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https://issues.apache.org/jira/browse/LUCENE-5879?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14367397#comment-14367397
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Robert Muir commented on LUCENE-5879:
-------------------------------------
{quote}
The added auto-prefix terms are not seen by normal postings APIs, they
do not affect index stats, etc. They only kick in, as an
implementation detail, when you call Terms.intersect(Automaton). The
returned TermsEnum.term() can return an auto-prefix term, but
LUCENE-5938 improves this since we now use
MultiTermQueryConstantScoreWrapper by default.
{quote}
I can't parse this. if you use a scoring rewrite, it still "works" right? Its
just that the generated termqueries will contain pseudo-terms, but their
statistics etc are all correct?
> Add auto-prefix terms to block tree terms dict
> ----------------------------------------------
>
> Key: LUCENE-5879
> URL: https://issues.apache.org/jira/browse/LUCENE-5879
> Project: Lucene - Core
> Issue Type: New Feature
> Components: core/codecs
> Reporter: Michael McCandless
> Assignee: Michael McCandless
> Fix For: 5.0, Trunk
>
> Attachments: LUCENE-5879.patch, LUCENE-5879.patch, LUCENE-5879.patch,
> LUCENE-5879.patch, LUCENE-5879.patch, LUCENE-5879.patch, LUCENE-5879.patch,
> LUCENE-5879.patch, LUCENE-5879.patch, LUCENE-5879.patch, LUCENE-5879.patch
>
>
> This cool idea to generalize numeric/trie fields came from Adrien:
> Today, when we index a numeric field (LongField, etc.) we pre-compute
> (via NumericTokenStream) outside of indexer/codec which prefix terms
> should be indexed.
> But this can be inefficient: you set a static precisionStep, and
> always add those prefix terms regardless of how the terms in the field
> are actually distributed. Yet typically in real world applications
> the terms have a non-random distribution.
> So, it should be better if instead the terms dict decides where it
> makes sense to insert prefix terms, based on how dense the terms are
> in each region of term space.
> This way we can speed up query time for both term (e.g. infix
> suggester) and numeric ranges, and it should let us use less index
> space and get faster range queries.
>
> This would also mean that min/maxTerm for a numeric field would now be
> correct, vs today where the externally computed prefix terms are
> placed after the full precision terms, causing hairy code like
> NumericUtils.getMaxInt/Long. So optos like LUCENE-5860 become
> feasible.
> The terms dict can also do tricks not possible if you must live on top
> of its APIs, e.g. to handle the adversary/over-constrained case when a
> given prefix has too many terms following it but finer prefixes
> have too few (what block tree calls "floor term blocks").
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