Choosing the Right Iceberg Control Plane: Polaris vs. Unity Catalog vs. Cloud REST

This article explores the critical decision of selecting the right Apache Iceberg catalog control plane for modern lakehouse architecture. It compares three major options: Apache Polaris, Databricks Unity Catalog, and cloud-native REST catalogs (AWS Glue, Google Cloud BigQuery). The discussion covers decoupled interoperability via the Iceberg REST Catalog standard, architecture details, security features, access control, credential vending, and a feature matrix. It emphasizes how the catalog layer has become the key battleground for multi-engine metadata coordination, security, and cost optimization in data engineering.