Optimize School lookup by qualtrics code query

app/models/school.rb

@@ -15,7 +15,8 @@ class School < ApplicationRecord
 
   def self.find_by_district_code_and_school_code(district_code, school_code)
     School
-      .where(district: District.find_by_qualtrics_code(district_code))
+      .joins(:district)
+      .where(districts: {qualtrics_code: district_code})
       .find_by_qualtrics_code(school_code)
   end
 

app/services/survey_responses_data_loader.rb

@@ -36,7 +36,7 @@ class SurveyResponsesDataLoader
     return if school.nil?
 
     survey_items.each do |survey_item|
-      return unless SurveyItemResponse.where(response_id: response_id, survey_item: survey_item).empty?
+      return unless SurveyItemResponse.find_by(response_id: response_id, survey_item: survey_item).nil?
 
       likert_score = row[survey_item.survey_item_id]
       next if likert_score.nil?