Rails 7.1: implementing complex query optimizations leading to N+1 problems
I'm having a hard time understanding I'm having a hard time understanding I tried several approaches but none seem to work. I need help solving I've been struggling with this for a few days now and could really use some help. I'm working on a personal project and I’m currently working on a Rails 7.1 application where I'm experiencing important performance optimization with a complex query that seems to be suffering from N+1 query problems. I have a `Post` model that has many `Comments`, and I'm trying to display posts along with their comments on the index page. However, when I access the index page, the performance is noticeably slow. I initially tried using `includes` to eager load the comments, but it doesn’t seem to be working as expected. Here’s the code snippet I have: ```ruby @posts = Post.includes(:comments).all ``` Despite this, I still get multiple SQL queries when loading the comments, as indicated in the logs: ``` Post Load (0.5ms) SELECT "posts".* FROM "posts" Comment Load (1.0ms) SELECT "comments".* FROM "comments" WHERE "comments"."post_id" = ? /* N times */ ``` I've confirmed that I have the correct associations set up in my models: ```ruby class Post < ApplicationRecord has_many :comments end class Comment < ApplicationRecord belongs_to :post end ``` I also tried using `joins` in place of `includes`, but that didn’t seem to work either, and it resulted in an behavior when trying to access associated comments in the view. What’s perplexing me is why eager loading doesn’t seem to be preventing the N+1 queries. I’ve also checked my database structure and everything seems to be in order. Is there something I'm missing in how I'm using `includes` that could be causing this performance scenario? Any insights or solutions would be greatly appreciated! Has anyone else encountered this? What's the best practice here? I recently upgraded to Ruby 3.9. I'd love to hear your thoughts on this. I'm coming from a different tech stack and learning Ruby. Any ideas how to fix this?