screen/application/common/model/Tag.php

<?php

namespace app\common\model;

use think\Db;
use think\db\Query;
use think\Model;

/**
 * @method static Query|static hot($hot=1)
 */
class Tag extends Model
{
    // 自动写入时间戳字段
    protected $autoWriteTimestamp = false;

    public function video(){
        return $this->belongsToMany(Video::class,'video_tag');
    }
    protected static function init()
    {
        self::afterDelete(function (self $tag){
            VideoTag::tag($tag['id'])->delete();
        });
    }
    public function scopeHot(Query $query,$hot=1){
        $query->where('is_hot',$hot);
    }
}