Hello,

Data aggregation will be pretty much mandatory when amount of devices increases.
But using views to get data for any time period from main data table ( which contains raw data ) is extremely CPU and I/O intensive. So for example requesting 12 months of data for specific device still requires mysql to go through all 525600 ( 60x24x365 ) records for said device and calculating averages for each month. Which is still 43800 times more work ( excluding time which takes to grab averages ) than just selecting aggregated rows from table containing monthly averages/minimums/maximums. This data would get there at the end of every month via cron script.