How to efficiently filter ActiveRecord associations in Rails 7 with multiple conditions?
Can someone help me understand I'm trying to implement I'm confused about I'm not sure how to approach I'm working on a Ruby on Rails 7 application where I need to filter records based on multiple conditions from associated models... I have a `User` model that has many `Posts`, and I want to retrieve users who have created posts in a specific category and also have more than a certain number of comments on those posts. I tried using a combination of `joins` and `where` clauses, but I'm running into performance optimization and unexpected behavior. Here's the code I've written so far: ```ruby class User < ApplicationRecord has_many :posts end class Post < ApplicationRecord belongs_to :user has_many :comments end # Fetching users with specific criteria User.joins(posts: :comments) .where(posts: {category: 'tech'}) .group('users.id') .having('COUNT(comments.id) > ?', 5) ``` The above query is returning results, but it's not performant as the dataset grows. I noticed that it also returns users who have posts in the 'tech' category but only a few comments across all their posts, which isn't the intended behavior. I've also tried to use subqueries to filter the posts first before joining with comments: ```ruby User.where(id: Post.select(:user_id) .where(category: 'tech') .group(:user_id) .having('COUNT(comments.id) > ?', 5) ) ``` This subquery approach seems to be closer to what I need, but I'm still unsure if this is the best practice or if there's a more efficient way to achieve this filtering. Additionally, I get errors like `PG::UndefinedTable: behavior: relation "comments" does not exist` when I try to run migrations or tests related to comments due to some misconfiguration. Can anyone suggest an optimal way to handle this filtering while ensuring both performance and correctness? Any ideas what could be causing this? I'm working on a web app that needs to handle this. Is there a better approach? Has anyone dealt with something similar? I'm developing on Ubuntu 22.04 with Ruby. Any suggestions would be helpful. I'm working on a mobile app that needs to handle this. Any advice would be much appreciated. The project is a microservice built with Ruby. I'd love to hear your thoughts on this.