No Rails isso seria algo como
class ChangeStatusUpdatedAtToDateTime < ActiveRecord::Migration
def up
remove_column :bookings, :status_updated_at
add_column :bookings, :status_updated_at, :datetime
end
def down
remove_column :bookings, :status_updated_at
add_column :bookings, :status_updated_at, :time
end
end
Se você tiver dados que deseja transferir, poderá usar o seguinte código (não testado!):
class ChangeStatusUpdatedAtToDateTime < ActiveRecord::Migration
def up
add_column :bookings, :temp_status_updated_at, :datetime
Booking.update_all("temp_status_updated_at = updated_at")
remove_column :bookings, :status_updated_at
rename_column :bookings, :temp_status_updated_at, :status_updated_at
end
def down
add_column :bookings, :temp_status_updated_at, :time
Booking.update_all("temp_status_updated_at = updated_at")
remove_column :bookings, :status_updated_at
rename_column :bookings, :temp_status_updated_at, :status_updated_at
end
end