Laravel 递归

CREATE TABLE `goods_category` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT COMMENT ‘主键id‘,
  `name` varchar(500) DEFAULT ‘‘ COMMENT ‘分类名称‘,
  `pid` int(5) unsigned DEFAULT ‘0‘ COMMENT ‘父级id‘,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=39 DEFAULT CHARSET=utf8mb4 COMMENT=‘商品分类表‘;

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class GoodsCategory extends Model
{
    //
    public $table = ‘goods_category‘;

    public function children()
    {
        return $this->hasMany(get_class($this), ‘pid‘ ,‘id‘);
    }

    public function allChildren()
    {
        return $this->children()->with( ‘allChildren‘ );
    }
}

 function test(){
        $list = GoodsCategory::with(‘allChildren‘)->first();
        return $list;
    }