Model.select(:rating) The result of this is a collection of Model objects. Not plain ratings. And from uniq‘s point of view, they are completely different. You can use this: Model.select(:rating).map(&:rating).uniq or this (most efficient): Model.uniq.pluck(:rating) Rails 5+ Model.distinct.pluck(:rating) Update Apparently, as of rails 5.0.0.1, it works only on “top level” queries, like above. Doesn’t work on … Read more
Rails’ ActiveSupport adds underscore to the String using the following: class String def underscore self.gsub(/::/, “https://stackoverflow.com/”). gsub(/([A-Z]+)([A-Z][a-z])/,’\1_\2′). gsub(/([a-z\d])([A-Z])/,’\1_\2′). tr(“-“, “_”). downcase end end Then you can do fun stuff: “CamelCase”.underscore => “camel_case”
Now, the accepted way to set the humanized names and custom error messages is to use locales. # config/locales/en.yml en: activerecord: attributes: user: email: “E-mail address” errors: models: user: attributes: email: blank: “is required” Now the humanized name and the presence validation message for the “email” attribute have been changed. Validation messages can be set … Read more
default_scope This works for Rails 4+: class Book < ActiveRecord::Base default_scope { order(created_at: :desc) } end For Rails 2.3, 3, you need this instead: default_scope order(‘created_at DESC’) For Rails 2.x: default_scope :order => ‘created_at DESC’ Where created_at is the field you want the default sorting to be done on. Note: ASC is the code to … Read more
The other answerers are all correct, but a friend asked me to explain this to him and what it really boils down to is how Ruby handles variables, so I thought I would share some simple pictures / explanations I wrote for him (apologies for the length and probably some oversimplification): Q1: What happens when … Read more
As of Rails 2.3.9, there is a setting in config/application.rb in which you can specify directories that contain files you want autoloaded. From application.rb: # Custom directories with classes and modules you want to be autoloadable. # config.autoload_paths += %W(#{config.root}/extras)
There is a now a “correct” mechanism in Rails 4: >> Model.none => #<ActiveRecord::Relation []>
For RVM & OSX users Make sure you use latest rvm: rvm get stable Then you can do two things: Update certificates: rvm osx-ssl-certs update all Update rubygems: rvm rubygems latest For non RVM users Find path for certificate: cert_file=$(ruby -ropenssl -e ‘puts OpenSSL::X509::DEFAULT_CERT_FILE’) Generate certificate: security find-certificate -a -p /Library/Keychains/System.keychain > “$cert_file” security find-certificate … Read more
Maybe this is what you’re looking for? string = “line #1″\ “line #2″\ “line #3” p string # => “line #1line #2line #3”
Rack as Design Rack middleware is more than “a way to filter a request and response” – it’s an implementation of the pipeline design pattern for web servers using Rack. It very cleanly separates out the different stages of processing a request – separation of concerns being a key goal of all well designed software … Read more