simple data

seeds.rb

require 'yaml'

yaml = YAML.load_file("#{Rails.root}/db/seeds.yml")

yaml.each do |model_str, data|
  model = model_str.capitalize.constantize
  data.each do |id, row|
    q = model.find_or_initialize_by id: id
    q.update row
  end
end

seeds.yml

Foo:
  1:
    foo: bar
  2:
    foo: baz
Bar:
  1:
    bar: baz