Estoy tratando de transponer una consulta de MongoDb a una consulta de C# Mongo Driver. El propósito es hacer una unión entre colecciones . Menciono que en este caso, anidar documentos no es una opción.

Entonces, la siguiente consulta de MongoDb funciona como se esperaba:

 db.Orders.aggregate( [ {$lookup: { from: 'Status', localField: 'orderStatusId', foreignField: '_id', as: 'status' }}, {$lookup: { from: 'PaymentTypes', localField: 'paymentTypeId', foreignField: '_id', as: 'paymentType' }}, {$unwind: { path: "$status" }}, {$unwind: { path: "$paymentType", }}] )

Sin embargo, en C# nunca encuentra ningún documento:

 var orders = await _ordersCollection.Aggregate() .Lookup(_statusCollection, order => order.StatusId, status => status.Id, (Order order) => order.Status) .Lookup(_paymentTypeCollection, order => order.PaymentTypeId, paymentType => paymentType.Id, (Order order) => order.PaymentType) .Unwind(order => order.Status) .Unwind(order => order["paymentType"]) .ToListAsync();

Tengo los siguientes objetos:

 public class Order { [BsonId(IdGenerator = typeof(GuidGenerator))] public Guid Id { get; set; } [BsonElement("status")] [BsonIgnoreIfNull] public Status Status { get; set; } [BsonElement("paymentType")] [BsonIgnoreIfNull] public PaymentType PaymentType { get; set; } [BsonElement("paymentTypeId")] public Guid PaymentTypeId { get; set; } [BsonElement("orderStatusId")] public Guid StatusId { get; set; } } public class PaymentType { [BsonId(IdGenerator = typeof(GuidGenerator))] public Guid Id { get; set; } [BsonElement("name")] public string Name { get; set; } } public class Status { [BsonId(IdGenerator = typeof(GuidGenerator))] public Guid Id { get; set; } [BsonElement("name")] public string Name { get; set; } }