How to update records in intermediate table if data has changed?

Question

Laravel

On the checkout page - I create an order and write the data from the basket into it, write it in a loop

foreach ( $items_cart as $item ) {
    //запись связанных данных в промежуточную таблицу
    $order->product()->attach([ $item['item_id']=>[ 'product_quantity'=>$item['quantity'],'product_color'=>$item['color'] ] ]);
}

But let's say the user decided to return to put something else in the basket, and delete something. So when I return to the checkout page, I need to make changes - delete something that is no longer in the basket and add a new one. And if there are no changes, leave it as is. Can this be done and how?

Answer 1

There are 2 ways, simple and dreary.
An easy way is to delete the old data from the trash every time and write new ones.
The tedious way is a combination of array_diff functions to find out which products to add and which to remove

$attached = array_diff($new, $old);
 $deleted = array_diff($old, $new);

Answer 2

laravel has a great sync method. I recommend that you carefully read the documentation before asking such questions.
Search (ctrl + f) for the word sync(