Context: How does an order saving work?
958164/app/code/Magento/Sales/Model/ResourceModel/Order.php#L139-L165
/**
* @param \Magento\Framework\Model\AbstractModel $object
* @return $this
*/
protected function _beforeSave(\Magento\Framework\Model\AbstractModel $object)
{
if (!$object->getId()) {
/** @var \Magento\Store\Model\Store $store */
$store = $object->getStore();
$name = [
$store->getWebsite()->getName(),
$store->getGroup()->getName(),
$store->getName(),
];
$object->setStoreName(implode(PHP_EOL, $name));
$object->setTotalItemCount($this->calculateItems($object));
}
$object->setData(
'protect_code',
substr(md5(uniqid(Random::getRandomNumber(), true) . ':' . microtime(true)), 5, 6)
);
$isNewCustomer = !$object->getCustomerId() || $object->getCustomerId() === true;
if ($isNewCustomer && $object->getCustomer()) {
$object->setCustomerId($object->getCustomer()->getId());
}
return parent::_beforeSave($object);
}