Rails eager loading

Posted by Dimitar Vouldjeff on Stack Overflow See other posts from Stack Overflow or by Dimitar Vouldjeff
Published on 2010-05-24T10:25:39Z Indexed on 2010/05/24 10:31 UTC
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ruby-on-rails

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eager-loading

HI, I have a Test model, which has_many questions, and Question, which has_many answers... When I make a query for a Test with :include => [:questions, {:questions => :answers}] ActiveRecord makes two more queries to fetch the questions and then to fetch the answers - it doesn`t join them!!! When I do the query with :joins ActiveRecord makes the query, but later when I need the Test.questions or Test.questions.answers ActiveRecord makes again those 2 extra queries!!! And later when I enumerate the questions or answers in the log I see other queries for each object, but it has Cache tag...

Is this normal?

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