[
https://issues.apache.org/jira/browse/LUCENE-5205?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14026947#comment-14026947
]
Paul Elschot commented on LUCENE-5205:
--------------------------------------
I'd like to extend this parser so it can be used to query positional joins,
LUCENE-5627. This parser is a good fit for that because it provides span
queries, and the positional joins are based on span queries, so integration
should be doable.
This needs two changes in the parser here, one for the label-fragment join, and
one for the label tree operations.
For the label-fragment join it would be necessary to allow a field in
AbstractSpanQueryParser._parsePureSpanClause, basically at the point where it
currently throws an exception "Can't process field ...". At that point a
positional join query can be inserted to join from the new field to the
original field of the span clause. This will have to be based on a field
schema that has the relations between the fields. This schema might also be
used for indexing the documents.
The label tree will need an extension here to provide span queries in a label
field that are based on the label tree info.
This is much the same as using the axes in XPath. I'd like to add the / for a
named child, .. for parent, // for descendant-or-self, and maybe some form of
child indexing.
It would be easier for me to try this from trunk rather than from the
lucene5205 branch.
> [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: 4.9
>
> 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_improve_stop_word_handling.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.
--
This message was sent by Atlassian JIRA
(v6.2#6252)
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org
For additional commands, e-mail: dev-h...@lucene.apache.org
