我使用mongo存储库从引用列表中检索值
以下是文档结构：

"order" :{
  "orderId": "OR1",
  "invoice": [
    {
      "refNo": "inv12",
      "amount": "3000.00"
    },
    {
      "refNo": "inv13",
      "amount": "3500.00"
    }
  ]
}

订单类

@Document(collection = "order")
public class Order{
    private String orderId;
    @DBRef 
    private List<Invoice> invoice;
}

发票类别

@Document(collection = "invoice")
public class Invoice {
    private String refNo;
    private BigDecimal amount;
}

我想按发票参考号检索订单，我尝试了下面显示的查询。

@Query("{'invoice': { $elemMatch: {'refNo': ?0 }} }")
List<Order> findOrdersByInvoice(String invoice);

这将产生一个空的结果集。有人能解释一下我哪里做错了吗？