Is there an ActiveRecord equivalent to using a nested subquery i.e. ... where NOT IN(select...) ?
- by Snorkpete
I have 3 models: Category, Account, and SubAccount
The relations are:
Accounts has_many :sub_accounts
Categories has_many :sub_accounts
I wanted to get a list of all Categories that are not used by a given account.
My method in the Category model currently looks like:
class Category < ActiveRecord::Base
def self.not_used_by(account)
Category.find_by_sql("select * from categories where id not in(select category_id from sub_accounts where account_id = #{account.id})")
end
end
My question is, is there a cleaner alternative than using SQL?
NB. I am currently using Rails 3(beta)
