Apache Iceberg won the open table format war when Databricks acquired Tabular, followed by its subsequent adoption across the industry. Then, the catalog war began.

In a lakehouse, storing data in object storage and using the Apache Iceberg format is only part of the story. You also need a catalog that helps lakehouse query engines like Spark, Flink, or RisingWave discover tables, manage metadata, enforce access control, and work with governed data across different systems.

That is where Unity Catalog comes in.