You cannot use Array#join on an array of strings where some strings are html_safe and others are not...
When you eagerly load an association list using the .include option, and at the same time have a .where on...
When using virtual attributes, the attached trait can be useful to automatically copy errors from one attribute to another.
In modern Rails versions you can also use ActiveRecord's pluck method. >> User.active.pluck(:id) => [1, 5, 23, 42]
There are two distinct ways of commenting Haml markup: HTML and Ruby. HTML comments This will create an HTML comment...
Rails 3, 4, 5, 6 config/application.rb config/environment.rb before the initialize! call (we don't usually edit this file)
Sometimes you want to fetch associations for an ActiveRecord that you already loaded, e.g. when it has deeply nested associations...
When you need to add a event listener to hundreds of elements, this might slow down the browser. An alternative...