You are viewing a plain text version of this content. The canonical link for it is here.
Posted to java-user@lucene.apache.org by Terry Steichen <te...@net-frame.com> on 2002/11/26 16:57:14 UTC
Does Escaping Really Work?
I'm confused about how to use escape characters in Lucene. My Lucene configuration is 1.3-dev1 and I use the StandardAnalyzer and QueryParser.
My documents have a field called 'path' with a value like "1102/a55407-2002nov2.xml". This field is indexed but not tokenized. Here are the various queries I've tried and their results:
1) When a dash is included in the query, Lucene interprets this as a space. ("path:1102/a55402-2002nov2.xml" is interpreted as "path:1102/a55402 -body:2002nov2.xml")
2) When a backslash is inserted before the dash (and the query does *not* contain a wildcard), Lucene interprets this by inserting a space in lieu of the next character. ('path:1102/a55402\-2002nov2.xml' interpreted as 'path:"1102/a55402 2002nov2.xml" [note the space where the dash was]')
3) When a backslash is inserted before the dash (and the query *does* contain a wildcard), Lucene interprets this literally, without any conversion. ("path:1102/55407\-2002nov*" is interpreted literally).
4) When a backslash is inserted before the dash and immediately followed by a wildcard, Lucene reports an error. ('path:1102/a55407-*' causes lexical error: Encountered <EOF> after :"")
My overall observation is that it appears it is not possible to escape a dash - is this true?
A previous post (yesterday) suggests that it is also not possible to escape a backslash. If that's also true, what characters can be escaped?
Regards,
Terry
Re: Does Escaping Really Work?
Posted by Terry Steichen <te...@net-frame.com>.
Well, pardon me for breathing, Otis.
I didn't make the connection (partly 'cause you changed the subject line).
But anyway, I don't understand your rather oblique answer - does escaping
work or not? Are you saying that, in order for it to work (the way the docs
say it does), I need to insert this module in the chain? Or what?
Terry
----- Original Message -----
From: "Otis Gospodnetic" <ot...@yahoo.com>
To: "Lucene Users List" <lu...@jakarta.apache.org>
Sent: Tuesday, November 26, 2002 3:07 PM
Subject: Re: Does Escaping Really Work?
> Didn't I just answer this last night?
> WhitespaceAnalyzer?
>
> Otis
>
> --- Terry Steichen <te...@net-frame.com> wrote:
> > I'm confused about how to use escape characters in Lucene. My Lucene
> > configuration is 1.3-dev1 and I use the StandardAnalyzer and
> > QueryParser.
> >
> > My documents have a field called 'path' with a value like
> > "1102/a55407-2002nov2.xml". This field is indexed but not tokenized.
> > Here are the various queries I've tried and their results:
> >
> > 1) When a dash is included in the query, Lucene interprets this as a
> > space. ("path:1102/a55402-2002nov2.xml" is interpreted as
> > "path:1102/a55402 -body:2002nov2.xml")
> >
> > 2) When a backslash is inserted before the dash (and the query does
> > *not* contain a wildcard), Lucene interprets this by inserting a
> > space in lieu of the next character.
> > ('path:1102/a55402\-2002nov2.xml' interpreted as 'path:"1102/a55402
> > 2002nov2.xml" [note the space where the dash was]')
> >
> > 3) When a backslash is inserted before the dash (and the query *does*
> > contain a wildcard), Lucene interprets this literally, without any
> > conversion. ("path:1102/55407\-2002nov*" is interpreted literally).
> >
> > 4) When a backslash is inserted before the dash and immediately
> > followed by a wildcard, Lucene reports an error.
> > ('path:1102/a55407-*' causes lexical error: Encountered <EOF>
> > after :"")
> >
> > My overall observation is that it appears it is not possible to
> > escape a dash - is this true?
> >
> > A previous post (yesterday) suggests that it is also not possible to
> > escape a backslash. If that's also true, what characters can be
> > escaped?
> >
> >
> > Regards,
> >
> > Terry
> >
> >
> >
> >
>
>
> __________________________________________________
> Do you Yahoo!?
> Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
> http://mailplus.yahoo.com
>
> --
> To unsubscribe, e-mail:
<ma...@jakarta.apache.org>
> For additional commands, e-mail:
<ma...@jakarta.apache.org>
>
>
--
To unsubscribe, e-mail: <ma...@jakarta.apache.org>
For additional commands, e-mail: <ma...@jakarta.apache.org>
Re: Does Escaping Really Work?
Posted by Otis Gospodnetic <ot...@yahoo.com>.
Didn't I just answer this last night?
WhitespaceAnalyzer?
Otis
--- Terry Steichen <te...@net-frame.com> wrote:
> I'm confused about how to use escape characters in Lucene. My Lucene
> configuration is 1.3-dev1 and I use the StandardAnalyzer and
> QueryParser.
>
> My documents have a field called 'path' with a value like
> "1102/a55407-2002nov2.xml". This field is indexed but not tokenized.
> Here are the various queries I've tried and their results:
>
> 1) When a dash is included in the query, Lucene interprets this as a
> space. ("path:1102/a55402-2002nov2.xml" is interpreted as
> "path:1102/a55402 -body:2002nov2.xml")
>
> 2) When a backslash is inserted before the dash (and the query does
> *not* contain a wildcard), Lucene interprets this by inserting a
> space in lieu of the next character.
> ('path:1102/a55402\-2002nov2.xml' interpreted as 'path:"1102/a55402
> 2002nov2.xml" [note the space where the dash was]')
>
> 3) When a backslash is inserted before the dash (and the query *does*
> contain a wildcard), Lucene interprets this literally, without any
> conversion. ("path:1102/55407\-2002nov*" is interpreted literally).
>
> 4) When a backslash is inserted before the dash and immediately
> followed by a wildcard, Lucene reports an error.
> ('path:1102/a55407-*' causes lexical error: Encountered <EOF>
> after :"")
>
> My overall observation is that it appears it is not possible to
> escape a dash - is this true?
>
> A previous post (yesterday) suggests that it is also not possible to
> escape a backslash. If that's also true, what characters can be
> escaped?
>
>
> Regards,
>
> Terry
>
>
>
>
__________________________________________________
Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
http://mailplus.yahoo.com
--
To unsubscribe, e-mail: <ma...@jakarta.apache.org>
For additional commands, e-mail: <ma...@jakarta.apache.org>