Athena and ETL plans are inefficient for a large table.
Collect value-distribution and NULL metadata so the optimizer and quality review can use it.
Which feature is most appropriate?
Collect Glue Data Catalog Column Statistics such as distinct values and NULL counts.
Detailed explanation
API activity is unrelated to NULL values in a data column.
API activity is unrelated to NULL values in a data column.
File timestamps do not describe column distributions or NULL rates.
File timestamps do not describe column distributions or NULL rates.
Column statistics describe data distribution and support query planning and quality analysis.
Column statistics describe data distribution and support query planning and quality analysis.
Permission-use history is not a statistic about data values.
Permission-use history is not a statistic about data values.
Check official documentation
Compare the following points with the official documentation.
AWS Glue Data Catalog Column Statistics、AnalyzeTable、統計の公式説明を確認する。
What to confirm
オブジェクト時刻・権限利用・監査イベントと列統計を区別できる。
Key points
- Column Statistics
- NDV
- NULL count
- Query optimizer
Notes
- Environment: AWS公式DEA-C01試験ガイドと各サービスの公式ドキュメントの確認
- Confirm current AWS service behavior in the official DEA-C01 documentation.
Foundation review
Statistics freshness
Data distribution changes can make old statistics misleading, so refresh policy matters.
Quality and performance
The same statistics can support both query planning and data-quality investigation.