I am having an issue getting a custom model's value to update to NULL.
$model = Mage::getModel('custom/model')->load($id); $model->setCustomValue(NULL); $model->save();
This code does not update the field
custom_value in the database, and the database value accepts NULL values (Manually setting NULL in the database works fine).
As Tim mentions below using
Zend_Db_Expr("NULL") does set the value to null, could anyone explain why this is required in Magento and not just simply a php