Update products programmatically in Magento

Question

I\'m working on a script that will create or update products in my catalog.
The script works fine when the product needs to be created, but it fails when the product alr

Answer 1

Adding Mage::app()->setCurrentStore(Mage_Core_Model_App::ADMIN_STORE_ID); before saving product solves the error. The sample code below updates product's cost.

Mage::app()->setCurrentStore(Mage_Core_Model_App::ADMIN_STORE_ID);
$productId = 160;
$newCost = 80;
$product = Mage::getModel('catalog/product')->load($productId);
$product->setCost($newCost)->save();