Question

我创建了一个关联，以减少像这样的构造中的查询数量

@user.all do |user|
  puts "User ##{user.id}, post count: #{user.posts_count}"
end

我的模特：

class User
 one_to_many :posts
 one_to_one :posts_count, :read_only => true, :key => :id,
    :dataset => proc{Post.where(:user_id => :id, :deleted => false).select{count(Sequel.lit("*")).as(count)}},
    :eager_loader => (proc do |eo|
      eo[:rows].each{|p| p.associations[:posts_count] = nil}
      Post.where(:user_id => eo[:id_map].keys, :deleted => false).
        select_group(:user_id).
        select_append{count(Sequel.lit("*")).as(count)}.
        all do |t|
          p = eo[:id_map][t.values.delete(:user_id)].first
          p.associations[:posts_count] = t
        end
      end)

  def posts_count
    super.try(:[], :count) || 0
  end

  # ...
end

升级到续集4.1.0后我获得unitialized constant PostsCount，而在续集3.44中，它运行良好。我该如何解决这个问题？

Answer 1

添加类属性可解决此问题。像这样包括:class => "Post"：

one_to_one :posts_count, :read_only => true, :key => :id, :class => "Post",
#...

续集升级后高级计数关联破裂

1 个答案: