Add a migration to remove embeded objects

priv/repo/migrations/20190418072951_remove_embeded_objects.exs

@@ -0,0 +1,10 @@
+defmodule Pleroma.Repo.Migrations.RemoveEmbededObjects do
+  use Ecto.Migration
+
+  # TODO: bench on a real DB and add clippy if it takes too long
+  def change do
+  execute """
+  update activities set data = jsonb_set(data, '{object}'::text[], data->'object'->'id') where data->>'type' = 'Create' and data->'object'->>'id' is not null;
+  """
+  end
+end