ruby on rails - Get all related records using associations -

i'm unable understand how related records using associations instead of associated ids user_id , comment_id. lets suppose have 3 models user, post, comment, image , associations

user   has_many :posts   has_many :comments  post   belongs_to :user   has_many :comments   has_many :images  comment   belongs_to :user   belongs_to :post  image   belongs_to :post 

now have user_id of user , finding user as:

@user = user.find_by_id(params[:id]) @comments = @user.comments 

now fetch these comments each of them related record of post. want post hash instead of post_id corresponding every comment. want in single query. if have idea, please suggest me.

use includes(:association):

@user = user.find_by_id(params[:id]) @comments = @user.comments.includes(:post) 

note: make (second) query.

alternatively, include in initial query:

@user = user.where(id: params[:id]).includes(comments: :post)