Question

A data engineering team runs ad hoc Athena queries against a large S3 data lake. Finance reports that Athena costs have spiked because analysts frequently run SELECT * queries that scan entire multi-terabyte tables. The team wants to enforce a hard limit on how much data any single query can scan, and automatically cancel queries that exceed that limit, without modifying the underlying tables or query patterns. Which approach meets this requirement with the least operational effort?

Accepted Answer

Configure a per-query data usage control in the Athena workgroup that cancels any query scanning more than the specified amount of data.

Answer

Create a CloudWatch alarm on the Athena BytesScannedCutoffPerQuery metric and use a Lambda function to cancel running queries.

Answer

Convert all tables to Parquet with Snappy compression so that queries scan less data automatically.

Answer

Enable an S3 bucket policy that denies GetObject requests once a daily byte-transfer threshold is reached.