+ def select_for_klass sel, model_class
+ return nil if sel.nil?
+ # Filter the select fields to only the ones that apply to the
+ # given class.
+ sel.map do |column|
+ sp = column.split(".")
+ if sp.length == 2 && sp[0] == model_class.table_name
+ sp[1]
+ elsif model_class.selectable_attributes.include? column
+ column
+ else
+ nil
+ end
+ end.compact
+ end
+