MongoDB Correct Schema for aggregated data

Question

I have a big collection that holds lots of stats, since I want to generate reports, I am running a daily cron which aggregates data from the main collection to a smaller one

Answer 1

This schema simplify a lot range queries and array is a common way of store these data series.

{
    'order_id': 'VjprK',
    'user_id': '777',
    'data': [
        {
            date: MongoDate(2015-04-18),
            value: 100
        },
        {
            date: MongoDate(2015-04-19),
            value: 200
        }
        ...
    ]
}