```ruby
class CreateGroups < ActiveRecord::Migration
  def change
    create_table :groups do |t|
      t.string :name, null: false
      t.string :address, null: false

      t.timestamps null: false
    end
  end
end
```

Change groups migration so that the attributes we expect are saved.
user
```ruby
class CreateGroups < ActiveRecord::Migration
  def change
    create_table :groups do |t|
      t.integer :number,   null: false
      t.string  :street,   null: false
      t.string  :city,     null: false
      t.integer :zip_code, null: false

      t.timestamps null: false
    end
  end
end
```
assistant