What is Partition Skew Ratio for ETL Data Pipelines and why it matters?
Partition skew ratio is a critical metric for measuring data distribution imbalance across partitions in ETL (Extract, Transform, Load) pipelines. It represents the ratio of the maximum bytes scanned per partition to the average bytes scanned per partition. When this ratio is high, it indicates significant partition skew challenges in data engineering workflows, which can drastically reduce performance.