下面是我存储在 Azure MongoDB 中的 JSON 结构(粘贴了示例结构)，我想使用 Plyrs 中存在的 userID 元素进行查询( Sub Sub document) 以获取用户参加过的所有锦标赛的列表。

1. 我尝试过使用 Aggregate() 但没有成功。请纠正我 如果我遗漏了什么，下面是它的代码。

2. 尝试使用构建器但没有成功，使用构建器我能够检索到一个级别(子集合，json(粘贴在下面)引用高达 tbls )在那里我可以在 Plyrs(子子集合)上查询的任何方式。

3. Azure MongoDB 是否支持 Aggregate() 或不获取整个文档的计数？

请指导我聚合

   var count = sampleMongoDataBase.GetCollection<GameInfo>(sampleCollectionName).Aggregate()
                    .Unwind<GameInfo, TableDocumet>(t => t.Tables)
                    .Unwind<TableDocumet, PlayerDocument>(p => p.Players)
                   .Match(x => x.UserID == "3fd30fa8-f5c5-4311-8741-4032142bbb33")
                   .Group(new MongoDB.Bson.BsonDocument { { "id", "$Plyrs._id" }, { "count", new MongoDB.Bson.BsonDocument("$sum", 1) } }); 

build 者

 mongoDataBase.GetCollection<GameInfo>(mongoCollectionName).Find(Builders<GameInfo>.Filter.ElemMatch(x => x.Tables,t => t.TableId == 1)).Count();

错误: 命令聚合失败:不支持“$group”。

JSON:

`

{
"TnId": 651,
"QnId": "7a5de5dc-b02f-4013-9d02-ebf8430e7a56",
"samt": 10,
"tbls": [
  {
    "TblId": 1,
    "Plyrs": [
      {
        "_id": 1048995,
        "UserId": "FC381A6D717B6973-711BD743AE90E6D7",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Roman Yates",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1048996,
        "UserId": "fc3e0971-2c3c-e697-b68a-33b12a207bc2",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Neil Gaines",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1048997,
        "UserId": "FC369812-6DC04066-A133-1C10EEBA1546",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Lori Reyes",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1048998,
        "UserId": "FC2AC461-C7FAD800D3D79A2CD2680C72",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Duane Hoffman",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1048999,
        "UserId": "FC39AFCF-688C-B61A-A0DB-80EADAC832CD",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Alfredo Ware",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1049000,
        "UserId": "FC2B863D-9ACC-13C706EA-8E31917566DB",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Abigail Riddle",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      }
    ]
  },
  {
    "TblId": 2,
    "Plyrs": [
      {
        "_id": 1049001,
        "UserId": "FC2BCC93-DDAE-4622-8D1226BDF1181D63",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Rene Spence",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1049002,
        "UserId": "FC3D0CF42017-C3BFF460-E8DBDE3D1D77",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "TU006918",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1049003,
        "UserId": "FC2CDE495F34E557-77C8-4B10981B7758",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Marshall Lutz",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1049004,
        "UserId": "FC3EE1FDB4913FF345AE90CD14BE3607",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Roberto Burton",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1049005,
        "UserId": "FC378E3C-C2A0528F094A-7FB31BD9D278",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Summer Stephenson",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      },
      {
        "_id": 1049006,
        "UserId": "FC431BBB-A79D45A0EAB034676C755E5A",
        "St": 3,
        "PCS": 2,
        "ConnId": null,
        "DN": "Terence Fischer",
        "RB": 2,
        "LL": 1,
        "Chips": 5000,
        "Rank": 46,
        "ExitLvl": 0,
        "TRA": 0,
        "PRI": "",
        "IsAns": false
      }
    ]
  }

输出 : 例如，计数:5

最佳答案

并非所有 MongoDB 查询功能都出现在 Cosmos MongoDB API 中，目前聚合管道是未实现的功能之一。这就是为什么您收到错误说明 $group 不受支持的原因。

EDIT - As of November 2017, Aggregation Pipeline is now a supported operation with the MongoDB API of Cosmos DB. Full list of supported features is here.

一般聚合(sum、min、max、avg、count)已添加到 DocumentDB API。

您现在必须在 MongoDB API 中进行自己的聚合。

注意:支持 count()，因此假设您过滤数据(没有聚合管道)，您可以执行以下操作:

db.collection.find({...}).count()

同样，您可以通过排序执行 $min 或 $max。所以对于 $max，你可以做这样的事情来找到 foo 的最大值:

db.collection.find({...},{foo:1}).sort({foo:-1}).limit(1)

关于mongodb - Azure CosmosDB 使用 Mongo 驱动程序 : Get Count With out getting all documents based on element in sub sub document in C#.Net，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/44844678/