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In-Reply-To: <314a41cc2ff94e83605c9378b44e8...@ruby-forum.com>
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From: Colin Law <clan...@googlemail.com>
Date: Mon, 30 Apr 2012 09:14:15 +0100
Message-ID: <CAL=0gLvGVFoTpJoWDFDFhPONbGe4g9Tpf7qUYZuAAViQoFk...@mail.gmail.com>
Subject: Re: [Rails] find_all_by.association
To: rubyonrails-talk@googlegroups.com
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On 30 April 2012 09:03, Soichi Ishida <li...@ruby-forum.com> wrote:
> Rails 3.1.3
>
> I have tables
>
> User =C2=A0=3D> has_many :contribution

That should be :contributions, plural.

> Contribution =3D> belongs_to :user
>
> in user.rb, I would like to define a method to compute the total
> contribution
> (sum of field 'price:integer' )
>
> =C2=A0def total_contribution
> =C2=A0 =C2=A0@contributions =3D Contribution.find_all_by_user(self)

Just use
@contributions =3D self.contributions

Colin