Wildcard searching and highlighting with Solr 1.4

Question

Hey guys,

I've got a pretty much vanilla install of SOLR 1.4 apart from a few small config and schema changes.

<requestHandler name="standard" class="solr.SearchHandler" default="true">
    <!-- default values for query parameters -->
    <lst name="defaults">
        <str name="defType">dismax</str>
        <str name="echoParams">explicit</str>
        <str name="qf">
            text
        </str>
        <str name="spellcheck.dictionary">default</str>
        <str name="spellcheck.onlyMorePopular">false</str>
        <str name="spellcheck.extendedResults">false</str>
        <str name="spellcheck.count">1</str>
    </lst>
</requestHandler>

The main field type I'm using for Indexing is this:

<fieldType name="textNoHTML" class="solr.TextField" positionIncrementGap="100">
        <analyzer type="index">
            <charFilter class="solr.HTMLStripCharFilterFactory" />
            <tokenizer class="solr.WhitespaceTokenizerFactory"/>
            <filter class="solr.StopFilterFactory"
                    ignoreCase="true"
                    words="stopwords.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.SnowballPorterFilterFactory" language="English" protected="protwords.txt"/>
        </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.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.SnowballPorterFilterFactory" language="English" protected="protwords.txt"/>
        </analyzer>
    </fieldType>

now, when I perform a search using

"q=search+term&hl=on"

I get highlighting, and nice accurate scores.

BUT, for wildcard, I'm assuming you need to use "q.alt"? Is that true? If so my query looks like this:

"q.alt=search*&hl=on"

When I use the above query, highlighting doesn't work, and all the scores are "1.0".

What am I doing wrong? is what I want possible without bypassing some of the really cool SOLR optimizations.

cheers!

Answer 1

From what I know you can't use wildcards with the dismax handler, see http://wiki.apache.org/solr/DisMaxRequestHandler#q.

To simulate wildcard searching I used EdgeNGrams following some of the instructions here: http://www.lucidimagination.com/blog/2009/09/08/auto-suggest-from-popular-queries-using-edgengrams/. Actually I really only added the edgytext fieldtype to schema.xml and changed the fieldtype of the field I wanted to search.

Hope this helps!

Answer 2

Or you can grab the latest nightly build and use edismax (ExtendedDismaxQParser).

It handles both trailing and leading wildcards.

Answer 3

I share your opinion on the mailing list, so yeah maybe SO can serve as a place for Q&A regarding Solr.

I use http://lucene.472066.n3.nabble.com/ to search the different mailing lists with Solr relevant content.

Answer 4

I was really interested in using dismax with wildcard queries. Could someone please tell me when the next stable version of SOLR(like 1.4.2 or something) will be coming out with this feature.

Thanks.