transactions in ruby

# in the console ...

def try_to_fail(p)
  begin
    MyModel.transaction do
      p.name = "Eustace"
      p.save
      5+5
      raise Exception
    end
  rescue Exception
    puts "not saved"
  end
end

>> p = MyModel.new
>> try_to_fail(p)
not saved
=> nil
>> p
=> #<MyModel id: 1784, name: "Eustace", number: nil, type: nil>

def try_to_fail_without_begin_block(p)
	  Pin.transaction do
	      p.name = "harold"
		  p.save
		  5+5
		  raise Exception
	  end
end

>> p = Pin.new
>> try_to_fail_without_begin_block(p)
=> Exception raised ... with traceback
>> p
=> #<MyModel id: 1784, name: "Eustace", number: nil, type: nil>