Thanks for the response, However, I tired what you suggested but only got to the same point as before.
Both of these ways: table1.calculate(:sum, :enrich_bead_count_hemo, OR table1.sum(:enrich_bead_count_hemo give me the same answer: at total of *all* the rows in the other table. But I want a sum of *just* the *associated* rows. I was able to do this when the tables where directly related (with a :condition statement). But I don't quite know how to do that yet for HABTM or "has many :foo => :through" Dave On Sep 20, 9:53 pm, Dan Manges <[EMAIL PROTECTED]> wrote: > You should take advantage of the association proxies. Something like > this should work. > > class Magazine > has_many :subscriptions > has_many :subscribers, :through => :subscriptions > end > > class Subscription > belongs_to :magazine > belongs_to :subscriber > end > > class Subscriber > has_many :subscriptions > end > > Now you can do calculations like this: > > class Magazine > def youngest_subscriber_birthday > subscribers.calculate(:max, :date_of_birth) > end > end > > You should be able to do the calculation the same way for your > 'enrich_bead_count_hemo'. > > -Dan Mangeshttp://www.dcmanges.com/blog > > On Sep 20, 10:06 pm, dschruth <[EMAIL PROTECTED]> wrote: > > > Hi, > > > I'm trying to sum up the records in a related table that used to just > > be a child table. This line used to work: > > > table1.sum(:enrich_bead_count_hemo, :conditions => "table2_id = " + > > id.to_s) > > > now I've got an intermediate "has and belongs to many" = HABTM table > > inbetween them. Could somebody help me figure out how to sum across > > two tables? I'm thinking i might have to use the custom SQL "join" > > attribute of the sum method. > > > Thanks, > > > Dave --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
