protected function _prepareCollection()
{
$collection = Mage::getResourceModel($this->_getCollectionClass());
$collection->getSelect()->join('sales_flat_order_address', 'main_table.entity_id = sales_flat_order_address.parent_id',array('company'));
$this->setCollection($collection);
}
我使用上面的代码在订单列表网格上添加公司字段。但它显示“具有相同 ID“1038”的项目(Mage_Sales_Model_Order)已经存在”