Mongodb Mongoose以最小相对时间差获取最后的X值

我试图得到DB条目的确切数量，它们彼此之间的时差最小。例如，传感器大约每1000毫秒向数据库写入一次数据，但我想读取20个值，最小时间差为1小时

目前，我使用$gt阅读，但这会从数据库中提取72000（20x60mx60s）个条目

然后我对其进行过滤：

  filterSensorHistory: (data, callback)->
    self = @
    data = _.sortBy(data, 'timestamp').reverse()
    lastEntry = moment(data[0].timestamp).add(5, self.timeUnit) #add 5 units to the last entry (for processing delay), works seconds & minutes
    data = data.filter (dataItem, index)->
      return false if lastEntry.diff(moment(dataItem.timestamp), self.timeUnit) <= 1 #if less than 1 time unit diff. reject
      lastEntry = moment(dataItem.timestamp)
      return true
    data = data.splice(0,HISTORY_LENGTH)
    data = data.map (dataItem)->
      return { x: moment(dataItem.timestamp).toDate(), y: dataItem.value }
    data.reverse()
    return callback null, data

---

既然您已经意识到，一旦检索到文档，就在代码中这样做是一个坏主意，那么让我们更清楚地了解数据本身的样本是什么样的呢？如果您只是显示了几个文档作为输入，以及您希望从该输入中获得的结果，那么您可能会从其他人那里得到一些反馈，他们可能会以不同的方式看待问题。然后可能会给你一个解决方案。问这个问题的目的是什么，不是吗？让人们更容易提供帮助。你能做的最好的事情就是“更新你的MongoDB”。2.4甚至不再得到官方支持，而且它还存在已知的bug（以及有问题的bug），并且在过去几年中遗漏了所有主要功能的更改。@NeilLunn提供了一些示例数据。基本上，唯一重要的道具是时间戳。我试图更新它，但它运行在raspberry pi 3上，

sudo apt get install mongodb server

告诉我已经有了最新版本。我认为这是因为对32位体系结构的支持在以后的版本中已经被弃用了：嗯？不要相信你读到的一切。32位目标的官方版本每天都在制作，任何说它不受支持的说法都是完全错误的。至于“有人从源代码为您构建”，那么我只需几秒钟就可以找到raspberry pi的至少v3二进制文件，毫无疑问，也有人拥有最新的构建。事实上，这与信任一个三年前有四张选票的帖子相比，3.x似乎可以安装，但它看起来有点粗糙：，到目前为止，2.4.10没有遇到任何问题/限制。

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