Ecto migration, custom ID name and type to autogenerate/autoincrement integer in mssql

Use type serial to make a column type int that autoincrements in SQL Server.

The default type for id is bigserial and creates a PK type of bigint.

defmodule MyApp.Repo.Migrations.CreatePosts do
  use Ecto.Migration

  def change do
    create table("Post", primary_key: [name: :ID, type: :serial]) do
      add :Name, :string, null: false
      add :Description, :string
      timestamps()
    end

end

I posted this because bigserial and serial are not in the documents or guides for Ecto or Ecto SQL.