Ahmet is correct: the porter stemmer assumes that your input is lower case,
so be sure to place the lower case filter before stemming.
BTW, this is the kind of detail that I have in my e-book:
http://www.lulu.com/us/en/shop/jack-krupansky/solr-4x-deep-dive-early-access-release-7/ebook/product-21203548.html
You could also find this detail down at the level of the Lucene Javadoc, but
IMHO it's inappropriate to expect Solr users to have to dive down into
Lucene Javadoc.
See:
http://lucene.apache.org/core/4_9_0/analyzers-common/org/apache/lucene/analysis/en/PorterStemFilter.html
-- Jack Krupansky
-----Original Message-----
From: EXTERNAL Taminidi Ravi (ETI, Automotive-Service-Solutions)
Sent: Wednesday, July 9, 2014 4:03 PM
To: solr-user@lucene.apache.org ; Ahmet Arslan
Subject: RE: Lower/UpperCase Issue
Do I need to use different algorithm instead of porter stemming..? can you
suggest anything in you mind..?
-----Original Message-----
From: Ahmet Arslan [mailto:iori...@yahoo.com.INVALID]
Sent: Wednesday, July 09, 2014 12:26 PM
To: solr-user@lucene.apache.org
Subject: Re: Lower/UpperCase Issue
Hi,
Analysis admin page will tell you the truth. Just a guess: porter stem
filter could be "case sensitive" and that may cause the difference. I am
pretty sure porter stemming algorithms designed to work on lowercase input.
By the way you have two lowercase filters defined in index analyzer.
Ahmet
On Wednesday, July 9, 2014 7:18 PM, "EXTERNAL Taminidi Ravi (ETI,
Automotive-Service-Solutions)" <external.ravi.tamin...@us.bosch.com> wrote:
I have a situation here, when I search with "BALANCER" the results are
different Compare to "Balancer" and the order is different When I search
"BALANCER" then, the documents with Upper Case are first in the List and for
"Balancer" it is in different order.
I am confused why this behavior, Can some one has same issue or I am missing
something.
<fieldType name="text_general" class="solr.TextField"
positionIncrementGap="100">
<analyzer type="index">
<charFilter class="solr.HTMLStripCharFilterFactory" />
<tokenizer class="solr.StandardTokenizerFactory"/>
<filter class="solr.StopFilterFactory" ignoreCase="true"
words="stopwords.txt" />
<filter class="solr.PorterStemFilterFactory"/>
<filter class="solr.LowerCaseFilterFactory"/>
<filter class="solr.WordDelimiterFilterFactory"
generateWordParts="0" generateNumberParts="0" catenateWords="1"
catenateNumbers="1" catenateAll="0"/>
<filter class="solr.LowerCaseFilterFactory"/>
</analyzer>
<analyzer type="query">
<charFilter class="solr.HTMLStripCharFilterFactory" />
<tokenizer class="solr.StandardTokenizerFactory"/>
<filter class="solr.PorterStemFilterFactory"/>
<filter class="solr.StopFilterFactory" ignoreCase="true"
words="stopwords.txt" />
<filter class="solr.SynonymFilterFactory" synonyms="synonyms.txt"
ignoreCase="true" expand="true"/>
<filter class="solr.LowerCaseFilterFactory"/>
<filter class="solr.WordDelimiterFilterFactory"
generateWordParts="0" generateNumberParts="0" catenateWords="1"
catenateNumbers="1" catenateAll="0"/>
</analyzer>
</fieldType>
e.g query
http://localhost:8983/solr/Test/select?q=*%3A*&fq=Name%3ABALANCER&wt=json&indent=true
http://localhost:8983/solr/Test/select?q=*%3A*&fq=Name%3ABalancer&wt=json&indent=true
Thanks
Ravi
