You should use text with Rails if you want a string with no length limit. A migration like this: def up change_column :your_table, :your_column, :text end def down # This might cause trouble if you have strings longer # than 255 characters. change_column :your_table, :your_column, :string end should sort things out. You might want :null … Read more
pluck is on the db level. It will only query the particular field. See this. When you do: User.first.gifts.collect(&:id) You have objects with all fields loaded and you simply get the id thanks to the method based on Enumerable. So: if you only need the id with Rails 4, use ids: User.first.gifts.ids if you only … Read more
Here’s a complete answer to this issue, in case people visiting this question are new to Ruby on Rails and having a hard time putting everything together (as I was when I first looked into this). Some parts of the solution take place in your Migrations and some in your Models: Migrations class CreatePrivateMessages < … Read more
Group by offer.id, not by sports.name (or sports.id): SELECT o.* FROM sports s JOIN offers_sports os ON os.sport_id = s.id JOIN offers o ON os.offer_id = o.id WHERE s.name IN (‘Bodyboarding’, ‘Surfing’) GROUP BY o.id — !! HAVING count(*) = 2; Assuming the typical implementation: offer.id and sports.id are defined as primary key. sports.name is … Read more
You can scope a validates_uniqueness_of call as follows. validates_uniqueness_of :user_id, :scope => :friend_id
I suspect that ActiveRecord isn’t noticing that your friends array has changed because, well, the underlying array reference doesn’t change when you: self.friends.push(target) That will alter the contents of the array but the array itself will still be the same array. I know that this problem crops up with the postgres_ext gem in Rails3 and … Read more
This part of your question: I know we can create it manually in PostgreSQL, but the “magic” with Active Record is that the database can be recreated with all the models. tells me that you’re really looking for a way to integrate PostgreSQL functions with the normal Rails migration process and Rake tasks such as … Read more
Use CREATE SEQUENCE: CREATE SEQUENCE scores_job_id_seq; — = default name for plain a serial Then add a column default to scores.job_id: ALTER TABLE scores ALTER COLUMN job_id SET DEFAULT nextval(‘scores_job_id_seq’); If you want to bind the sequence to the column (so it is deleted when the column is deleted), also run: ALTER SEQUENCE scores_job_id_seq OWNED … Read more
Have you tried calling the count method on one of the returned Tag objects? Just because inspect doesn’t mention the count doesn’t mean that it isn’t there. The inspect output: [#<Tag id: 401, name: “different”>, … , #<Tag id: 4, name: “family”>] will only include things that the Tag class knows about and Tag will … Read more
I believe what you are looking for is assign_attributes. It’s basically the same as update_attributes but it doesn’t save the record: class User < ActiveRecord::Base attr_accessible :name attr_accessible :name, :is_admin, :as => :admin end user = User.new user.assign_attributes({ :name => ‘Josh’, :is_admin => true }) # Raises an ActiveModel::MassAssignmentSecurity::Error user.assign_attributes({ :name => ‘Bob’}) user.name # … Read more