public_producer/app/Model/WebsiteCategory.php

<?php

declare(strict_types=1);

namespace App\Model;

use Hyperf\DbConnection\Model\Model;

/**
 */
class WebsiteCategory extends Model
{
    /**
     * The table associated with the model.
     */
    protected ?string $table = 'website_category';

    /**
     * The attributes that are mass assignable.
     */
    protected array $fillable = ['website_id', 'name', 'sort', 'pid', 'seo_title', 'seo_keywords', 'seo_description', 'pid_arr', 'alias', 'aLIas_pinyin', 'category_arr_id', 'category_id', 'is_url', 'web_url'];

    /**
     * The attributes that should be cast to native types.
     */
    protected array $casts = [];
    public function children()
    {
        return $this->hasMany(WebsiteCategory::class, 'pid', 'category_id');
    }
}