Use find to initialize a constant?

Question

Something like this:

class Category

   SOME_CATEGORY = find_by_name(\"some category\")

end

Category::SOME_CATEGORY
tried wi

Answer 1

If you don't want to hit the database each time you'll have to cache the model. There are several ways to do this, but one quick way is using Memoization. This was introduced in Rails 2.2.

class Category < ActiveRecord::Base
  class << self
    extend ActiveSupport::Memoizable
    def named(name)
      find_by_name(name)
    end
    memoize :named
  end
end

Use it like this.

Category.named("some category") # hits the database
Category.named("some category") # doesn't hit the database

The cache should stay persistent across requests. You can reset the cache by passing true as the last parameter.

Category.named("some category", true) # force hitting the database