Inspect db queries

inspect_queries.rb

# Make sure to have prepared statements enabled.
# config/database.yml
# test:
#  database: ...
#  prepared_statements: true

# Add this to the top scope of test/test_helper.rb or spec/rails_helper.rb and
# run tests as usual.

queries = Hash.new(0)

ActiveSupport::Notifications.subscribe("sql.active_record") do |*, payload|
  queries[payload[:sql]] += 1
end

at_exit do
  puts "Queries count = #{queries.values.sum}"

  queries = queries.sort_by { |k, v| -v }.to_h
  queries.each { |k, v| puts "#{v} | #{k}" }
end