Mysql 西蒙尼主义

你好，我正在使用symfony的条令，我想加入

$select ="SELECT c.sku, t.title, p.stock FROM BackendBundle:CartItems c 
                LEFT JOIN BackendBundle:PartInfo p ON p.nkrCode= c.sku
                LEFT JOIN BackendBundle:PartInfoTitles t ON t.internalCode = c.sku
                WHERE c.cart=".$cart;
                $em = $this->getDoctrine()->getManager();
                $query = $em->createQuery($select);
                $part = $query->getResult();

问题是c.cart是一个对象，因为它有一个外键。我如何使用这个原则来获取它

试试这个

$select ="SELECT c.sku, t.title, p.stock FROM BackendBundle:CartItems c 
                LEFT JOIN BackendBundle:PartInfo p ON p.nkrCode= c.sku
                LEFT JOIN BackendBundle:PartInfoTitles t ON t.internalCode = c.sku
                WHERE c.cart= :cart";
                $em = $this->getDoctrine()->getManager();
                $query = $em->createQuery($select)->setParameter('cart',$cart->getId());
                $part = $query->getResult();