mysql 預查詢-無限極分類

class Test extends Controller{
    public function index(){
        $id = input('id');
        //$this->setparent();
       $this->setchild($id);
    }

    public function setparent(){
        $list = [];
        $list = db('ce')->insert([
            'cname'=>rand(1000,9999),
            'f_id'=>0,
            'left_num'=>1,
            'right_num'=>2,
            'level' =>1
        ]);
    }
    public function setchild($fid){
        $p_data = db('ce')->where('id',$fid)->find();
        $max_data = db('ce')->where('f_id',$fid)->max('right_num');
        if(empty($max_data)){
            db('ce')->where('right_num','>=',$p_data['right_num'])->setInc('right_num',2);
        }else{
            db('ce')->where('left_num','>=',$p_data['left_num'])->setInc('left_num',2);
            db('ce')->where('right_num','>=',$p_data['right_num'])->setInc('right_num',2);
        }
        $list = [];
        $list = db('ce')->insert([
            'cname'=>rand(1000,9999),
            'f_id'=>$p_data['id'],
            'left_num'=>$p_data['left_num']+1,
            'right_num'=>$p_data['right_num']+1,
            'level' =>1
        ]);
    }
    
    public function query($id){
        $p_data = db('ce')->where('id',$id)->find();
       $data = db('ce')->where('pt_left','>',$p_data['left_num'])->where('pt_right','<',$p_data['right_num'])->select();
        
    }
}