In ruby on rails, is it possible to do a sum query with group by using the find_each batching?

Posted by BarryOg on Stack Overflow See other posts from Stack Overflow or by BarryOg
Published on 2010-05-19T12:18:41Z Indexed on 2010/05/19 12:20 UTC
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Filed under:

ruby

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rails

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activerecord

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group-by

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sum

I'm loading data from my database and I'm doing a sum calculation with a group by.

ElectricityReading.sum(:electricity_value, :group => "electricity_timestamp", :having => ["electricity_timestamp = '2010-02-14 23:30:00'"])

My data sets are extremely large, 100k upwards so I was wondering if its possible to use the find_each to batch this to help with memory overhead.

I can write the batching manually use limit and offset I guess but I'd like to avoid that if the code already exists.

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