# File lib/data_objects/transaction.rb, line 27
    def initialize(uri, connection = nil)
      @connection = connection || DataObjects::Connection.new(uri)
      # PostgreSQL can't handle the full 64 bytes.  This should be enough for everyone.
      @id = Digest::SHA256.hexdigest("#{HOST}:#{$$}:#{Time.now.to_f}:#{@@counter += 1}")[0..-2]
    end