eager load polymorphic rails

To eager load polymorphic associations in Ruby on Rails, you can follow these steps:

1. Define the polymorphic association in the relevant model using the belongs_to and has_many or has_one methods. For example, let's say you have a Comment model that can belong to either a Post or a Video. In the Comment model, you would define the association like this:

class Comment < ApplicationRecord
  belongs_to :commentable, polymorphic: true
end

1. Ensure that the associated models (Post and Video in this case) also have the reverse association defined. For example, in the Post model:

class Post < ApplicationRecord
  has_many :comments, as: :commentable
end

And in the Video model:

class Video < ApplicationRecord
  has_many :comments, as: :commentable
end

1. To eager load the polymorphic association, you can use the includes method when querying the Comment model. This ensures that the associated records are loaded in a single database query, reducing the number of queries executed. For example, to eager load the comments for a specific Post:

@post = Post.includes(:comments).find(params[:id])

1. To access the eager loaded comments, you can simply use the association method as you would with a regular association. For example, to access the comments for the Post:

@post.comments.each do |comment|
  # Do something with each comment
end

That's it! By following these steps, you can eager load polymorphic associations in Ruby on Rails.