php接口数据，获取评论列表，按照创建时间，最新的评论在上面

public function get_comments()
    {
        $input = $this->getinput->json(); //先接收

        if (isset($input['page'])) {
            $offset = ($input['page'] - 1) * 10;
            $limit = 10;
        } else {
            $offset = 0;
            $limit = 100;
        }
        $query = $this->db->join('user', 'user.id = comment.user_id')->where('comment.video_id', $input['video_id'])->select(['user.nick_name','user.head_portrait','comment.*'])->offset($offset)->limit($limit)->order_by('comment.created_at', 'desc')->get('comment')->result_array();
        $count = $this->db->where('video_id', $input['video_id'])->from('comment')->count_all_results();

        $data = array(
            'data' => $query,
            'total' => $count,
        );
        echo json_encode($data);
    }

核心代码