socialforge/db/migrate/20140605025300_create_course_infos.rb

class CreateCourseInfos < ActiveRecord::Migration
  def change
    create_table :course_infos do |t|
      t.integer :course_id
      t.integer :user_id
      t.timestamps
    end

    #迁移课程管理员数据
    Project.all.each do |project|
      if project.project_type == 1
        course = Course.find_by_extra(project.identifier)
        if course
          projectinfos = ProjectInfo.find_all_by_project_id(project.id)
          projectinfos.each do |projinfo|
            courseinfo = CourseInfos.new
            courseinfo.course_id = course.id
            courseinfo.user_id = projinfo.user_id
            courseinfo.save(:validate => false)
          end
        end
      end
    end
  end
end