i'm developing a system that will collect user activities samples (opened a window, scrolls, enter page, leave page, etc.) and i'm looking for the best way to store these samples and query it.
i prefer something smart where i can execute sql-like group by queries (for example give me all the window open events grouped by date and hour), and of course something flexible enough in case i'll need to add columns in the future.
i'm trying to avoid thinking about all the queries i might need and just save an aggregated version of the data by time, since i'd like to do drill-downs. (for example, count all the window open events by date and time, and then see all event in each time-frame, or change it to be by unique userId).
thanks.
PS - i currently use MySql for this task, but the data is expected to grow rapidly. I've experimented with mongoDB as well.