Code Explainers

Code explainers tagged #denormalization

ruby 
class Post < ApplicationRecord
  belongs_to :author, counter_cache: false
  has_many :comments, dependent: :destroy
end

A custom counter cache in Rails

counter-cache callbacks associations
Intermediate 7 steps
ruby 
class CreateCommentsWithCounterCache < ActiveRecord::Migration[7.1]
  def change
    create_table :posts do |t|
      t.string :title, null: false

How counter caches work in Rails

counter-cache migrations associations
Intermediate 6 steps