Rails eager loading

Question

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?

Just `:include => { :questions => :answers }` will do, no need to specify `:questions` twice. — Stéphan Kochen, May 24 '10 at 10:31
Similar question http://stackoverflow.com/questions/1208636/rails-include-vs-joins — Tatjana N., May 24 '10 at 10:32

score 0 · Accepted Answer · answered May 24 '10 at 22:21

0

I agree with shteef, what happens when you do the following:

:include => { :questions => :answers }

answered May 24 '10 at 22:21

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Rails eager loading

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