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https://issues.apache.org/jira/browse/LUCENE-1252?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14176689#comment-14176689
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Michael McCandless commented on LUCENE-1252:
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+1 to this plan.
Except if possible, I think "high cost filters" really should be first class in
Lucene? I think the "two-phase execution" is in fact the same problem?
I.e., a PhraseQuery should just rewrite itself into a conjunction of two
clauses: the "pure conjunction" of the terms, which is fast to execute, AND'd
with a high-cost filter (that loads positions and checks that the terms are
actually a phrase). If BQ knew how to juggle such costly clauses then this
issue (AND'ing a PhraseQuery with other simple clauses) and other example like
geo filtering (which could rewrite into a cheap bbox AND'd w/ slow true
distance check) should work well.
But if somehow making high cost filters first class is too much, then I agree:
let's punt, here. It just seems to me that it's the same issue as two-phase
execution...
> Avoid using positions when not all required terms are present
> -------------------------------------------------------------
>
> Key: LUCENE-1252
> URL: https://issues.apache.org/jira/browse/LUCENE-1252
> Project: Lucene - Core
> Issue Type: Wish
> Components: core/search
> Reporter: Paul Elschot
> Priority: Minor
> Labels: gsoc2014
>
> In the Scorers of queries with (lots of) Phrases and/or (nested) Spans,
> currently next() and skipTo() will use position information even when other
> parts of the query cannot match because some required terms are not present.
> This could be avoided by adding some methods to Scorer that relax the
> postcondition of next() and skipTo() to something like "all required terms
> are present, but no position info was checked yet", and implementing these
> methods for Scorers that do conjunctions: BooleanScorer, PhraseScorer, and
> SpanScorer/NearSpans.
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