Rails has_many with alias name

Question

Give this a shot:

has_many :jobs, foreign_key: "user_id", class_name: "Task"

Note, that :as is used for polymorphic associations.

You could also use alias_attribute if you still want to be able to refer to them as tasks as well:

class User < ActiveRecord::Base
  alias_attribute :jobs, :tasks

  has_many :tasks
end

If you use has_many through, and want to alias:

has_many :alias_name, through: model_name, source: initial_name

To complete @SamSaffron's answer :

You can use class_name with either foreign_key or inverse_of. I personally prefer the more abstract declarative, but it's really just a matter of taste :

class BlogPost
  has_many :images, class_name: "BlogPostImage", inverse_of: :blog_post  
end

and you need to make sure you have the belongs_to attribute on the child model:

class BlogPostImage
  belongs_to :blog_post
end