Description
Common usecase is to want to search on the number of values in a multivalued field.
we should add a FieldMutationUpdateProcessorFactory that makes this easy...
<processor class="solr.CloneFieldUpdateProcessorFactory"> <str name="source">category</str> <str name="dest">number_of_categories_i</str> </processor> <processor class="solr.CountFieldValuesUpdateProcessorFactory"> <str name="fieldName">number_of_categories_i</str> </processor