--- On Mon, 9/14/09, Paul Forsyth <p...@ez.no> wrote:
> From: Paul Forsyth <p...@ez.no>
> Subject: Re: Searching for the '+' character
> To: solr-user@lucene.apache.org
> Date: Monday, September 14, 2009, 5:55 PM
> With words like 'product+' i'd expect
> a search for '+' to return results like any other character
> or word, so '+' would be found within 'product+' or similar
> text.
>
> I've tried removing the worddelimiter from the query
> analyzer, restarting and reindexing but i get the same
> result. Nothing is found. I assume one of the filters could
> be adjusted to keep the '+'.
>
> Weird thing is that i tried to remove all filters from the
> analyzer and i get the same result.
>
> Paul
When you remove all filters '+' is kept, but still '+' won't match 'product+'.
Because you want to search inside a token.
If + sign is always at the end of of your text, and you want to search only
last character of your text EdgeNGramFilterFactory can do that.
with the settings side="back" maxGramSize="1" minGramSize="1"
The fieldType below will match '+' to 'product+'
<fieldType name="textx" class="solr.TextField" positionIncrementGap="100">
<analyzer type="index">
<tokenizer class="solr.HTMLStripWhitespaceTokenizerFactory"/>
<filter class="solr.LowerCaseFilterFactory"/>
<filter class="ISOLatin1AccentFilterFactory"/>
<filter class="solr.SnowballPorterFilterFactory" language="English"/>
<filter class="solr.EdgeNGramFilterFactory" side="back" maxGramSize="1"
minGramSize="1"/>
</analyzer>
<analyzer type="query">
<tokenizer class="solr.WhitespaceTokenizerFactory"/>
<filter class="solr.SynonymFilterFactory" synonyms="synonyms.txt"
ignoreCase="true" expand="true"/>
<filter class="solr.LowerCaseFilterFactory"/>
<filter class="ISOLatin1AccentFilterFactory"/>
<filter class="solr.SnowballPorterFilterFactory" language="English"/>
</analyzer>
</fieldType>
But this time 'product+' will be reduced to only '+'. You won't be able to
search it otherways for example product*. Along with the last character, if you
want to keep the original word it self you can set maxGramSize to 512. By doing
this token 'product+' will produce 8 tokens: (and query product* or product+
will return it )
+ word
t+ word
ct+ word
uct+ word
duct+ word
oduct+ word
roduct+ word
product+ word
If + sign can be anywhere inside the text you can use NGramTokenFilter.
Hope this helps.
