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Mongoid

Mongoid (pronounced mann-goyd) is an Object-Document-Mapper (ODM) for MongoDB written in Ruby. It was conceived in August, 2009 during a whiskey-induced evening at the infamous Oasis in Florida, USA by Durran Jordan.

The philosophy of Mongoid is to provide a familiar API to Ruby developers who have been using Active Record or Data Mapper, while leveraging the power of MongoDB's schemaless and performant document-based design, dynamic queries, and atomic modifier operations.

Sample Syntax

Mongoid supports MRI 1.9.3+, and JRuby 1.6.0+ in 1.9 mode. All code samples will use 1.9 syntax.

class Artist
  include Mongoid::Document
  field :name, type: String
  embeds_many :instruments
end

class Instrument
  include Mongoid::Document
  field :name, type: String
  embedded_in :artist
end

syd = Artist.where(name: "Syd Vicious").between(age: 18..25).first
syd.instruments.create(name: "Bass")
syd.with(database: "bands", session: "backup").save!