ruby-on-rails3, and select distinct using activereccord3

Question

Some methods have been deprecated with Rails3. It is the case in particular with the following call !

Error.find(:all, :select => 'DISTINCT type')

Is anybody have an idea, how to convert this call to an ActiveRecord3 valid statement ?

I found nothing on the web ...

Thanks

Answer 1

Just use the new select query method.

Error.select('DISTINCT type')

Answer 2

If you seek to get a distinct set of returns against a PostGreSQL database, you must use:

Error.select('DISTINCT ON(type)')

and if your in the context of a scope, perhaps something like the following to ensure that you get all the fields:

scope :running, select('DISTINCT ON(campaigns.budget) campaigns.*')