MLA-C01 Practice Test 3

Raw clickstream events land in Amazon S3 as gzip-free CSV files with 120 columns, registered as a table in the AWS Glue Data Catalog. Data scientists build training datasets by running Amazon Athena queries that select roughly 8 of those columns and filter on an event date. Every query scans the whole dataset, and the Athena bill has become the largest line item in the project. The team wants to cut the bytes each query scans without changing the queries themselves.