Code review comment for lp:~wgrant/launchpad/observer-db

Oh, and
+COMMENT ON COLUMN AccessPolicyArtifact.policy IS 'An optional policy that controls access to this artifact. Otherwise the artifact is public.';

Do we want APA rows for public artifacts at all? Or are we treating bug/branch.policy as a denormalisation [put another way - which side is authoritative if we are doing data repair in the future]. I would have expected 'public bugs have no APA rows'.