thinkphp 访问不同前缀表

$Model=new Model();
        $goods=$Model->Table('sdb_goods');

       $param['brief']=array('like','%'.$p_title.'%');
       $param['name']=array('like','%'.$p_title.'%');
       $param['_logic']='or';
       $goods_list=$goods->field('name,price,goods_id,mktprice,small_pic')->where($param)->select();

       $this->assign('seek_drug',$goods_list);