Magento : sales_order_save_after gives memory allocation error

Question

I have created one observer and its called when order placed. sales_order_save_after. Also i have created one sales attribute and try to set value when order placed. but it gives memory allocation error.

Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 36 bytes) in D:\xammp\htdocs\magento-1.9.3.0\lib\Zend\Db\Statement\Pdo.php on line 228

Bellow is my code.

config.xml

<events>
      <sales_order_save_after> <!-- identifier of the event we want to catch -->
        <observers>
          <sales_order_save_after_handler> <!-- identifier of the event handler -->
            <type>model</type> <!-- class method call type; valid are model, object and singleton -->
            <class>customeraffiliate/observer</class> <!-- observers class alias -->
            <method>saveAffiliateId</method>  <!-- observer's method to be called -->
            <args></args> <!-- additional arguments passed to observer -->
          </sales_order_save_after_handler>
        </observers>
      </sales_order_save_after>
    </events>

Observer.php

class Looxis_Customeraffiliate_Model_Observer
{
    public function saveAffiliateId(Varien_Event_Observer $observer)
    {
        $order = $observer->getEvent()->getOrder();
        if($order->getId())
        {
            $orderModel = Mage::getModel('sales/order')->load($order->getId());
            //print_r($orderModel->getData());
            $orderModel->setAffiliateid(2);
            //print_r($orderModel->getData());die;
            $orderModel->save();
        }
    }       
}

Please help me why its give this error.

Answer 1

The event sales_order_save_after is called when save() function.

In your observer.. you have called the save() ($orderModel->save();) which is called sales_order_save_after again means there a recursive called happed at Observer that create memory issue

Use donot use load the order model again by

 $orderModel = Mage::getModel('sales/order')->load($order->getId());

Just change from

$order = $observer->getEvent()->getOrder();
        if($order->getId())
        {
            $orderModel = Mage::getModel('sales/order')->load($order->getId());
            //print_r($orderModel->getData());
            $orderModel->setAffiliateid(2);
            //print_r($orderModel->getData());die;
            $orderModel->save();
        }

to

$order = $observer->getEvent()->getOrder();
if($order->getId())
{
 $order->setAffiliateid(2);
    //print_r($orderModel->getData());die;
}