Ruby 和 Neo4j 入門很簡單，只需要按照下面的步驟即可。

首先我們需要安裝 neography gem:

使用 Bundler

echo "source 'http://rubygems.org'
gem 'neography' " > Gemfile
bundle install 

不使用 Bundler

gem install neography

接下來我們添加任務到 Rakefile，下載 neo4j 并啟動：

echo "require 'neography/tasks'" >> Rakefile
rake neo4j:install
rake neo4j:start

一個圖數據庫能做什么呢？

做一個社交網絡的好友推薦如何？

require 'rubygems'
require 'neography'
 @neo = Neography::Rest.new

def create_person(name)
  @neo.create_node("name" => name)
end
def make_mutual_friends(node1, node2)
  @neo.create_relationship("friends", node1, node2)
  @neo.create_relationship("friends", node2, node1)
end
def suggestions_for(node)
  @neo.traverse(node,
                "nodes",
                {"order" => "breadth first",
                 "uniqueness" => "node global",
                 "relationships" => {"type"=> "friends",
                                     "direction" => "in"},
                 "return filter" => {"language" => "javascript",
                                     "body" => "position.length() == 2;"},
                 "depth" => 2}).map{|n| n["data"]["name"]}.join(', ')
end
johnathan = create_person('Johnathan')
mark      = create_person('Mark')
phil      = create_person('Phil')
mary      = create_person('Mary')
luke      = create_person('Luke')
make_mutual_friends(johnathan, mark)
make_mutual_friends(mark, mary)
make_mutual_friends(mark, phil)
make_mutual_friends(phil, mary)
make_mutual_friends(phil, luke)
puts "Johnathan should become friends with #{suggestions_for(johnathan)}"
RESULT
Johnathan should become friends with Mary, Phil</pre> 
 
我們來簡單的介紹一下上面的源碼：
 
我們需要引入 gems 并獲取一個連接到 Neo4j 服務器的 Neography 的實例：
 
require 'rubygems'
require 'neography'
 @neo = Neography::Rest.new
 
 然后編寫一個函數用于方便的創建節點并生成name屬性：
 
def create_person(name)
  @neo.create_node("name" => name)
end
 
 接下來創建另外一個函數用于關聯兩個節點。
 
在 Neo4j 中所有的關系都是有方向的，因此一個好友關系我們需要創建兩個關系：
 
def make_mutual_friends(node1, node2)
  @neo.create_relationship("friends", node1, node2)
  @neo.create_relationship("friends", node2, node1)
end
 
 
 
現在來到了最有趣的部分，我們為你推薦好友的好友。
 首先使用一個用戶作為一個起點，我們要返回該用戶的所有好友的好友：
def suggestions_for(node)
  @neo.traverse(node,
                "nodes",
                {"order" => "breadth first",
                 "uniqueness" => "node global",
                 "relationships" => {"type"=> "friends",
                                     "direction" => "in"},
                 "return filter" => {"language" => "javascript",
                                     "body" => "position.length() == 2;"},
                 "depth" => 2}).map{|n| n["data"]["name"]}.join(', ')
end
 
 通過創建一些簡單的數據來對這些代碼進行測試：
 
johnathan = create_person('Johnathan')
mark      = create_person('Mark')
phil      = create_person('Phil')
mary      = create_person('Mary')
luke      = create_person('Luke')

make_mutual_friends(johnathan, mark)
make_mutual_friends(mark, mary)
make_mutual_friends(mark, phil)
make_mutual_friends(phil, mary)
make_mutual_friends(phil, luke)

puts "Johnathan should become friends with #{suggestions_for(johnathan)}"

# RESULT
# Johnathan should become friends with Mary, Phil
 
 
 
怎樣，很簡單吧？
 
require 'rubygems'
require 'neography'

def create_person(name)
  Neography::Node.create("name" => name)
end

johnathan = create_person('Johnathan')
mark      = create_person('Mark')
phil      = create_person('Phil')
mary      = create_person('Mary')
luke      = create_person('Luke')

johnathan.both(:friends) << mark
mark.both(:friends) << mary
mark.both(:friends) << phil
phil.both(:friends) << mary
phil.both(:friends) << luke

def suggestions_for(node)
  node.incoming(:friends).
       order("breadth first").
       uniqueness("node global").
       filter("position.length() == 2;").
       depth(2).
       map{|n| n.name }.join(', ')
end
puts "Johnathan should become friends with #{suggestions_for(johnathan)}"


# RESULT
# Johnathan should become friends with Mary, Phil
 
 更多的信息請閱讀 Neography Documentation