Say I have:
class Relationship < ActiveRecord::Base
belongs_to :parent, :polymorphic => true
and then several models like:
class Person < ActiveRecord::Base
has_many :parents, :as => :parent, :class_name => “Relationship”
I do not want to allow a person to be deleted if they are still being
used by a relationship. I think I could come up with a way to do this
with Relationship.find(:first. Probably return just the id. If I get
anything back, the validate method could fail. Something like that.
But I’m wondering if using “rules” inside of PostgreSQL would be
significantly faster? I have never done rules so I’m a little timid.