My guess is that it's an advantage of doing the sort in-memory and reusing caches. Hard to tell without the snippet of code that you're actually using.
Dawid On Fri, Jun 24, 2011 at 8:04 AM, Denis Bazhenov <dot...@gmail.com> wrote: > Yes, sorry. I should explain it. > > What we are using is sorting by field value. We have around 1M documents > which we are searching and returns them to the user in reverse order by > creation date. Creation date is indexed in separated field in lucene of > course. > > On Jun 24, 2011, at 4:52 PM, Dawid Weiss wrote: > >> Can you describe the kind of sorting you're doing? Maybe the data is >> already sorted (and in RAM) and you're only getting it out? >> >> Dawid >> >> On Fri, Jun 24, 2011 at 3:32 AM, Denis Bazhenov <dot...@gmail.com> wrote: >>> Well, maybe it's a bit controversial question, but anyway... >>> >>> Lucene is a great toolkit for search applications. And it's so fast in most >>> of cases. I think I am understand why it's faster than relational databases >>> for information retrieval. For example, Lucene use very efficient index >>> than allows to retrieve posting list in constant time and do intersect >>> between them. >>> >>> But there is one aspect which I couldn't understand for a long time now. In >>> our test cases Lucene perform sorting blazingly fast. This one is freaking >>> me out. I have no explanation why Lucene should do sorting faster than >>> relational database. Let me put it another way -- I have no explanation why >>> SQL databases should not do it as fast as Lucene. >>> >>> Is there any explanation for that? >>> --- >>> Denis Bazhenov <dot...@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 >> > > --- > Denis Bazhenov <dot...@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
