修改删除的关联的500问题

app/models/news.rb

@@ -23,7 +23,7 @@ class News < ActiveRecord::Base
   #added by nwb
   belongs_to :course
   belongs_to :author, :class_name => 'User', :foreign_key => 'author_id'
-  has_many :comments, :as => :commented, :dependent => :delete_all, :order => "created_on"
+  has_many :comments, :as => :commented, :dependent => :destroy, :order => "created_on"
   # fq
   has_many :acts, :class_name => 'Activity', :as => :act, :dependent => :destroy
   # 被ForgeActivity虚拟关联