Skip to main content

Announcing General Availability of Hive Metastore and AWS Glue Federation in Unity Catalog

Announcing Public Preview of Hive Metastore and AWS Glue Federation in Unity Catalog

Published: March 19, 2025

Announcements4 min read

Summary

  1. Connect HMS and AWS Glue catalogs directly to Unity Catalog without manual metadata migration.
  2. Explore data from HMS and AWS Glue through a unified interface, alongside other data and AI assets in Unity Catalog.
  3. Benefit from fine-grained access controls, tagging, classification, lineage, and auditing in one place.

We’re excited to announce the General Availability of Hive Metastore (HMS) and AWS Glue Federation in Unity Catalog! This new capability enables Unity Catalog to seamlessly access and govern tables stored in Hive Metastores—whether self-hosted or hosted by Databricks—as well as AWS Glue. It represents a key milestone in our Lakehouse Federation vision, which brings external data sources including databases, data warehouses and catalogs, together under a unified governance framework with Unity Catalog. You can now effortlessly discover, query, and manage all your data from a single, centralized platform, regardless of the format and location. This not only fosters open access and collaboration across your organization but also extends data intelligence into every data source.

In this blog, we’ll explore the benefits of HMS and AWS Glue Federation, explain how it works, and provide guidance on getting started.

Why Hive Metastore and AWS Glue Federation? 

HMS has been an early standard for cataloging data for use in big data systems, and while it provides foundational functionalities, they are not ideally suited for modern data and AI workloads that demand comprehensive governance, including fine-grained access controls on rows and columns, lineage, monitoring and auditing across all data and AI assets in one place. 

Unity Catalog addresses these shortcomings by providing the industry’s only unified, open governance solution for managing all data and AI assets. It enables organizations to create an enterprise catalog that curates files, tables, ML models, AI tools, notebooks, and metrics, all governed with fine-grained access controls, lineage, monitoring, auditing, and cross-platform sharing in one solution. Over 10,000+ enterprises are now leveraging Unity Catalog to govern their data estate.

HMS and AWS Glue Federation provide significant benefits for organizations with HMS deeply embedded in their data architecture. For those with long-standing HMS or AWS Glue deployments, this capability offers a seamless path to leverage Unity Catalog's advanced features over data stored in the HMS or Glue metastore. It ensures operational continuity by enabling organizations to sustain legacy workflows while gradually upgrading existing data and workspaces to Unity Catalog.

Key benefits include:

  • Seamless integration: Connect your existing HMS and AWS Glue catalogs directly to Unity Catalog without requiring manual metadata migration.
  • Simplified data discovery: Access and explore data from HMS and AWS Glue through a unified interface, alongside all your data and AI assets in Unity Catalog.
  • Comprehensive governance: Leverage Unity Catalog's fine-grained access controls, tagging, classification, lineage, and audit capabilities on top of the data stored in HMS and AWS Glue
Utilizing HMS Federation in Unity Catalog enabled an incremental migration that minimized disruption to our customers. Our partnership with Databricks was crucial in evaluating short-term needs and long-term goals. Leveraging Unity Catalog’s capabilities early, we created a scalable and efficient data platform with improved governance and access control as part of our modernization journey 
— Praveena Edward, Lead Data Engineer, Nationwide
We have years’ worth of datasets that are cataloged in an external Hive Metastore. HMS Federation allows us to immediately benefit from Unity Catalog only features like robust access control and self-serve AI tooling through Genie Spaces, without the overhead of migrating all of these tables into Unity Catalog
— James Davidheiser, Technical Lead, Data Infrastructure, Asana

How it works

Unity Catalog now includes federation connectors for Hive Metastore (HMS) and AWS Glue, serving as a translation layer between Unity Catalog and your external metastores. These connectors let you mount entire HMS catalogs (both internal and external) or AWS Glue as foreign catalogs within Unity Catalog, making them appear as native objects. You can define fine-grained access controls, view lineage, perform audits, and query HMS or AWS Glue managed tables using the Databricks engine. The federation supports both reading and writing to tables in internal HMS within Databricks workspaces while offering read-only access for tables in external HMS and AWS Glue

With this capability, you can read all tables in HMS and AWS Glue—Parquet, Delta, and Iceberg (coming soon in Public Preview)—enabling you to access and govern all your tables seamlessly.

HMS Fed
HMS and AWS Glue Federation in Unity Catalog

Check out the video tutorial below to explore AWS Glue and HMS Federation in action.

What's new with the GA release?

The GA release comes with the following additional features:

  • Support for Hive Metastore v3.1 
  • Support for Hive Metastores hosted in a SQL Server or Postgres databases (mySQL support already provided)
  • Access to DBFS-root backed tables behind a storage firewall (Azure)
  • Support for row and column level masks on Hive tables

We’ve also added Public Preview support for reading Delta shallow clones defined in the Hive metastore, as well as Private Preview support for reading DBFS-mount backed tables across workspaces (please contact your Databricks account representative to sign up!).

Get started

By embracing Unity Catalog as the cornerstone of your Lakehouse architecture, you can unlock the power of a unified and open governance implementation that spans your entire data and AI estate.

  • Follow the HMS Federation guides ( AWS, Azure and GCP) to get started.
  • To get started with Unity Catalog, follow the Unity Catalog guides available for AWS, Azure, and GCP

Never miss a Databricks post

Subscribe to the categories you care about and get the latest posts delivered to your inbox