code: 124, error: MongoDB timeout. Typically this indicates the request is too expensive. :get /1.1/files {"order" "-createdAt", "returnACL" "true", "skip" "0", "limit" "20", "count" "1"}
您好，查询超时可能是数据量太大了，可以通过建立索引的方式改善。
参考文档： https://docs.leancloud.cn/sdk/start/dashboard/#%E7%BB%99%E6%9F%90%E4%B8%AA-class-%E6%95%B0%E6%8D%AE%E5%BB%BA%E7%B4%A2%E5%BC%95
