phpstock/app/admin/model/GoodBasic.php

<?php
declare (strict_types = 1);

namespace app\admin\model;

use think\Model;

/**
 * @mixin \think\Model
 */
class GoodBasic extends Model
{
    public function brand(){
        return $this->belongsTo(Brand::class,"brand_id","id")->bind(["brand_name"]);
    }

    public function category(){
        return $this->belongsTo(Cat::class,"cat_id","id")->bind(["cat_name","cat_search"=>"search"]);
    }

    public function Unit(){
        return $this->belongsTo(Unit::class,"good_unit","id")->bind(["unit_name"=>"unit"]);
    }
}