Streams: EctoMnesia does not support Ecto streams, and the custom EctoMnesia.Table.Stream uses records rather than structs

[Qqwy]

I wanted to use MyApp.Repo.stream to upgrade some rows in my tables to a format with new constraints (in this case: Giving all of them a UUID, since all newly-inserted models will have this UUID).

So MyApp.Repo.stream will raise an error, stating that EctoMnesia.Table.Stream.new should be used instead.

However:

1. This does not support queries, but only low-level table names.
2. This gives results in record-format, rather than as schema structs. AFAIK, there is no way that EctoMnesia exposes turning records to schema structs. I ended up performing an additional MyRepo.get!(NameOfModel, elem(record, 1)), but this is obviously a non-performant and hackish 'solution'.