如何在Ecto查询中使用异或(XOR)，并在多对多关系中按ID过滤？

defmodule MyApp.User do
  use Ecto.Schema

  schema "users" do
    field :name, :string
    has_many :user_roles, MyApp.UserRole
    many_to_many :roles, MyApp.Role, join_through: MyApp.UserRole
  end
end

defmodule MyApp.Role do
  use Ecto.Schema

  schema "roles" do
    field :name, :string
    many_to_many :users, MyApp.User, join_through: MyApp.UserRole
  end
end

defmodule MyApp.UserRole do
  use Ecto.Schema

  schema "user_roles" do
    belongs_to :user, MyApp.User
    belongs_to :role, MyApp.Role
  end
end

defmodule MyApp.UserQuery do
  def filter_users_with_xor(ids) do
    query =
      from u in MyApp.User,
        join: ur in assoc(u, :user_roles),
        join: r in assoc(ur, :role),
        where: xor(u.name == "Alice", r.id in ^ids)

    MyApp.Repo.all(query)
  end
end