Hey Dan, Got another question about this.
What if salary is not really a column in the database? What if it's a variable which is just a function of two other database columns? For example what if 'salary' is a variable defined in the Magazine object but it's either 'gross_income' or 'gross_pay' (depending on which is selected via a third column's value) ? When I try to use the non-column *variable* salary below, i get the following error: "PGError: ERROR: column "salary" does not exist" Basically I'm just asking how to sum up related objects' variables. (which are not stored in the database) On Sep 22, 1:14 pm, Dan Manges <[EMAIL PROTECTED]> wrote: > On Sep 22, 1:41 pm, dschruth <[EMAIL PROTECTED]> wrote: > > > Lets just use your Magazine / Subscriber example for now. > > > I want to do something like this: > > -------------------------------------------------------- > > class Magazine > > def subscriber_salaries > > Subscriber.calculate(:sum, :salary, :conditions => "magazine_id = > > " + id.to_s) # PGError: ERROR: column "magazine_id" does not > > exist > > end > > end > > You need to implement subscriber_salaries like this: > > class Magazine > has_many :subscriptions > has_many :subscribers, :through => :subscriptions > def subscriber_salaries > subscribers.calculate(:sum, :salary) > end > end > > -Dan --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
