user

user.rb

# add_column :users, :data_key, :string
# add_column :users, :data_value, :string

  DATA_KEYS = ['vehicle_type', 'city', 'phone_model', 'availability', 'example_customer_service']

  DATA_KEYS.each do |method| 
    define_method(method) do
      find_by_data_key(method).try(:data_value)
    end

    # setter method
    define_method("#{method}=") do |value|
      data = find_or_initialize_by_data_key(method)
      data.data_value = value.strip
      data.save
    end
  end
  
  
  u= User.first
  u.city = "San Francisco"
NoMethodError: undefined method `find_or_initialize_by_data_key' for #<User:0x00000109a7da00>
  u.city= NoMethodError: undefined method `find_by_data_key' for #<User:0x00000109a7da00>