Rails 3 ActiveRecord conditional includes?

I know this can be done:

Article.where("published_at <= ?", Time.now).includes(:comments)

But w开发者_开发知识库hat if I'd like to only get comments posted in the past month?

Does the .includes operator allow conditions?

Article.includes(:comments).where("articles.published_at <= ? and comments.created_at >= ?", Time.now, Time.now - 1.month)

EDIT:

Article.joins(:comments).where("articles.published_at <= ? and comments.created_at >= ?", Time.now, Time.now - 1.month)

In Rails4, it should be: Article.includes(:comments).where("articles.published_at <= ? and comments.created_at >= ?", Time.now, Time.now - 1.month).references(:comments)

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