Solr stopwords - documents do not match

Question

I am using solr-3.4, my part of the circuit looks like,

<fieldType name="text" class="solr.TextField" positionIncrementGap="100" autoGeneratePhraseQueries="true"> <analyzer type="index"> <tokenizer class="solr.WhitespaceTokenizerFactory"/> <filter class="solr.StopFilterFactory" ignoreCase="true" words="stopwords_en.txt" enablePositionIncrements="true"/> <filter class="solr.WordDelimiterFilterFactory" generateWordParts="1" generateNumberParts="1" catenateWords="1" catenateNumbers="1" catenateAll="0" splitOnCaseChange="1"/> <filter class="solr.LowerCaseFilterFactory"/> <filter class="solr.KeywordMarkerFilterFactory" protected="protwords.txt"/> <filter class="solr.PorterStemFilterFactory"/> </analyzer> <analyzer type="query"> <tokenizer class="solr.WhitespaceTokenizerFactory"/> <filter class="solr.SynonymFilterFactory" synonyms="synonyms.txt" ignoreCase="true" expand="true"/> <filter class="solr.StopFilterFactory" ignoreCase="true" words="stopwords_en.txt" enablePositionIncrements="true"/> <filter class="solr.WordDelimiterFilterFactory" generateWordParts="1" generateNumberParts="1" catenateWords="0" catenateNumbers="0" catenateAll="0" splitOnCaseChange="1"/> <filter class="solr.LowerCaseFilterFactory"/> <filter class="solr.KeywordMarkerFilterFactory" protected="protwords.txt"/> <filter class="solr.PorterStemFilterFactory"/> </analyzer> </fieldType> 

stopwords_en.txt contains


and
are
as

etc..

Now, when I search for “ buy a house ”, Solr does not return documents with the text “ buy a house ” to me.
Also, when I search for “ buy a house, ” Solr does not return documents with the text “ buy a house .”

DebugQuery part

 <str name="rawquerystring">cContent:"buy a house"</str> <str name="querystring">cContent:"buy a house"</str> <str name="parsedquery">PhraseQuery(cContent:"bui ? hous")</str> <str name="parsedquery_toString">cContent:"bui ? hous"</str> 

A similar (but not exact) question was found here
But there was no satisfactory answer to solve this problem.

Any idea how I can solve this problem? or what's wrong?

Answer 1

You are searching with PhraseQuery, so in the first case, "buy a house" will not match "buy a house." If you add slop (cContent: "buy house" ~ 2) to PhraseQuery, you will also get matches.

In the second case, although the stopwatch is being filtered out, he still expects that something will be in this position, so “buy a house” will correspond to “buy one house”, but not “buy a house”. Maybe slop can fix this too, but I'm not sure.

Answer 2

In fact, I think your problem with PorterStemmer is that the "house" is being transformed into a "house". If you really don’t think you need it, I would turn off the porter streamer. In my experience, this usually does more harm than good.