I’m trying to install Rails 3 on a brand new MacBook Pro running OS X 10.6.3, Ruby 1.8.7, and Rails 2.3.5 and I’m wondering if I’ve hosed myself. So far, I’ve run these commands: $ gem update –system $ gem install arel tzinfo builder memcache-client rack rack-test rack-mount erubis mail text-format thor bundler i18n $ … Read more
Could you explain in detail what the :before_save and :before_create Ruby on Rails callbacks are, and what they have to do with Rails validations? Does validation occur after :before_save or :before_create? 3 Answers 3
I recently upgraded to OSX 10.7, at which point my rails installation completely borked when trying to connect to the psql server. When I do it from the command line using psql -U postgres it works totally fine, but when I try to run the rails server or console with the same username and password, … Read more
How do you do an OR query in Rails 3 ActiveRecord. All the examples I find just have AND queries. Edit: OR method is available since Rails 5. See ActiveRecord::QueryMethods 14 Answers 14
I am using Ruby on Rails 3.2.2 and I would like to know if the following is a “proper”https://stackoverflow.com/”correct”https://stackoverflow.com/”sure” way to override a setter method for a my class attribute. attr_accessible :attribute_name def attribute_name=(value) … # Some custom operation. self[:attribute_name] = value end The above code seems to work as expected. However, I would like … Read more
I can run all tests in a single file with: rake test TEST=path/to/test_file.rb However, if I want to run just one test in that file, how would I do it? I’m looking for similar functionality to: rspec path/to/test_file.rb -l 25 15 Answers 15
Is there a rails-way way to validate that an actual record is unique and not just a column? For example, a friendship model / table should not be able to have multiple identical records like: user_id: 10 | friend_id: 20 user_id: 10 | friend_id: 20 3 Answers 3
I have a large hash with nested arrays and hashes. I would like to simply print it out so it ‘readable’ to the user. I would like it to be sort of like to_yaml – that’s pretty readable – but still too tech looking. Ultimately its going to be end users who need to read … Read more
Please help me in understanding the :source option of has_one/has_many :through association. The Rails API explanation makes very little sense to me. “Specifies the source association name used by has_many :through => :queries. Only use it if the name cannot be inferred from the association. has_many :subscribers, :through => :subscriptions will look for either :subscribers … Read more
In Rails, you can find the number of records using both Model.size and Model.count. If you’re dealing with more complex queries is there any advantage to using one method over the other? How are they different? For instance, I have users with photos. If I want to show a table of users and how many … Read more
