Ruby on Rails activerecord find average in one sql and Will_Paginate

Posted by Darkerstar on Stack Overflow See other posts from Stack Overflow or by Darkerstar
Published on 2010-03-28T07:10:37Z Indexed on 2010/03/28 7:13 UTC
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rails

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will-paginate

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ruby

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model

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has-many

Hi all

I have the following model association: a student model and has_many scores.

I need to make a list showing their names and average, min, max scores. So far I am using student.scores.average(:score) on each student, and I realise that it is doing one sql per student. How can I make the list with one joined sql?

Also how would I use that with Will_Paginate plugin?

Thank you

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