Early Athena (managed prestodb by AWS) had a similar bug when measuring colunar file scans. If it touched the file, it considered the whole file instead of just

Early Athena (managed prestodb by AWS) had a similar bug when measuring colunar file scans. If it touched the file, it considered the whole file instead of just the column chunks read. If I’m not mistaken, this was a bug on presto itself, but it was a simple patch that landed on upstream a long time before we did the tests. This was the first and only time we considered using a relatively early AWS product. It was so bad that our half assed self deployed version outperformed Athena by every metric that we cared about