unless I can find a way to rewrite the query to span a Query and a Filter.
Thanks again On Thu, Oct 15, 2009 at 6:52 PM, Michael McCandless < luc...@mikemccandless.com> wrote: > On Thu, Oct 15, 2009 at 4:57 AM, Shaun Senecal <ssenecal.w...@gmail.com> > wrote: > > > Up to Lucene 2.4, this has been working out for us. However, in > > Lucene 2.9 this breaks since rewrite() now returns a > > ConstantScoreQuery. > > You can get back to the 2.4 behavior by calling > prefixQuery.setRewriteMethod(prefixQuery.SCORING_BOOLEAN_QUERY_REWRITE) > before calling rewrite(). > > > Is there a way I can know that a ConstantScoreQuery will match at > > least 1 term (if not, I dont want to add it to the BooleanQuery)? > > There is a new method in 2.9: MultiTermQuery.getTotalNumberOfTerms(), > which returns how many terms were visited during rewrite. Would that > work? > > > My understanding is that Lucene will apply the Filter (C | D) first, > > limiting the result set, then apply the Query (A | B). Is this > > correct? > > Actually the filter & query clauses are AND'd in a sort of leapfrog > fashion, taking turns skipping up to the other's doc ID and only > accepting a doc ID when they both skip to the same point. But this > (the mechanics of how Lucene takes a filter into account) is an > implementation detail and is likely to change. > > > If so, the end result is essentially the query: (A | B) & (C | D) > > Except that C, D contribute no scoring information, if scoring > matters. If scoring doesn't matter, entirely (even for A, B), you > should use a collector that does not call score() at all to save CPU. > > Mike > > --------------------------------------------------------------------- > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > For additional commands, e-mail: java-user-h...@lucene.apache.org > >
