嵌套查询/导航属性集合 [英] Nested query/Navigation Property collection

问题描述

假设以下模型：（示例来自Breeze DocCode）

Assume the following models: (example taken from Breeze DocCode)

public class Customer {

    public Guid CustomerID { get; internal set; }
    public ICollection<Order> Orders { get; set; }
}

public class SomeDetail{
    public string name{ get; set; }
}

public class Order {

    public int OrderID {get; set;}
    public Guid? CustomerID {get; set;}

    public SomeDetail detail {get; set;}
}

针对单个导航属性的嵌套查询对我来说很清楚。如果Navigation属性是一个集合，该怎么办？像这样的东西：

Nested queries against single Navigation Properties are clear to me. How could this be done if the Navigation Property is a collection? Something like this:

var query = EntityQuery.from("Customers")
                 .where("Orders.detail.name", "==", someName);

作为文本：
选择所有客户的订单详细信息名称

As "Text": Select all Customers where the name of the detail of any order this customer has equals someCondition?

我在这里遇到错误，因为

I am running into errors here because

.where("Orders.detail.name, "=", someCondition)

是不可能的
是否有一种简短的方法来检查这种情况，而又无需增加收款额和每手过滤数量？

is not possible due to the collection. Is there a short way to check for this conditions without building up a number off collections and filtering per hand?

任何帮助都值得赞赏

推荐答案

从Breeze 1.4.6开始，我们添加了对两个新查询运算符的支持： any和 all

As of Breeze 1.4.6, we have added support for two new query operators: "any" and "all"

这意味着您的查询现在可以看起来像这样。

This means that your query can now look something like this.

var query = EntityQuery.from("Customers")
   .where("Orders", "any", "detail.name", "==", someName);

请参阅： http：/ /www.breezejs.com/documentation/query-examples

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