Group by time periods.

[Quoted] I have a database with 5 minute samples of various quantities.

e.g. consider a simplified table with
id, value, timestamp

where 'id' is integer, 'value' is a float and 'timestamp' is datetime.

I would like to select in groups averaged by hour so that e,g., the output could be the average of 12 consecutive timestamps, plus a timestamp of the starting hour.

wring procedural code to do it is not hard but I wondered if in fact there was a way to do it in Mysql.

I thought of of 'group by hour', but that would be just 24 samples!

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