搜索课程，使结果按照开课时间、创建时间倒排

app/controllers/courses_controller.rb

@@ -107,7 +107,7 @@ class CoursesController < ApplicationController
       courses = Course.visible
       @courses = paginateHelper courses,10
     else
-      courses = Course.visible.where("LOWER(name) like '%#{params[:name].to_s.downcase}%'")
+      courses = Course.visible.where("LOWER(name) like '%#{params[:name].to_s.downcase}%'").order("time desc, created_at desc")
       @courses = paginateHelper courses,10
     end
    @name = params[:name]