title: Does AppEngine HR Datastore auto assign negative IDs?
body: <p>I am using AppEngine with the HR Datastore and my Objects have IDs of type <code>Long</code> (using Java). I do not set the ID myself but let the Datastore choose a new unique one. So far I have only seen positive IDs generated.</p>
  
  <p>Does AppEngine also assign negative IDs ever? (assuming that I do not request more than 2^63 IDs of course ;-)) </p>