Why Magento re-saves existing customer addresses during checkout?

Question

During the checkout process even if customer selects existing address form the drop-down the customer_address entity is being re-saved. Any idea what for?

Update:

It starts at Mage_Checkout_Model_Type_Onepage::saveOrder where the following code is executed:

$service = Mage::getModel('sales/service_quote', $this->getQuote());
$service->submitAll();

This submitAll calls Mage_Sales_Model_Service_Quote::submitOrder which executes the following:

$transaction->save();

This method loops through all objects of the quote(?) and saves them.

Update:

The most disgusting thing is that they are doing it for all addresses customer has. So if your visitor get 10 addresses saved in the address book all of them will be re-saved during checkout. Don't wonder why it is the most resource consuming part of Magento.

Answer 1

Usualy, unless data has changed on a model, calling save() on it will not cause the model to be re-saved.
This must have been the assumption during implementing the logic this way.

However, since the quote address model's method _beforeSave() sets the quote ID, the customer ID, plus possibly the customer address ID and the same_as_billing property via the _populateBeforeSaveData() method, the protection against unnecessary saving is circumvented.

An easy fix in the method populateBeforeSaveData() would be to check if the values about to be set on the address model already present on the current model with the same value.

Fortunately, quote addresses are stored in a flat table, which means the save is fairly efficient. And except for some B2B stores I haven't experienced customers having more then a couple of addresses.

Answer 2

I would hazard a guess that this was not thought through.

Maybe it was thought that rather than updating any new address plus any change in default billing and shipping address it would be easier just to save everything, since people wont have that many addresses and the checkout is already slow people wont notice....much.

Note: this is just an idea but I thought it worth sharing, also I can imagine myself making the same assumptions :(

Answer 3

address save during checkout is done by _afterSave()-Method in customer resource model.

protected function _afterSave(Varien_Object $customer)
{
    $this->_saveAddresses($customer);
    return parent::_afterSave($customer);
}

as i remember customer model get saved during order placement.

cheers