ruby-on-rails - 从父属性构建查询

Question

从我尝试“缺少 FROM 子句条目”的查询中获取以下错误

基本上，我的问题有很多答案，我试图获得属于“x”类别问题的所有答案

Answer.joins(:question).
from('answers').
where(:question => {:category => @category}).
sort_by(&:created_at).
reverse.
paginate(:page => params[:page], :per_page => 20)

Answer 1

尝试：

Answer.joins(:question => :category).where...

怎么样：

Answer.joins(question: category).where("categories.name = ?", @category).order("answers.created at ASC").paginate(page: params[:page], per_page: 20)