Comment 5 for bug 1519171

The issue here is cause that in model is used with_variant type [1] So, compare_type method see [2] and seems that it compares them as equal. This is the only case in Neutron, so there are no other places to fix this. I will propose patch for oslo.db, not sure that there is something that should be done on Neutron side.

[1] - https://github.com/openstack/neutron/blob/master/neutron/db/model_base.py#L100
[2] - http://paste.openstack.org/show/480278/