/home/komponen/public_html/oneclickcomponents/updateskus.php
<?php

include_once './app/Mage.php';
Mage::app()->setCurrentStore(Mage_Core_Model_App::ADMIN_STORE_ID);

$updates_file="./var/export/sku2sku.csv";
$sku_entry=array();
$updates_handle=fopen($updates_file, 'r');
if($updates_handle) {
while($sku_entry=fgetcsv($updates_handle, 1000, ",")) {
$old_sku=$sku_entry[0];
$new_sku=$sku_entry[1];
echo "<br>Updating ".$old_sku." to ".$new_sku." - ";
try {
$get_item = Mage::getModel('catalog/product')->loadByAttribute('sku', $old_sku);
if ($get_item) {
$get_item->setSku($new_sku)->save();
echo "successful";
} else {
echo "item not found";
}
} catch (Exception $e) {
echo "Cannot retrieve products from Magento: ".$e->getMessage()."<br>";
return;
}
}
}
fclose($updates_handle);
?>