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https://issues.apache.org/jira/browse/LUCENE-5879?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14371671#comment-14371671
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Robert Muir commented on LUCENE-5879:
-------------------------------------
{quote}
I.e., with the patch as it is now, PFs like SimpleText will use a
PrefixTermsEnum for PrefixQuery, but if I fix PrefixQuery to subclass
AutomatonQuery (and remove AUTOMATON_TYPE.PREFIX) then SimpleText
would use AutomatonTermsEnum (on a prefix automaton) which I think
will be somewhat less efficient? Maybe it's not so bad in practice? ATE
would realize it's in a "linear" part of the automaton...
{quote}
We cannot continue writing code in this way.
Please let intersect take care of how to intersect and get this shit out of the
Query. The default Terms.intersect() method can specialize the PREFIX case with
a PrefixTermsEnum if it is faster.
> 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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