Find active record query location

active_record_query_locator.rb

module ActiveRecord
  class QueryLocator
    def call(name, started, finished, unique_id, payload)
      # filter caller locations to application backtrace (filter all gem calls)
      # see http://ruby-doc.org/core-2.5.0/Kernel.html#method-i-caller_locations for more options
      caller_names = caller_locations.select { |line| line.to_s =~ /#{Rails.root.to_s}/ }
      # use the last caller in backtrace
      caller_name = caller_names.first

      Rails.logger.debug ["Notification:", name, started, finished, unique_id, caller_name, payload].join(" - ")
    end
  end
end

if Rails.configuration.active_record_query_locator
  Rails.logger.info "Registering ActiveRecord QueryLocator ..."
  ActiveSupport::Notifications.subscribe('sql.active_record', ActiveRecord::QueryLocator.new)
end

application.rb

# Add this to your application configuration in config/application.rb
# and / or config/environments/<RAILS ENV>.rb

# Activate active record query locator
config.active_record_query_locator = true

development.log

Notification: - sql.active_record - 2018-04-23 14:12:07 +0200 - 2018-04-23 14:12:07 +0200 - 192de139b90a62d66b18 - /path/to/rails/root/app/exporter/pdf_price.rb:149:in `price_info' - {:sql=>"SELECT \"calculations\".* FROM \"calculations\" WHERE \"calculations\".\"id\" = 1238", :name=>"Calculation Load", :binds=>[], :type_casted_binds=>[], :statement_name=>nil, :connection_id=>70109843746700}