在子文檔中查找MongoDb

Question

我需要先通過_id找到該文檔。 然後將文檔找到子文檔其中有一個時間字段中比參數lastTime

var filter = builder.Eq("_id", symbol) & builder.Gt("Update.Time", lastTime); 
var result = await MongoDb.CollectionName.Find(filter).ToListAsync(); 

這個例子具有0

結果如何寫這個查詢更大？我需要得到這個子文檔「更新」或最後3分子文檔

該文件具有以下結構

{ 
    {"_id", symbol}, 
    {"Update", [ 
       {"_id", number}, {"Time", sometime}, {"Version", versionNumber}, 
       {"_id", number}, {"Time", sometime}, {"Version", versionNumber}, 
       {"_id", number}, {"Time", sometime}, {"Version", versionNumber}, 
       {"_id", number}, {"Time", sometime}, {"Version", versionNumber},} 
      ] 
} 

Answer 1

如果MongoDB的控制檯將工作的例子：

> db.doc.save({ 
    "_id":"123", 
    "update":[ 
     {"_id":'1', "time":'345', "Version":'3'}, 
     {"_id":'2', "time":'234', "Version":'4'} 
    ] 
}) 
> db.doc.findOne({ _id:"123", "update.time":{ $gt: 344 } }) 

那麼對於C＃請問你可以試試嗎？

var collection = _database.GetCollection<BsonDocument>("name"); 
var filter = Builders<BsonDocument>.Filter.Gt("update.time", 344); 
var result = await collection.Find(filter).ToListAsync(); 

這example

UPD這可以是：

var collection = _database.GetCollection<BsonDocument>("name"); 
var builder = Builders<BsonDocument>.Filter; 
var filter = builder.Eq("_id", id) & builder.Gt("update.time", 344); 
var result = await collection.Find(filter).ToListAsync();