/**
  * Run the migrations.
  *
  * @return void
  */
 public function up()
 {
     Schema::table('trackings', function (Blueprint $table) {
         $table->date('tracking_date');
     });
     foreach (Tracking::all() as $tracking) {
         $tracking->tracking_date = $tracking->created_at;
         $tracking->save();
     }
 }