django aggregation to lower resolution using grouping by a date range

Question

horrible title, but let me explain: i\'ve got this django model containing a timestamp (date) and the attribute to log - f.e. the number of users consuming some ressource -

Answer 1

After long trying i made it as SQL-statement:

SELECT FROM_UNIXTIME(AVG(UNIX_TIMESTAMP(date))), SUM(value)
FROM `my_table`
WHERE date BETWEEN SUBTIME(NOW( ), '0:30:00') AND NOW()
GROUP BY UNIX_TIMESTAMP(date) DIV 300
ORDER BY date DESC

with

start_time = SUBTIME(NOW( ), '0:30:00')
end_time = NOW()
period = 300 # in seconds

in the end - not really hard - and indeed independent from the time resolution of the samplings in the origin table.