docbrown/db/migrate/20200120053525_add_banished_users_table.rb

class AddBanishedUsersTable < ActiveRecord::Migration[5.2]
  def change
    create_table :banished_users do |t|
      t.string :username
      t.index :username, unique: true
      t.references :banished_by

      t.timestamps
    end
  end
end