akkoma/priv/repo/migrations/20180918182427_create_push_subscriptions.exs

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

  def change do
    create_if_not_exists table("push_subscriptions") do
      add :user_id, references("users", on_delete: :delete_all)
      add :token_id, references("oauth_tokens", on_delete: :delete_all)
      add :endpoint, :string
      add :key_p256dh, :string
      add :key_auth, :string
      add :data, :map

      timestamps()
    end

    create_if_not_exists index("push_subscriptions", [:user_id, :token_id], unique: true)
  end
end