Magento 1.7: Different sku and custom option sku for ERP System import

Question

The customer should get the sku of the product in the catalog, cart and checkout process to avoid missunderstanding as this standard sku is communicated in the price list, the custom options has no price difference as it handles technical features like country specific cables or different frequencies.

For the import to the erp system we need the custom option sku as it definies the product variant in the erp system.

Example: product sku ABC
custom option colour
blue sku ABC_00
red sku ABC_01

The object modell of the saved product should have the standard sku (ABC) and in the custom options the variant sku (ABC_01).

In our ERP System Navision the item (sku) has a standard number and optional variant codes.

Questioin: Which file / function defines the sku and the custom option sku?

Answer 1

\app\code\core\Mage\Catalog\Model\Product\Type\Abstract.php

function getSku(): sets the value for the product sku, in case an custom option sku exists it will add this value to the product sku separated with the default delimiter "-".
ABC-ABC_00

function getOptionSku(): sets the value for the custom_option->sku
ABC_00

We copied the file to local and changed the logic to our needs.