---
title: Athena Empty Logs
description: In which I wonder where all the data has gone!
slug: athena-empty-logs
lastmod: 2024-08-24
tags:
- "amazon"
- "athena"
- "aws"
- "cloud"
- "loadbalancers"
- "sql"
---
Recently, I was querying for some ALB load balancer logs. It's not something that happens too often but I was surprised to find that the query rows were empty except for the `date` column.

I quickly figured out that only logs from May 30th, 2024 and onwards were missing and after a quick comparison, realised that the log formats had changed.

Sure enough, [as noted in a banner on this page](https://docs.aws.amazon.com/athena/latest/ug/create-alb-access-logs-table.html), the ALB access log format changed adding `classification`, `classification_reason` and `conn_trace_id` fields.

Unfortunately for anyone with [AWS Athena](https://aws.amazon.com/athena/) tables, that means your pre-existing tables will likely have an out of date regex if you're using `org.apache.hadoop.hive.serde2.RegexSerDe` as your row format.

I don't believe there is any way to update this and it requires recreating each table given that Athena [doesn't support](https://docs.aws.amazon.com/athena/latest/ug/unsupported-ddl.html) altering `SERDEPROPERTIES`.

Honestly, I found this whole thing kind of disappointing and I'm not sure what prevents it from happening again in future but as mentioned, I don't personally use Athena too often to feel the pain.