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Shai Erera commented on LUCENE-5460: ------------------------------------ There is a TODO in FilteredQuery.RandomAccessFilterStrategy.useRandomAccess() to use filter.cost() instead of the heuristic to return true if the first filtered doc is < 100. Do you mean that? RandomAccess is the default FilterStrategy, but the app can pass LEAP_FROG_FILTER_FIRST_STRATEGY to FilteredQuery. > Allow driving a query by sparse filters > --------------------------------------- > > Key: LUCENE-5460 > URL: https://issues.apache.org/jira/browse/LUCENE-5460 > Project: Lucene - Core > Issue Type: Improvement > Components: core/search > Reporter: Shai Erera > > Today if a filter is very sparse we execute the query in sort of a leap-frog > manner between the query and filter. If the query is very expensive to > compute, and/or matching few docs only too, calling scorer.advance(doc) just > to discover the doc it landed on isn't accepted by the filter, is a waste of > time. Since Filter is always the "final ruler", I wonder if we had something > like {{boolean DISI.advanceExact(doc)}} we could use it instead, in some > cases. > There are many combinations in which I think we'd want to use/not-use this > API, and they depend on: Filter's complexity, Filter.cost(), Scorer.cost(), > query complexity (span-near, many clauses) etc. > I open an issue so we can discuss. DISI.advanceExact(doc) is just a > preliminary proposal, to get an API we could experiment with. The default > implementation should be fairly easy and straightforward, and we could > override where we can offer a more optimized imp. -- This message was sent by Atlassian JIRA (v6.1.5#6160) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org