需要设置：关联的引用选项：架构没有主键时的联系人

Question

我有以下架构：

  @primary_key false
  schema "companies" do
    field :number,         :integer, primary_key: true, read_after_writes: true
    field :name,           :string
    field :street,         :string
    has_many :contacts,    Busiket.Contact

    timestamps
  end


  schema "contacts" do

    field :firstname,     :string
    field :lastname,      :string

    belongs_to :company, Busiket.Company, foreign_key: :company, references: :number, type: :integer

    timestamps

  end

我有以下错误：

** (ArgumentError) need to set :references option for association :contacts when schema has no primary key
    lib/ecto/association.ex:329: Ecto.Association.Has.struct/3
    lib/ecto/schema.ex:1434: Ecto.Schema.association/5
    lib/ecto/schema.ex:1249: Ecto.Schema.__has_many__/4
    web/models/company.ex:18: (module)
    (stdlib) erl_eval.erl:670: :erl_eval.do_apply/6

迁移看起来：

create table(:companies, primary_key: false) do

  add :number,             :serial, primary_key: true
  add :name,               :string
  add :street,             :string
  add :zipcode,            :integer
  add :location,           :string
  add :phone,              :integer
  add :company_class,      references(:companies_classes, column: :code, type: :integer)
  add :country_iso,        references(:countries_codes, column: :iso, type: :string)
  add :email,              :string
  add :password_hash,      :string

  timestamps
end
execute "select setval(pg_get_serial_sequence('companies', 'number'), 999999)"
create unique_index(:companies, [:name, :email])

create table(:contacts) do

  add :firstname,      :string
  add :lastname,       :string
  add :title,          :string
  add :email,          :string
  add :password_hash,  :string

  add :company, references(:companies, column: :number, type: :integer, on_delete: :delete_all)

  timestamps
end
create unique_index(:contacts, [:email])

我做错了什么？