async_multi_del

异步的删除多条数据

    ///
    /// \brief asynchronous multi_del
    ///     delete multiple value by key from the cluster.
    ///     will not be blocked, return immediately.
    /// \param hashkey
    /// used to decide which partition to get this k-v
    /// \param sortkeys
    /// all the k-v under hashkey will be sorted by sortkey. should not be empty.
    /// \param callback
    /// the callback function will be invoked after operation finished or error occurred.
    /// \param timeout_milliseconds
    /// if wait longer than this value, will return time out error
    /// \return
    /// void.
    ///
    virtual void async_multi_del(const std::string &hashkey,
                                 const std::set<std::string> &sortkeys,
                                 async_multi_del_callback_t &&callback = nullptr,
                                 int timeout_milliseconds = 5000) = 0;