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https://issues.apache.org/jira/browse/LUCENE-1470?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12651056#action_12651056
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Earwin Burrfoot commented on LUCENE-1470:
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bq. in base 2^15, you only have 4 precisions and some more bits
We have slightly different approaches. Yours is universal, and mine requires
hand-tuning. I have an abstract FastRangeFilter, which I extend, specifying
functions that lower precision before encoding, thus I have any required amount
of type/field-dependent precision levels. For further ease of use that one is
extended by FastDateRangeFilter, which accepts an array of date parts, like
{HOUR_OF_DAY, DAY_OF_MONTH}.
That allows me to exploit known statistical properties of my requests/data, for
example most date ranges are rolling day/week/month/3 months windows, or
salaries which tend to be attracted to certain values.
bq. Java sometimes has strange string comparisons, and I did not want to walk
into incompatiblities with String.compareTo()
Fact that java strings are UCS-16 (UTF-16 minus special non-16bit characters)
is written into java language specification, so you can trust
String.compareTo() - anything that blows up there, is not Java(tm). Problems
usually come from within libraries.
bq. I did not try to sort the results to my combined, prefixed field since long
time, and you are right, it is not possible, if all different precisions are in
the same field.
Actually, right now I'm -stealing- borrowing your idea of storing various
precisions in the same field. I have my own custom field cache, so broken sort
can be fixed easily. Having everything in the same field allows you to do
exactly one pass through TermEnum/TermDocs, and that is what I'm going to
exploit :)
> Add TrieRangeQuery to contrib
> -----------------------------
>
> Key: LUCENE-1470
> URL: https://issues.apache.org/jira/browse/LUCENE-1470
> Project: Lucene - Java
> Issue Type: New Feature
> Components: contrib/*
> Affects Versions: 2.4
> Reporter: Uwe Schindler
> Attachments: LUCENE-1470.patch
>
>
> According to the thread in java-dev
> (http://www.gossamer-threads.com/lists/lucene/java-dev/67807 and
> http://www.gossamer-threads.com/lists/lucene/java-dev/67839), I want to
> include my fast numerical range query implementation into lucene
> contrib-queries.
> I implemented (based on RangeFilter) another approach for faster
> RangeQueries, based on longs stored in index in a special format.
> The idea behind this is to store the longs in different precision in index
> and partition the query range in such a way, that the outer boundaries are
> search using terms from the highest precision, but the center of the search
> Range with lower precision. The implementation stores the longs in 8
> different precisions (using a class called TrieUtils). It also has support
> for Doubles, using the IEEE 754 floating-point "double format" bit layout
> with some bit mappings to make them binary sortable. The approach is used in
> rather big indexes, query times are even on low performance desktop
> computers <<100 ms (!) for very big ranges on indexes with 500000 docs.
> I called this RangeQuery variant and format "TrieRangeRange" query because
> the idea looks like the well-known Trie structures (but it is not identical
> to real tries, but algorithms are related to it).
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