akkoma/priv/repo/migrations/20170701142005_add_actor_index_to_activity.exs

defmodule Pleroma.Repo.Migrations.AddActorIndexToActivity do
  use Ecto.Migration

  def change do
    create_if_not_exists(
      index(:activities, ["(data->>'actor')", "inserted_at desc"], name: :activities_actor_index)
    )
  end
end