---
title: "Interoperability between Unity Catalog and Google BigQuery via catalog federation"
description: "Databricks and Google Cloud announce bidirectional catalog federation that lets customers access the same data from Unity Catalog or BigQuery without duplication. The interoperability uses Apache Iceberg REST catalog APIs, enabling both platforms to read and write the same tables through a common open interface. Google Cloud's catalog federation is in preview for reading Unity Catalog-managed tables from BigQuery, while Google Cloud's Lakehouse federation is in private preview for Databricks users to govern and read foreign Iceberg tables. Unity Catalog's policies, fine-grained access controls, and lineage tracking apply to federated data, and users can query it with Genie using natural language. The announcement positions open standards as a path to interoperability across data platforms and previews future catalog metadata exchange through Iceberg REST catalog APIs."
---

# Interoperability between Unity Catalog and Google BigQuery via catalog federation

[Databricks](https://yomu.fyi/company/databricks) · John Spencer, Jason Reid · Apr 29, 2026

**Type:** Announcement

## Summary

Databricks and Google Cloud announce bidirectional catalog federation that lets customers access the same data from Unity Catalog or BigQuery without duplication. The interoperability uses Apache Iceberg REST catalog APIs, enabling both platforms to read and write the same tables through a common open interface. Google Cloud's catalog federation is in preview for reading Unity Catalog-managed tables from BigQuery, while Google Cloud's Lakehouse federation is in private preview for Databricks users to govern and read foreign Iceberg tables. Unity Catalog's policies, fine-grained access controls, and lineage tracking apply to federated data, and users can query it with Genie using natural language. The announcement positions open standards as a path to interoperability across data platforms and previews future catalog metadata exchange through Iceberg REST catalog APIs.

## Context

The announcement addresses interoperability between Unity Catalog, BigQuery, and Google Cloud’s Lakehouse, allowing access to shared table data without duplication while extending governance across federated data estates.

## Approach / What changed

The integration uses Apache Iceberg REST catalog APIs. BigQuery users can read Unity Catalog-managed tables through catalog federation in preview, while Databricks users can connect to Google Cloud’s Lakehouse and mount foreign Iceberg tables through a private preview of Lakehouse federation.

## Takeaways

- Apache Iceberg REST catalog APIs provide the common interface for Unity Catalog and BigQuery to read and write the same tables.
- Unity Catalog policies, fine-grained access controls, and lineage tracking apply to tables federated from Google Cloud’s Lakehouse.
- Google Cloud catalog federation is in preview, and Google Cloud Lakehouse federation for Databricks users is in private preview.

**Tags:** [Apache Iceberg](https://yomu.fyi/topic/apache-iceberg), [BigQuery](https://yomu.fyi/topic/bigquery), [Data Governance](https://yomu.fyi/topic/data-governance), [Google Cloud](https://yomu.fyi/topic/gcp), [Unity Catalog](https://yomu.fyi/topic/unity-catalog)

- Source: [Databricks](https://www.databricks.com/blog/interoperability-between-unity-catalog-and-google-bigquery-catalog-federation)
- Source URL: https://www.databricks.com/blog/interoperability-between-unity-catalog-and-google-bigquery-catalog-federation
- Ingested by Yomu: 2026-08-31T03:40:43.981Z

[Read original post](https://www.databricks.com/blog/interoperability-between-unity-catalog-and-google-bigquery-catalog-federation)