Calling find on AR class, order by association count?


#1

I suspect that this is going to wind up trivial and I’m going to slap
myself in the head…

Suppose I have User and Comment AR classes.

User has_many :comments, Comment belongs_to :user

I want to do a User.find, which returns User objects in order of which
user has the most comments. I suspect that this involves renaming the
COUNT(*) results of a sub-select so that I can order by them.

Answers, links to answers?

-Matt


#2

hi Matt,

have a look at ActiveRecord#calculations in the api
basically something like this:

topspammers = Comment.count(:all, :group => ‘user_id’ , :order =>
‘count_all desc’)

gives you a nice OrderedHash with the user_id as key and the number
of comments belonging to that user as the value

hth

On 6/6/06, removed_email_address@domain.invalid
removed_email_address@domain.invalid wrote:

Answers, links to answers?

-Matt


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