bench for MongoDB vs PostgreSQL.rb

require 'rubygems'

######################################################################
### ActiveRecord (PostgreSQL)

require 'active_record'
ActiveRecord::Base.establish_connection(:adapter=>"postgresql", :database=>"jpop", :user=>"maiha")
module PG
  class Song < ActiveRecord::Base
    # Indexes: "index_songs_singer" btree (singer)
  end
end
# p PG::Song.count # => 64482

######################################################################
### MongoRecord (MongoDB)

require 'mongo'
require 'mongo_record'
MongoRecord::Base.connection = XGen::Mongo::Driver::Mongo.new.db('jpop')
module MD
  class Song < MongoRecord::Base
    collection_name :songs
    fields :code, :name, :singer, :word, :music, :intro, :tieup, :body, :created_at
    index :singer
  end
end
# p MD::Song.count # => 64482

######################################################################
### Bench

require 'rbench'

puts "Bench1: counting records using index"
[10,100,1000].each do |times|
  puts "#{times} times:"
  RBench.run(times) do
    report("PostgreSQL") { PG::Song.count({:conditions => {:singer => "℃-ute" }}) } # matches 19
    report("MongoDB"   ) { MD::Song.count({:conditions => {:singer => "℃-ute" }}) } # matches 19
  end
  puts ""
end

puts "Bench2: counting records using seq scan"
[1,10,100].each do |times|
  puts "#{times} times:"
  RBench.run(times) do
    report("PostgreSQL") { PG::Song.count(:conditions => {:body => "LOVE"}) } # matches 0
    report("MongoDB"   ) { MD::Song.count(:conditions => {:body => "LOVE"}) } # matches 0
  end
  puts ""
end

__END__

Bench1: counting records using index
10 times:
                   Results |
----------------------------
PostgreSQL           0.028 |
MongoDB              0.012 |

100 times:
                   Results |
----------------------------
PostgreSQL           0.080 |
MongoDB              0.126 |

1000 times:
                   Results |
----------------------------
PostgreSQL           0.732 |
MongoDB              1.157 |

Bench2: counting records using seq scan
1 times:
                   Results |
----------------------------
PostgreSQL           0.304 |
MongoDB              0.063 |

10 times:
                   Results |
----------------------------
PostgreSQL           1.621 |
MongoDB              0.600 |

100 times:
                   Results |
----------------------------
PostgreSQL          16.485 |
MongoDB              5.198 |