What is Unity Catalog?

    Who this is for:

    Architecture / Concept Overview: What is Unity Catalog?

    Unity Catalog sits as the governance layer across all Databricks compute engines and workspaces, enforcing a single permission model regardless of whether users access data via SQL warehouses, notebooks, jobs, or ML endpoints.

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    *Figure 1 — Unity Catalog governs data access uniformly across all compute engines, enforcing one permission model everywhere.*

    Unity Catalog replaces the fragmented legacy approach where each workspace maintained its own Hive metastore.

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    *Figure 2 — Legacy Hive metastore fragmentation versus Unity Catalog's unified governance model.*

    Key Terms

    Prerequisites and Setup

    • A Databricks account (Premium or Enterprise tier)
    • Account admin role for initial metastore setup
    • Cloud storage for managed storage (S3 bucket, ADLS container, or GCS bucket)
    • An identity provider for user and group synchronisation (Azure AD, Okta, OneLogin, etc.)

    Step-by-Step Implementation

      Configuration Reference

      What is Unity Catalog? configuration options
      CapabilityDescriptionRequires
      Three-level namespacecatalog.schema.object addressingUnity Catalog enabled
      Fine-grained access controlGRANT/REVOKE at any levelAccount admin or object owner
      Row filtersRow-level security via SQL functionsPremium tier
      Column masksColumn-level masking via SQL functionsPremium tier
      Data lineageAutomatic table and column lineageUnity Catalog enabled
      Data quality monitoringAnomaly detection and profilingLakehouse Monitoring
      System tablesAudit, billing, lineage tablesAccount admin
      Delta SharingCross-org data sharingUnity Catalog enabled

      Monitoring, Cost, and Security Considerations

      Common Pitfalls and Recommended Patterns

        Frequently Asked Questions