很多情况下会用到复合查询：

---

    $query->orWhere('target_type','offline'); 
        $query->where(function($query){
                $query->where('use',1)->orWhere(function($query){
                    $query->where('use',0)
                        ->where('expire_time','>',time())->orWhere('expire_time',0);
                });
            });