internal class Program7
    internal class Program7
    {
        public class Car
        {
            public string LicensePlate { get; set; }
            public CarType CarType { get; set; }
        }

        public enum CarType
        {
            Undefined = 0,
            Sport = 1,
            Suv = 2
        }

        internal static void Main2(string[] args)
        {
            foreach (var linqProvider in new []
                     {
                         LinqProvider.V2, 
                         LinqProvider.V3
                     })
            {
                var builder = new MongoUrlBuilder
                {
                    DatabaseName = "Sample",
                    Server = new MongoServerAddress("localhost", 27017)
                };
                var mongoClientSettings = MongoClientSettings.FromUrl(builder.ToMongoUrl());
                mongoClientSettings.LinqProvider = linqProvider;
                var mongoClient = new MongoClient(mongoClientSettings);
                var mongoDatabase = mongoClient.GetDatabase(builder.DatabaseName);

                var carsCollections = mongoDatabase.GetCollection<Car>("Cars");
                carsCollections.DeleteMany(c => true);
                carsCollections.InsertOne(new Car
                {
                    LicensePlate = "CAL-" + Guid.NewGuid().ToString().Substring(6),
                    CarType = CarType.Sport
                });

                var result = carsCollections.AsQueryable()
                    .GroupBy(c => 0)
                    .Select(g => new
                    {
                        SportCarCount = g.Sum(c => c.CarType == CarType.Sport ? 1 : 0),
                        SuvCarCount = g.Sum(c => c.CarType == CarType.Suv ? 1 : 0)
                    })
                    .FirstOrDefault();

                Console.WriteLine($"{linqProvider} - SportCarCount: {result.SportCarCount}");
                Console.WriteLine($"{linqProvider} - SuvCarCount: {result.SuvCarCount}");

                Console.WriteLine();
                Console.WriteLine();
            }
        }
    }

[{
        "$group": {
            "_id": 0,
            "__agg0": {
                "$sum": {
                    "$cond": [{
                            "$eq": [
                                "$CarType",
                                1
                            ]
                        },
                        1,
                        0
                    ]
                }
            },
            "__agg1": {
                "$sum": {
                    "$cond": [{
                            "$eq": [
                                "$CarType",
                                2
                            ]
                        },
                        1,
                        0
                    ]
                }
            }
        }
    }, {
        "$project": {
            "SportCarCount": "$__agg0",
            "SuvCarCount": "$__agg1",
            "_id": 0
        }
    }, {
        "$limit": 1
    }
]