How do I aggregate activerecord model data for a specific time period?

Posted by gsiener on Stack Overflow See other posts from Stack Overflow or by gsiener
Published on 2010-05-14T02:13:41Z Indexed on 2010/05/14 3:54 UTC
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ruby-on-rails

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activerecord

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aggregate

I'm collecting data from a system every ~10s (this time difference varies due to communication time with networked devices). I'd like to calculate averages and sums of the stored values for this activerecord model on a daily basis. All records are stored in UTC.

What's the correct way to sum and average values for, e.g., the previous day from midnight to midnight EST? I can do this in sql but don't know the "rails way" to make this calculation.

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