I'm trying to join between stackoverflow.com's dataset Posts and Users files and I'm having trouble. I want to add the user profile of the question poster to a Post.
Do I use User.AccountId or User.Id? Do I use Posts.OwnerUserId? Neither seems to work. I get no hits. I'm using the 2019-08-05 dataset. The semantics are never explained anywhere. I think AccountId is the global user ID and the UserId is the per-site ID. But still I get no hits.