Saving custom data against a sales order item

Question

I am programatically saving orders. I need to be able to set a custom data for order items in sales_order_item table. What is the best way to do this?

I notice there is an additional_data column which looks ideal, however, I don't seem to be able to save data to it.

Code of what I've tried below...

$cartId = $this->cartManagementInterface->createEmptyCart();
$quote = $this->cartRepositoryInterface->get($cartId);
$product=$this->_product->load(1);
/**
 * Try to add the column here
 */
$product->setData('additional_data', json_encode(["ewfe" => 'wefwef']));
$quote->addProduct($product, 1);

// Set all shipping / customer details etc

$quote->getPayment()->importData(['method' => 'checkmo']);
$quote->save(); 
$quote->collectTotals();

// Create Order From Quote
$quote = $this->cartRepositoryInterface->get($quote->getId());
$orderId = $this->cartManagementInterface->placeOrder($quote->getId());

Running this saves the order, but does not add any data to the additional_data column.

Answer 1

For anyone interested, this is how I solved it...

$item = $quote->addProduct($product, 1);
$item->setAdditionalData('custom data');
$quote->save(); 

$quote->addProduct() returns a reference to the internal cart item.