Simply add following to your gemfile

gem 'hstore-properties'

Create properties column in the model you would like to use properties within, i.e.

rails g migration AddPropertiesToUsers properties:hstore

Apply your migration

rake db:migrate

Finally, describe your properties in your model file

class User < ActiveRecord::Base
  include ActiveRecord::HstoreProperties
  properties 'third_name', 
             'some_cool_feature' => :boolean, 
             'comments' => :counter,
             'age' => :number


Retrieving values

By default, all your properties are of type String. There are number of other property types available though…

  • string
  • boolean
  • number
  • counter

More will come in near future…

All properties can be retrieved just as they are written into hstore column, by suffixing them with _property, i.e.

User.last.third_name_property #=> "Jack"

Boolean properties, can be additionaly retrieved by using _enabled? suffix, that will cast them to boolean value, i.e.

User.last.some_cool_feature_enabled? #=> true

Counter properties, can be retrieved by using _count suffix, that will cast them to integer value, i.e.

User.last.comments_count #=> 10

What is more, it is possible to bump counter properties, i.e. following line will increment comments property by 1


Updating through forms

You obviously need to add :properties to yours attr_accessible

Below is an example of building appropriate fields dynamically with formtastic

<%= semantic_form_for @user do |f| %>
    <%= f.first_name %>
    <%= f.fields_for :properties, OpenStruct.new(@user.properties) do |builder| %>
        <% User.properties.each do |property| %>
            <%= builder.input property.name, property.formtastic_options %>
        <% end %>
    <% end %>
    <%= f.submit %>
<% end %>

Further customization

If most of your properties are of the same type, but other than string, you can overwrite default_property_klass to make other type default, i.e.

class User < ActiveRecord::Base
  def self.default_property_klass

When to use?

  • If you consider adding redundant column to your table, that will only sometimes store any data
  • If you would like to make particular model “configurable”
  • If you will not likely perform queries on specific field but mostly read from it directly