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Simon Willnauer updated LUCENE-2878: ------------------------------------ Attachment: LUCENE-2878.patch Attaching my current state - still rough & work in progress though.... In this patch I added a PositionsIntervalIterator returned from Scorer#positions() and implemented some usecases like filtering Near / Within (unordered) with Term & BooleanScorer2. BooleanScorer2 if in conjunction mode now has a PositionIntervalIter implementation that returns the minimal interval of its unordered query terms and can easily be filtered within a range of pos (range, first) or within a relative positions (near) simply by wrapping it in PositionFilterQuery. An example for this is in TestBooleanQuery. The PosIntervalIterator decouples positional operation nicely from Scoring / matching so a Boolean AND query gets the normal query score but can be restricted further based on positions. Even adding positional scoring can simple be plugged on top of it. Further, with a specialized Collector implementation - positions could be fetched only if the score is within the top N to prevent positions matching for all documents. One big problem is BooleanScorer which does the bucket based scoring - I will ignore that one for now. I need to run some benchmarks to see if that does any good though but haven't had time to do so. If somebody has time and take a look at this patch - feedback would be very much appreciated. > Allow Scorer to expose positions and payloads aka. nuke spans > -------------------------------------------------------------- > > Key: LUCENE-2878 > URL: https://issues.apache.org/jira/browse/LUCENE-2878 > Project: Lucene - Java > Issue Type: Improvement > Components: Search > Affects Versions: Bulk Postings branch > Reporter: Simon Willnauer > Assignee: Simon Willnauer > Attachments: LUCENE-2878.patch, LUCENE-2878.patch, LUCENE-2878.patch > > > Currently we have two somewhat separate types of queries, the one which can > make use of positions (mainly spans) and payloads (spans). Yet Span*Query > doesn't really do scoring comparable to what other queries do and at the end > of the day they are duplicating lot of code all over lucene. Span*Queries are > also limited to other Span*Query instances such that you can not use a > TermQuery or a BooleanQuery with SpanNear or anthing like that. > Beside of the Span*Query limitation other queries lacking a quiet interesting > feature since they can not score based on term proximity since scores doesn't > expose any positional information. All those problems bugged me for a while > now so I stared working on that using the bulkpostings API. I would have done > that first cut on trunk but TermScorer is working on BlockReader that do not > expose positions while the one in this branch does. I started adding a new > Positions class which users can pull from a scorer, to prevent unnecessary > positions enums I added ScorerContext#needsPositions and eventually > Scorere#needsPayloads to create the corresponding enum on demand. Yet, > currently only TermQuery / TermScorer implements this API and other simply > return null instead. > To show that the API really works and our BulkPostings work fine too with > positions I cut over TermSpanQuery to use a TermScorer under the hood and > nuked TermSpans entirely. A nice sideeffect of this was that the Position > BulkReading implementation got some exercise which now :) work all with > positions while Payloads for bulkreading are kind of experimental in the > patch and those only work with Standard codec. > So all spans now work on top of TermScorer ( I truly hate spans since today ) > including the ones that need Payloads (StandardCodec ONLY)!! I didn't bother > to implement the other codecs yet since I want to get feedback on the API and > on this first cut before I go one with it. I will upload the corresponding > patch in a minute. > I also had to cut over SpanQuery.getSpans(IR) to > SpanQuery.getSpans(AtomicReaderContext) which I should probably do on trunk > first but after that pain today I need a break first :). > The patch passes all core tests > (org.apache.lucene.search.highlight.HighlighterTest still fails but I didn't > look into the MemoryIndex BulkPostings API yet) -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online. --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org