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https://issues.apache.org/jira/browse/LUCENE-2458?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12891945#action_12891945
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Uwe Schindler commented on LUCENE-2458:
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QP has now a public final void setAutoGeneratePhraseQueries(boolean value). The
default value is the one coming from Version parameter, but you can easily
change it (like e.g. me, often working with such type of product numbers but
never CJK text) can easily use this behaviour. Lucene's problem is, that it
does not take position for scoring into account, so documents where the tokens
appear next to each other do not score higher (in contract to google, which
supports those combined tokens).
> queryparser makes all CJK queries phrase queries regardless of analyzer
> -----------------------------------------------------------------------
>
> Key: LUCENE-2458
> URL: https://issues.apache.org/jira/browse/LUCENE-2458
> Project: Lucene - Java
> Issue Type: Bug
> Components: QueryParser
> Reporter: Robert Muir
> Assignee: Robert Muir
> Priority: Blocker
> Fix For: 3.1, 4.0
>
> Attachments: LUCENE-2458.patch, LUCENE-2458.patch, LUCENE-2458.patch,
> LUCENE-2458.patch
>
>
> The queryparser automatically makes *ALL* CJK, Thai, Lao, Myanmar, Tibetan,
> ... queries into phrase queries, even though you didn't ask for one, and
> there isn't a way to turn this off.
> This completely breaks lucene for these languages, as it treats all queries
> like 'grep'.
> Example: if you query for f:abcd with standardanalyzer, where a,b,c,d are
> chinese characters, you get a phrasequery of "a b c d". if you use cjk
> analyzer, its no better, its a phrasequery of "ab bc cd", and if you use
> smartchinese analyzer, you get a phrasequery like "ab cd". But the user
> didn't ask for one, and they cannot turn it off.
> The reason is that the code to form phrase queries is not internationally
> appropriate and assumes whitespace tokenization. If more than one token comes
> out of whitespace delimited text, its automatically a phrase query no matter
> what.
> The proposed patch fixes the core queryparser (with all backwards compat
> kept) to only form phrase queries when the double quote operator is used.
> Implementing subclasses can always extend the QP and auto-generate whatever
> kind of queries they want that might completely break search for languages
> they don't care about, but core general-purpose QPs should be language
> independent.
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