How to optimize ActiveRecord queries with joins and select to improve performance in Ruby on Rails?
I'm integrating two systems and I'm currently working on a Ruby on Rails 6 application that has a important performance scenario when querying data from related models. I've noticed that using `includes` for eager loading is causing unnecessary database calls, and it's not as performant as I expected. For example, I have two models: `User` and `Post`, where a user can have many posts. The query I'm using is as follows: ```ruby User.includes(:posts).where(active: true).each do |user| puts user.posts.map(&:title) end ``` However, this results in multiple database queries when I'd like to retrieve only the users with their active posts. When I run this with `bullet` gem, I'm getting warnings that it's generating too many queries. I tried switching to `joins` and `select` to improve this: ```ruby User.joins(:posts).select('users.*, posts.title').where(active: true).each do |user| puts user.title # This throws an behavior because user.title is not defined end ``` The behavior I'm working with is that the `title` method is not accessible on the `user` object because I'm selecting fields from both tables. I understand that using `select` limits the fields returned, but I need both the user data and the post titles. What is the best way to structure this query to optimize performance while ensuring that I can access the relevant fields without running into method errors? Additionally, should I consider alternative approaches like raw SQL or other querying methods for better performance? Any guidance or best practices would be greatly appreciated! This is part of a larger desktop app I'm building. Thanks, I really appreciate it!