c# - 如何使用 C# 和 MongoDB 'AND' 多个 $elemMatch 子句？

Question

我将 10Gen 认可的 c# 驱动程序用于 mongoDB 用于 c# 应用程序和数据浏览，我正在使用 Mongovue。

以下是两个示例文档架构:

{
  "_id": {
    "$oid": "4ded270ab29e220de8935c7b"
  },
  "Relationships": [
    {
      "RelationshipType": "Person",
      "Attributes": {        
        "FirstName": "Travis",
        "LastName": "Stafford"
      }
    },
    {
      "RelationshipType": "Student",
      "Attributes": {
        "GradMonth": "",
        "GradYear": "",
        "Institution": "Test1",
      }
    },
    {
      "RelationshipType": "Staff",
      "Attributes": {
        "Department": "LIS",
        "OfficeNumber": "12",
        "Institution": "Test2",
      }
    }
  ]
},    

{
  "_id": {
    "$oid": "747ecc1dc1a79abf6f37fe8a"
  },
  "Relationships": [
    {
      "RelationshipType": "Person",
      "Attributes": {        
        "FirstName": "John",
        "LastName": "Doe"
      }
    },
    {
      "RelationshipType": "Staff",
      "Attributes": {
        "Department": "Dining",
        "OfficeNumber": "1",
        "Institution": "Test2",
      }
    }
  ]
}

我需要一个查询来确保满足两个 $elemMatch 条件，以便我可以匹配第一个文档，但不能匹配第二个文档。以下查询在 Mongovue 中有效。

{
  'Relationships': { $all: [
        {$elemMatch: {'RelationshipType':'Student', 'Attributes.Institution': 'Test1'}},
        {$elemMatch: {'RelationshipType':'Staff', 'Attributes.Institution': 'Test2'}}
     ]}
}

如何在我的 c# 代码中执行相同的查询？

Answer 1

无法使用 c# 驱动程序构建上述查询(至少在 1.0 版中)。

但是您可以构建另一个更清晰的查询，它会返回相同的结果:

{ "Relationships" : 
          { "$elemMatch" : 
              { "RelationshipType" : "Test", 
                "Attributes.Institution" : { "$all" : ["Location1", "Location2"] } 
              } 
          } 
}

还有来自 c# 的相同查询:

Query.ElemMatch("Relationships", 
    Query.And(
        Query.EQ("RelationshipType", "Test"),
            Query.All("Attributes.Institution", "Location1", "Location2")));