Rails 7.1: How to prevent N+1 queries in deeply nested associations with custom scopes?
I'm deploying to production and I'm working with N+1 query issues in my Rails 7.1 application when trying to load a nested association with custom scopes. My models are set up as follows: ```ruby class User < ApplicationRecord has_many :posts end class Post < ApplicationRecord belongs_to :user has_many :comments end class Comment < ApplicationRecord belongs_to :post scope :recent, -> { order(created_at: :desc).limit(5) } end ``` I'm trying to fetch users along with their recent posts and comments in an efficient way. My query looks like this: ```ruby @users = User.includes(posts: :comments).where(posts: { created_at: 1.week.ago..Time.now }) ``` However, even with the `includes`, I'm still hitting the database multiple times when I iterate through the records: ```ruby @users.each do |user| user.posts.each do |post| post.comments.each do |comment| puts comment.content end end end ``` The debug logs show multiple queries for the comments, indicating that the eager loading isn't working as expected. I've tried using `joins` instead of `includes`, but that doesn't suit my needs since I want to filter the posts. I've also read about using `preload`, but I'm not sure how to combine that with the custom scope on comments. Any advice on how to resolve this scenario and effectively eager load comments? Is there a better approach to handle this situation that maintains performance? This issue appeared after updating to Ruby 3.11.