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https://issues.apache.org/jira/browse/LUCENE-5205?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13923915#comment-13923915
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Tim Allison commented on LUCENE-5205:
-------------------------------------
The root of this problem is that SpanNearIQuery has no good way to handle
stopwords in a way analagous to PhraseQuery.
In SpanQueryParser, this limitation should be well described in the javadocs to
SpanQueryParser and in the test cases. Let me know if it isn't. You have the
option of throwing an exception when a stopword is found to notify the user
about stopwords, but that's exceedingly unsatisfactory.
Without digging into the internals of SpanNearQuery, we can still do better on
this. One proposal is to do what the basic highlighter does and risk false
positives...behind the scenes modify "calculator for evaluating" to "calculator
evaluating"~>1. This would then falsely match "calculator zebra evaluating."
PhraseQuery can have false positives, too, but it guarantees that the false hit
has to be a stop word. This solution would not do that. So, is this better
than no matches at all?
> [PATCH] SpanQueryParser with recursion, analysis and syntax very similar to
> classic QueryParser
> -----------------------------------------------------------------------------------------------
>
> Key: LUCENE-5205
> URL: https://issues.apache.org/jira/browse/LUCENE-5205
> Project: Lucene - Core
> Issue Type: Improvement
> Components: core/queryparser
> Reporter: Tim Allison
> Labels: patch
> Fix For: 4.7
>
> Attachments: LUCENE-5205-cleanup-tests.patch,
> LUCENE-5205-date-pkg-prvt.patch, LUCENE-5205.patch.gz, LUCENE-5205.patch.gz,
> LUCENE-5205_dateTestReInitPkgPrvt.patch, LUCENE-5205_smallTestMods.patch,
> LUCENE_5205.patch, SpanQueryParser_v1.patch.gz, patch.txt
>
>
> This parser extends QueryParserBase and includes functionality from:
> * Classic QueryParser: most of its syntax
> * SurroundQueryParser: recursive parsing for "near" and "not" clauses.
> * ComplexPhraseQueryParser: can handle "near" queries that include multiterms
> (wildcard, fuzzy, regex, prefix),
> * AnalyzingQueryParser: has an option to analyze multiterms.
> At a high level, there's a first pass BooleanQuery/field parser and then a
> span query parser handles all terminal nodes and phrases.
> Same as classic syntax:
> * term: test
> * fuzzy: roam~0.8, roam~2
> * wildcard: te?t, test*, t*st
> * regex: /\[mb\]oat/
> * phrase: "jakarta apache"
> * phrase with slop: "jakarta apache"~3
> * default "or" clause: jakarta apache
> * grouping "or" clause: (jakarta apache)
> * boolean and +/-: (lucene OR apache) NOT jakarta; +lucene +apache -jakarta
> * multiple fields: title:lucene author:hatcher
>
> Main additions in SpanQueryParser syntax vs. classic syntax:
> * Can require "in order" for phrases with slop with the \~> operator:
> "jakarta apache"\~>3
> * Can specify "not near": "fever bieber"!\~3,10 ::
> find "fever" but not if "bieber" appears within 3 words before or 10
> words after it.
> * Fully recursive phrasal queries with \[ and \]; as in: \[\[jakarta
> apache\]~3 lucene\]\~>4 ::
> find "jakarta" within 3 words of "apache", and that hit has to be within
> four words before "lucene"
> * Can also use \[\] for single level phrasal queries instead of " as in:
> \[jakarta apache\]
> * Can use "or grouping" clauses in phrasal queries: "apache (lucene solr)"\~3
> :: find "apache" and then either "lucene" or "solr" within three words.
> * Can use multiterms in phrasal queries: "jakarta\~1 ap*che"\~2
> * Did I mention full recursion: \[\[jakarta\~1 ap*che\]\~2 (solr~
> /l\[ou\]\+\[cs\]\[en\]\+/)]\~10 :: Find something like "jakarta" within two
> words of "ap*che" and that hit has to be within ten words of something like
> "solr" or that "lucene" regex.
> * Can require at least x number of hits at boolean level: "apache AND (lucene
> solr tika)~2
> * Can use negative only query: -jakarta :: Find all docs that don't contain
> "jakarta"
> * Can use an edit distance > 2 for fuzzy query via SlowFuzzyQuery (beware of
> potential performance issues!).
> Trivial additions:
> * Can specify prefix length in fuzzy queries: jakarta~1,2 (edit distance =1,
> prefix =2)
> * Can specifiy Optimal String Alignment (OSA) vs Levenshtein for distance
> <=2: (jakarta~1 (OSA) vs jakarta~>1(Levenshtein)
> This parser can be very useful for concordance tasks (see also LUCENE-5317
> and LUCENE-5318) and for analytical search.
> Until LUCENE-2878 is closed, this might have a use for fans of SpanQuery.
> Most of the documentation is in the javadoc for SpanQueryParser.
> Any and all feedback is welcome. Thank you.
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