classPhoto
      
       'complete')  scope :batch, unscoped.where(:status=>'batch')  scope :queue, unscoped.where(:status=>'queue')   scope :ongoing, -> { where(end_at: nil) }   scope :where_ceid_and_key, ->(ceid, key){where(["`ceid` = ? AND `key` = ?", ceid, key])} ...end
      

定义 或 去掉默认排序

class  < ::  def self.default_scope    where :published => true  endend.          # Fires "SELECT * FROM posts WHERE published = true".. # Fires "SELECT * FROM posts"