Does AppEngine HR Datastore auto assign negative IDs?

Question

I am using AppEngine with the HR Datastore and my Objects have IDs of type Long (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.

Does AppEngine also assign negative IDs ever? (assuming that I do not request more than 2^63 IDs of course ;-))

Answer 1

allocate_id_range (the Python method to preallocate ids) will throw an exception if you pass it negative values. So I guess that a negative id key is not a valid one.