After "mix phx.gen.json BiddingRounds BiddingRound bidding_rounds round_number:integer running:boolean --no-scope".

lib/beet_round_server/bidding_rounds/bidding_round.ex

@@ -0,0 +1,20 @@
+defmodule BeetRoundServer.BiddingRounds.BiddingRound do
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  @primary_key {:id, :binary_id, autogenerate: true}
+  @foreign_key_type :binary_id
+  schema "bidding_rounds" do
+    field :round_number, :integer
+    field :running, :boolean, default: false
+
+    timestamps(type: :utc_datetime)
+  end
+
+  @doc false
+  def changeset(bidding_round, attrs) do
+    bidding_round
+    |> cast(attrs, [:round_number, :running])
+    |> validate_required([:round_number, :running])
+  end
+end