MongoDB size limit problem.

[wythe51]

假如要儲存「每小時的資料」與「每五分鐘的資料」，
可能會超過 mongoDB 的限制 (16MB)。

目前只能先儲存「每天的資料」，
有待找尋解法。

If we want to store "every-hour" or "every-five-minute" data,
it may cause the document exceed size limit of mongoDB, which is only 16MB.

So far we can only store "every-day" data,
and we're still searching for any solution. 😓