aws/aws-sdk-ruby — pull request #126 by jagthedrummer (2013-01-16 23:59:40+00:00)
Title: Jeremy/validates uniqueness of

Added a validation for uniqueness. This allows the following functionality.

````ruby
class Book < AWS::Record::Model
string_attr :title
validates_uniqueness_of :title
end

book1 = Book.new(:title => "The big book of tests")
book1.valid? # => true
book1.save

book2 = Book.new(:title => "The big book of tests")
book2.valid? # => false
````