When you run rake db:rollback and nothing happens, you are probably missing the latest migration file (or have not...
Adds missing native PostgreSQL data types to ActiveRecord and convenient querying extensions for ActiveRecord and Arel for Rails 4.x...
ActiveRecord offers an explain method similar to using EXPLAIN SQL statements on the database. However, this approach will explain all...
When dealing with time zones in Rails, there is one key fact to keep in mind: Rails has configurable time...
Stackprof is a sampling call-stack profile for Ruby 2.1+. Instead of tracking all method calls, it will simply collect...
Our preferred way of testing ActiveRecord is to simply create/update/destroy the record and then check if the expected behavior has...
Validations should be covered by a model's spec. This card shows how to test an individual validation. This is...
Geordi is now (partially) tested with Cucumber. Yay! geordi cucumber supports a new @solo tag. Scenarios tagged with @solo...
Using Scenic, you can bring the power of SQL views to your Rails application without having to switch your schema...
When dealing with AR scopes, you can remove conditions, order, etc by using the unscope method. It is available on...
Rails 4 introduced raising an error on pending migrations. This is most annoying when you are crafting a migration but...
Rails 5 will introduce ActiveRecord::Relation#or. On Rails 4 and 3.2 you can use the activerecord_any_of gem...
It smells. Rethink your code design. Code example with makandra/has_defaults: class Post < ActiveRecord::Base has_defaults tags: [] # field in db...
As you most likely know validates_uniqness_of :foreign_id does not allow nil values by default.
Use form models to handle this problem Or soften the validation to validates_presence_of :parent
Use base_class. This traverses up the hierarchy until it encounters either a class inheriting from ActiveRecord::Base or
In tests, it is sometimes useful to create records with specific ids. On PostgreSQL this can cause problems: Usually, PostgreSQL...
The migration DSL now supports adding and removing foreign keys. They are dumped to schema.rb as well. At this time...
When working with ActiveType you will often find it useful to cast an ActiveRecord instance to its extended ActiveType::Record...
Note: ActiveRecord::Base#becomes has a lot of quirks and inconsistent behavior. You probably want to use ActiveType.cast instead.
Capistrano 3 is a major rework of the framework and requires several adjustments to your deploy configuration files. The biggest...
Re-creating a complex ActiveRecord scenario quickly without setting up a full-blown Rails app can come in handy e.g...
Several Rails migration methods accept index: true as an option to create an index. In some cases (like #add_column...
You can freeze any Ruby object to prevent further modification. If you freeze an ActiveRecord and try to set an...