ActsAsBetterTree

acts_as_better_tree is great for anyone who needs a fast tree capable of handling millions of nodes without slowing down on writes like nestedset or on reads like a standard tree. It is backwards compatible with acts_as_tree and remains fast with large datasets by storing the ancestry of every node in the field csv_ids.

Installation

Add this line to your application's Gemfile:

gem 'acts_as_better_tree'

And then execute:

$ bundle

Or install it yourself as:

$ gem install acts_as_better_tree

Usage

Required fields are parent_id, root_id, csv_ids.

create_table :categories do |t|
 t.column :root_id, :integer
 t.column :parent_id, :integer
 t.column :csv_ids, :string
 t.column :name, :string
end

If upgrading from acts_as_tree just add root_id and csv_ids and run Category.build_csv_ids!

class Category < ActiveRecord::Base
    acts_as_better_tree :order => "name"
end

Example:
root
\_ child1
    \_ subchild1
    \_ subchild2

root      = Category.create("name" => "root")
child1    = root.children.create("name" => "child1")
subchild1 = child1.children.create("name" => "subchild1")

root.parent   # => nil
child1.parent # => root
root.children # => [child1]
root.children.first.children.first # => subchild1

Contributing

Fork it
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Added some feature')
Push to the branch (git push origin my-new-feature)
Create new Pull Request