def show
      @field_value_report = Krikri::FieldValueReport.find(params[:id], 
                                                          params[:provider_id])

      respond_to do |format|
        format.csv
      end
    end
def show
      @field_value_report = Krikri::FieldValueReport.find(params[:id], 
                                                          params[:provider_id])

      respond_to do |format|
        format.csv
      end
    end
Renders the show view for the field value report, given by a compound key.
 The compound key is comprised by the field value report's field
 (represented by the route's id param) and the provider's id.