How to count multi-valued Field in solr - solr

Question

I Want to count multi-valued field in SOLR.
I have two multi-valued fields store_id and filter_id
and i want to count these field value like
store_id = {0,3,7}
count_store_id = 3
filter_id = {12,13,20,22,59,61,62,145}
count_filter_id = 8
and is that possible when store_id is update then count_store_id also update in solr by default
## Ashraful Islam - As you told me i'll change it but there is nothing going happen here i attach image find it.

Answer 1

Yes as suggested by Alexandre Rafalovitch, by using defining custom UpdaterequestProcessor you can get the count value of multivalued field.
add below lines in your solrconfig.xml
<updateRequestProcessorChain name="multivaluecountnum" default="true">
<processor class="solr.CloneFieldUpdateProcessorFactory">
<str name="source">store_id</str>
<str name="dest">store_id_count</str>
</processor>
<processor class="solr.CloneFieldUpdateProcessorFactory">
<str name="source">filter_id</str>
<str name="dest">filter_id_count</str>
</processor>
<processor class="solr.CountFieldValuesUpdateProcessorFactory">
<str name="fieldName">store_id_count</str>
</processor>
<processor class="solr.CountFieldValuesUpdateProcessorFactory">
<str name="fieldName">filter_id_count</str>
</processor>
<processor class="solr.DefaultValueUpdateProcessorFactory">
<str name="fieldName">store_id_count</str>
<int name="value">0</int>
</processor>
<processor class="solr.DefaultValueUpdateProcessorFactory">
<str name="fieldName">filter_id_count</str>
<int name="value">0</int>
</processor>
<processor class="solr.LogUpdateProcessorFactory" />
<processor class="solr.RunUpdateProcessorFactory" />
</updateRequestProcessorChain>
Do not forget to add RunUpdateProcessorFactory at the end of any chains you define in solrconfig.xml
Add store_id_count and filter_id_count fields in schema file
<field name="store_id_count" type="int" stored="true"/>
<field name="filter_id_count" type="int" stored="true"/>
Reindex docs and query, you will see two new fields store_id_count and filter_id_count in result.
Hope this Helps,
Vinod.

Answer 2

You can do this with a custom UpdateRequestProcessor chain that uses CountFieldValuesUpdateProcessorFactory.