MongoDB 的分组操作 In C#

C#对mongodb的分组查询操作，主要通过脚本或Aggregate方法来实现，以下通过一些实例作解析：

参考资料：http://www.tuicool.com/articles/2iqUZj

　　　　   http://www.cnblogs.com/vnii/archive/2012/08/23/2652891.html

　　　　   http://www.cnblogs.com/zhwl/archive/2013/12/19/3482140.html

1. 根据任务id进行分组，统计每个任务的浏览数量。

　　

        public static List<vm_quantityModel> GetMyIncomeDetail(int member_id, int pageIndex, int pageSize, out int totalCount)        {            //筛选条件            IMongoQuery query = Query.And(Query.EQ("member_id", member_id), Query.EQ("mark", 1));                        MongoCollection<BsonDocument> myCollection = MongoDBHelper.GetCollection("mstg_record_history");            //分组            Dictionary<string, int> dic_initial = new Dictionary<string, int>();            dic_initial["num"] = 0;            var r = myCollection.Group(                query,                "task_id", //分组的字段                BsonDocument.Create(dic_initial),                BsonJavaScript.Create("function(doc,prev){prev.num++;}"),                null            ).ToList();            List<vm_quantityModel> result = new List<vm_quantityModel>();            if (r != null && r.Count > 0)            {                foreach (var item in r)                {                    vm_quantityModel m = new vm_quantityModel();                    m.task_id = Common.StringHelper.StrToInt(item["task_id"].ToString());                    m.valid_count = Common.StringHelper.StrToLong(item["num"].ToString());                    result.Add(m);                }            }            totalCount = result.Count;            result = result.OrderByDescending(x => x.task_id).Skip((pageIndex - 1) * pageSize).Take(pageSize).ToList();            return result;        }

2.根据会员编号分组，累加价格的统计

        /// <summary>        /// 帮帮赚会员总收益        /// </summary>        /// <param name="memberIds"></param>        /// <returns></returns>        public static List<vm_rankingModel> GetBangZhuanList(List<int> memberIds)        {            var ids = memberIds.ConvertAll<BsonValue>(x => x);            //筛选字段            IMongoQuery query = Query.And(Query.In("member_id", ids), Query.EQ("mark", 1));            MongoCollection<BsonDocument> myCollection = MongoDBHelper.GetCollection("mstg_record_history");            //GroupBy的字段            GroupByBuilder groupbyBuilder = new GroupByBuilder(new string[] { "member_id" });            Dictionary<string, double> dic_M = new Dictionary<string, double>();            dic_M["msum"] = 0.0;            var result_M = myCollection.Group(query, groupbyBuilder, BsonDocument.Create(dic_M),                                            BsonJavaScript.Create("function(obj,prev){prev.msum += obj.price;}"),                                            BsonJavaScript.Create("function(obj){obj.sum=obj.msum;delete obj.sum;}")).ToList();            List<vm_rankingModel> result = new List<vm_rankingModel>();            if (result_M != null && result_M.Count > 0)            {                foreach (var item in result_M)                {                    double amount = Math.Round(Convert.ToDouble(item["msum"]), 2);                    result.Add(new vm_rankingModel                    {                        member_id = Common.StringHelper.StrToInt(item["member_id"].ToString()),                        amount = amount                    });                }            }                        result = result.OrderByDescending(x => x.amount).ToList();            return result;                    }

用Aggregate实现：

        public static List<vm_rankingModel> GetRankingList(int top)        {            MongoCollection<BsonDocument> myCollection = MongoDBHelper.GetCollection("mstg_record_history");            //分组获取金额总数            var group = new BsonDocument                 {                     { "$group",                         new BsonDocument                             {                                 { "_id", new BsonDocument                                              {                                                  {                                                      "MemberId","$member_id"                                                  }                                              }                                 },                                 {                                     "Count", new BsonDocument                                                  {                                                      {                                                          "$sum", "$price"                                                      }                                                  }                                 }                             }                   }                 };            //筛选条件            var match = new BsonDocument                 {                     {                         "$match",                         new BsonDocument                             {                                 {"mark", 1}                            }                     }                 };            var pipeline = new[] { match, group };            var list = myCollection.Aggregate(pipeline);            var matchingExamples = list.ResultDocuments            .Select(x => x.ToDynamic())            .ToList();            List<vm_rankingModel> result = new List<vm_rankingModel>();            //foreach (var example in matchingExamples)            //{            //    var message = string.Format("{0} - {1}", example._id.MyUser, example.Count);            //    Console.WriteLine(message);            //}            if (matchingExamples.Count > 0)            {                foreach (var example in matchingExamples)                {                    int member_id = Convert.ToInt32(example._id.MemberId.Value);                    double amount = Math.Round(example.Count.Value, 2);                    result.Add(new vm_rankingModel                    {                        member_id = member_id,                        amount = amount                    });                }            }                        result = result.OrderByDescending(x => x.amount).Take(top).ToList();            return result;        }

 

3. 按日期分组，累加价格的统计

        public static List<vm_bangzhuan_detailModel> GetBangZhuanDetails(List<int> memberIds)        {            var ids = memberIds.ConvertAll<BsonValue>(x => x);            //有效浏览数            IMongoQuery query = Query.And(Query.In("member_id", ids), Query.EQ("mark", 1));            MongoCollection<BsonDocument> myCollection = MongoDBHelper.GetCollection("mstg_record_history");                      Dictionary<string, double> dic_M = new Dictionary<string, double>();            dic_M["msum"] = 0.0;            var result_M = myCollection.Group(query, BsonJavaScript.Create("function(doc){  var date = new Date(doc.add_time); var dateKey = date.getFullYear()+'年'+(date.getMonth()+1)+'月'+date.getDate();  return {'day':dateKey}; }"), BsonDocument.Create(dic_M),                                            BsonJavaScript.Create("function(obj,prev){prev.msum += obj.price;}"),                                            BsonJavaScript.Create("function(obj){obj.sum=obj.msum;delete obj.sum;}")).ToList();            List<vm_bangzhuan_detailModel> result = new List<vm_bangzhuan_detailModel>();            if (result_M != null && result_M.Count > 0)            {                foreach (var item in result_M)                {                    double amount = Math.Round(Convert.ToDouble(item["msum"]), 2);                    result.Add(new vm_bangzhuan_detailModel                    {                           day = Convert.ToDateTime(item["day"]),                        amount = amount                    });                }            }            result = result.OrderByDescending(x => x.day).ToList();            return result;        }