The 2026 Guide to Iceberg View Federation

This article provides a comprehensive guide to the Apache Iceberg View Specification, which enables portable SQL views across different query engines like Trino, Spark, Snowflake, and others. It explains how views work in Polaris, Nessie, and Gravitino catalogs, compares Iceberg native views with Snowflake Horizon views, and offers practical deployment guidance for cross-engine SQL portability. The article covers view metadata structure, versioning, dialect-specific representations, and federation across catalogs, making it a valuable resource for data engineers building multi-engine lakehouse architectures.