如何查询嵌入数据documentDB以检索父文档

Question

在DocumentDb中，是否可以搜索子文档以获取父文档？

public class Customer
{
    [JsonProperty(PropertyName = "id")]
    public string Id { get; set; }

    [JsonProperty(PropertyName = "name")]
    public string Name { get; set; } 

    [JsonProperty(PropertyName = "locations")]
    public List<Location> Locations { get; set; }

    public Customer()
    {
        Locations = new List<Location>();
    }
}

public class Location
{
    [JsonProperty(PropertyName = "id")]
    public string Id { get; set; }

    [JsonProperty(PropertyName = "city")]
    public string City{ get; set; }

    [JsonProperty(PropertyName = "state")]
    public string State{ get; set; } 

}

在Document Explorer中，我可以看到我有这样一个类结构的实例：

{
  "id": "7",
  "name": "ACME Corp", 
  "location": [
    {
      "id": "c4202793-da55-4324-88c9-b9c9fe8f4b6c",
      "city": "newcity",
      "state": "ca" 
    }
  ]
},
{
  "id": "35",
  "name": "Another Corp", 
  "location": [
    {
      "id": "d33e793-da55-4324-88c9-b9c9fe8f4baa",
      "city": "newcity",
      "state": "ca" 
    }
  ]
}

有没有办法查询嵌入数据，例如city =＆＃39; newcity＆＃39;和州=＆＃39; ca＆＃39; 但检索父数据？如果我使用SelectMany（x =＆gt; x.Locations）来查询子项，那么它将获取位置数据而不是根（客户）文档。

感谢

Answer 1

  

有没有办法查询嵌入数据，例如city =＆＃39; newcity＆＃39;和州=＆＃39; ca＆＃39;但检索父数据？

是的，我们可以使用加入来执行此操作。更多详情请参阅Advanced database concepts and SQL queries。

df.groupby("id")["indicator"].fillna(value=None,method="ffill",limit=3) 

返回

C＃代码演示：

SELECT c.id as id ,c.name as name,l as location from customer c Join l in 
c.location where l.city = 'newcity' and l.state = 'ca'