Solr - 如何按特定字段的值的频率排序？

Question

I'm working with Java and SolrJ on Eclipse. How can I sort the results of a SolrQuery by occurrency of values on a certain field? For example, when I search top n articles ( docType=0 ) of a particular author I want to sort query results by frequency of values in the journal_facet field (type String).

If a certain author X has written:

• 2 articles (a0, a1) in the journal named J0
• 3 articles (a2, a3, a4) in the journal named J1
• 1 article (a5) in the journal named J2

Order has to be a2, a3, a4, a0, a1, a5 and I want to show results in the following way

<doc>
 <arr name="author">
  <str>X</str>
 </arr>
 <str name="title">a2</str>
 <str name="journal">J1</str>
</doc>
<doc>
 <arr name="author">
  <str>X</str>
 </arr>
 <str name="title">a3</str>
 <str name="journal">J1</str>
</doc>
<doc>
 <arr name="author">
  <str>X</str>
 </arr>
 <str name="title">a4</str>
 <str name="journal">J1</str>
</doc>
<doc>
 <arr name="author">
  <str>X</str>
 </arr>
 <str name="title">a0</str>
 <str name="journal">J0</str>
</doc>
<doc>
 <arr name="author">
  <str>X</str>
 </arr>
 <str name="title">a1</str>
 <str name="journal">J0</str>
</doc>
<doc>
 <arr name="author">
  <str>X</str>
 </arr>
 <str name="title">a5</str>
 <str name="journal">J2</str>
</doc>

My query is

SolrServer solrServer = new HttpSolrServer(urlString);
SolrQuery query = new SolrQuery();
query.set("q", "docType:0);
query.set("fq", "author:X");
query.set("fl", "author, title, journal");
query.setRows(n);
...
QueryResponse response = solrServer.query(query);
SolrDocumentList results = response.getResults();

and in my Solr schema.xml there are the following fields and types

<types>
    ...
    <fieldType name="text_title" class="solr.TextField"
        positionIncrementGap="100">
        <analyzer type="index">
            <tokenizer class="solr.WhitespaceTokenizerFactory" />
            <charFilter class="solr.HTMLStripCharFilterFactory" />
            <filter class="solr.ASCIIFoldingFilterFactory" />
            <filter class="solr.WordDelimiterFilterFactory"
                generateWordParts="1" generateNumberParts="1" catenateWords="1"
                catenateNumbers="1" catenateAll="1" splitOnCaseChange="1"
                stemEnglishPossessive="1" preserveOriginal="1" />
            <filter class="solr.LowerCaseFilterFactory" />
            <filter class="solr.EdgeNGramFilterFactory" minGramSize="2" maxGramSize="15" side="front"/>
            <filter class="solr.KStemFilterFactory" />
            <filter class="solr.RemoveDuplicatesTokenFilterFactory" />
        </analyzer>
        <analyzer type="query">
            <tokenizer class="solr.WhitespaceTokenizerFactory" />
            <filter class="solr.ASCIIFoldingFilterFactory" />
            <filter class="solr.WordDelimiterFilterFactory"
                generateWordParts="1" generateNumberParts="1" catenateWords="0"
                catenateNumbers="0" catenateAll="0" splitOnCaseChange="1"
                stemEnglishPossessive="1" preserveOriginal="1" />
            <filter class="solr.LowerCaseFilterFactory" />
            <filter class="solr.KStemFilterFactory" />
            <filter class="solr.RemoveDuplicatesTokenFilterFactory" />
        </analyzer>
    </fieldType>

    <fieldType name="text_name" class="solr.TextField"
        positionIncrementGap="100">
        <analyzer type="index">
            <tokenizer class="solr.WhitespaceTokenizerFactory" />
            <charFilter class="solr.HTMLStripCharFilterFactory" />
            <filter class="solr.ASCIIFoldingFilterFactory" />
            <filter class="solr.WordDelimiterFilterFactory"
                generateWordParts="1" generateNumberParts="1" catenateWords="1"
                catenateNumbers="1" catenateAll="1" splitOnCaseChange="1" />
            <filter class="solr.LowerCaseFilterFactory" />
            <!-- n-grams utile per la ricerca per prefisso" -->
            <filter class="solr.EdgeNGramFilterFactory" minGramSize="2" maxGramSize="15" side="front"/>
            <!-- <filter class="solr.RemoveDuplicatesTokenFilterFactory"/> -->
        </analyzer>
        <analyzer type="query">
            <tokenizer class="solr.WhitespaceTokenizerFactory" />
            <filter class="solr.ASCIIFoldingFilterFactory" />
            <filter class="solr.WordDelimiterFilterFactory"
                generateWordParts="1" generateNumberParts="1" catenateWords="0"
                catenateNumbers="0" catenateAll="0" splitOnCaseChange="1" />
            <filter class="solr.LowerCaseFilterFactory" />
            <!-- <filter class="solr.RemoveDuplicatesTokenFilterFactory"/> -->
        </analyzer>
    </fieldType>
</types>
<fields>
    <field name="docType" type="tint" indexed="true" stored="true"
        multiValued="false" required="true" />
    <field name="key" type="string" indexed="true" stored="true"
        multiValued="false" required="true" />
    <field name="mdate" type="date" indexed="true" stored="true"
        multiValued="false" required="true" />
    ...
    <field name="author" type="text_name" indexed="true" stored="true"
        multiValued="true" />
    ...
    <field name="journal" type="text_title" indexed="true" stored="true"
        multiValued="false" />
    <field name="title" type="text_title" indexed="true" stored="true"
        multiValued="false" />
    ...
    <field name="journal_facet" type="string" indexed="true" stored="true"
        multiValued="false" />
    ...
    <copyField dest="journal_facet" source="journal" />
    ...
</fields>

Thanks a lot for your help.

Answer 1

What about writing custom function query and sorting by it:

http://localhost:8983/solr/select?q=*:*&sort=dist(2, point1, point2) desc

References

• Solr: Sort_by Function

Answer 2

If you facet your results, just use facet.sort to get facets sorted by frequency:

https://wiki.apache.org/solr/SimpleFacetParameters#facet.sort