Laravel数据库迁移给表加注释

public function up()

{
    Schema::create('activitys', function (Blueprint $table) {
        $table->increments('activity_id')->comment('活动表');
        $table->timestamps();
    });
    DB::statement("ALTER TABLE `tbl_activitys` comment'活动表'");//表注释一定加上前缀
}