Magento - Delete order (place this in index.php and add id(s))

order_delete.php

<?php

// src : https://magento.stackexchange.com/a/21744/56191
// Thanks to Marius ;)

$orderIds = array (...);
$orders = Mage::getModel('sales/order')->getCollection()
    ->addFieldToFilter('entity_id', (array) $orderIds);
foreach ($orders as $o) {
    //load order object - I know it's not ok to use load in a loop but it should be ok since it's a one time script
    $order = Mage::getModel('sales/order')->load($o->getId());

    $invoices = $order->getInvoiceCollection();
    foreach ($invoices as $invoice){
        //delete all invoice items
        $items = $invoice->getAllItems();
        foreach ($items as $item) {
            $item->delete();
        }
        //delete invoice
        $invoice->delete();
    }
    $creditnotes = $order->getCreditmemosCollection();
    foreach ($creditnotes as $creditnote){
        //delete all creditnote items
        $items = $creditnote->getAllItems();
        foreach ($items as $item) {
            $item->delete();
        }
        //delete credit note
        $creditnote->delete();
    }
    $shipments = $order->getShipmentsCollection();
    foreach ($shipments as $shipment){
        //delete all shipment items
        $items = $shipment->getAllItems();
        foreach ($items as $item) {
            $item->delete();
        }
        //delete shipment
        $shipment->delete();
    }
    //delete all order items
    $items = $order->getAllItems();
    foreach ($items as $item) {
        $item->delete();
    }
    //delete payment - not sure about this one
    $order->getPayment()->delete();
    //delete quote - this can be skipped
    if ($order->getQuote()) {
        foreach ($order->getQuote()->getAllItems() as $item) {
            $item->delete();
        }
        $order->getQuote()->delete();
    }
    //delete order
    $order->delete();
}