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    Databricks Certified Data Engineer Professional· Lessons

    Domain 2 · Lesson 16/46

    Databricks Clean Rooms for Privacy-Preserving Collaboration

    Implement OpenSharing (D2D and Databricks-to-Open) and Clean Rooms for privacy-preserving collaboration.

    8 min read
    2.4% of exam
    2 sources
    Published 2 Oct 2026
    Docs as of 30 Sep 2026

    What you will be able to do

    • List the workspace and metastore prerequisites for using Clean Rooms
    • Describe what a clean room creates and what each collaborator can and cannot see
    • Explain the no-trust notebook approval model and how packaged clean rooms differ
    • Apply the clean room safeguards, limits and audit sources when you design a collaboration

    1.What Clean Rooms are and what they require

    Sometimes two organizations want to run a joint analysis, such as overlapping customer lists, without either side handing its raw data to the other. Databricks Clean Rooms handles this case. It combines OpenSharing with serverless compute to create an environment where several parties can work on sensitive enterprise data without direct access to each other's data.

    Because it is built on those two pieces, the prerequisites follow from them. You need a workspace enabled for serverless compute, a workspace enabled for Unity Catalog, and OpenSharing enabled on your Unity Catalog metastore. Storage location matters too, because clean rooms run on serverless compute. That compute can't reach an S3 bucket behind a storage firewall by default. You can keep the data in Databricks default storage or allow serverless access on the bucket. If the data is behind a firewall or private endpoint, SecureConnect lets clean room compute reach it without allowlisting its network.

    Checkpoint 1 of 5· Check yourself

    A workspace is enabled for Unity Catalog and serverless compute, but creating a clean room fails eligibility. Which missing prerequisite is the most likely cause?

    Sources12

    2.What a clean room creates and who sees what

    Creating a clean room creates three objects. There is a securable clean room object in your metastore and a matching one in your collaborator's metastore. In between sits the central clean room, an isolated, ephemeral environment that Databricks manages. It runs in a serverless compute plane in the cloud region chosen by the clean room's creator.

    This is where Clean Rooms uses OpenSharing differently from a normal share. The tables, volumes, views and notebooks each collaborator adds are shared with the central clean room only, never directly with the other party. Each asset is registered there under its alias. Notebook code runs inside the central room. A notebook can write output tables, which give a collaborator read-only, temporary results in their own Unity Catalog metastore to work with in their own workspace.

    Checkpoint 2 of 5· Check yourself

    How does data move between two clean room collaborators?

    Sources12

    3.The no-trust model and notebook approval

    The Clean Rooms model is described as "no-trust". Every collaborator has equal privileges, and that includes the creator, so neither party is an admin of the central clean room. Trust comes from code approval rather than from roles. You can upload a notebook yourself, but it runs only after the other collaborators approve it. In practice you run notebooks the other party uploaded, after reading the code. Running another party's notebook counts as approving it.

    Notebooks are version-controlled, and only the latest version can run. That stops someone from changing code after it has been approved. The clean rooms system table shows which notebook version ran.

    Packaged clean rooms are the exception. They use a provider-consumer model in which collaborators do not have equal privileges.

    Checkpoint 3 of 5· Exam question

    Two banks want to jointly analyze overlapping customer records without either side seeing the other's raw data, and both insist on equal control over which queries run and what results leave the environment. Select all statements that correctly describe how a Databricks Clean Room supports this requirement.(Select 3)

    Checkpoint 4 of 5· Check yourself

    Your collaborator uploads a notebook. You have not clicked an explicit approve button, but you run the notebook from your workspace. What is the effect?

    Sources1

    4.Safeguards, limits and auditing

    Beyond notebook approval, the clean room's structure is fixed once it is created. Network and audit controls cover the rest. The table below lists the rules most likely to show up in a design question.

    Clean room safeguards and limits
    RuleConsequence
    Locked after creationNo new collaborators can join an existing clean room
    Ten-collaborator limitEach clean room holds at most ten collaborators
    Any collaborator deletes itThe central clean room is void and no tasks can run for anyone
    No renamingThe name must be unique in every collaborator's metastore
    Serverless egress controlRestricting the clean room blocks access to unauthorized storage
    Cross-cloud or cross-region roomOnly tables in default storage are accessible; volumes are not

    Audit records come from three places. The clean room events system table records actions by you and your collaborators. Your account audit log records clean room actions under the clean-room service. When a collaborator changes permissions on the clean room securable in their own metastore, that change is logged under the unityCatalog service. Comments added to a clean room securable stay in the workspace where they were written and are not passed to other collaborators.

    Checkpoint 5 of 5· Check yourself

    A security team needs to find every clean room action in the account audit log. Which service name should they filter on?

    Sources1

    Exam traps

    Each one states something that sounds right. Open it to see what is actually true.

    1. 1.The collaborator who creates a clean room is its administrator and can run their own notebooks without anyone else's approval.Why is that wrong?

      In a standard clean room all collaborators have equal privileges, the creator included. A notebook you upload yourself must be approved by the others before it runs.

      Covered in The no-trust model and notebook approval

    2. 2.Every clean room follows the equal-privilege no-trust model.Why is that wrong?

      Packaged clean rooms use a provider-consumer model instead, so collaborators' privileges are not equal.

      Covered in The no-trust model and notebook approval

    3. 3.A volume in default storage can be used in any clean room, whatever region the central clean room is in.Why is that wrong?

      Volumes in default storage are accessible only when the central clean room is in the same cloud and region. In a cross-cloud or cross-region room, only tables are accessible.

      Covered in Safeguards, limits and auditing

    Sources

    Every claim above is drawn from one of these pages, quoted as it was written on the date shown.

    1. 1.
      “a secure and privacy-protecting environment where multiple parties can work together on sensitive enterprise data without direct access to each other's data”
      ↩︎ What Clean Rooms are and what they require
      “enable SecureConnect so that clean room serverless compute can access it without allowlisting the clean room compute's network”
      ↩︎ What Clean Rooms are and what they require
      “are shared with the central clean room only, using OpenSharing”
      ↩︎ What a clean room creates and who sees what
      “Notebooks can also generate output tables that let your collaborator temporarily save read-only output to their Unity Catalog metastore”
      ↩︎ What a clean room creates and who sees what
      “While you can upload a notebook to yourself, it must be approved by the other collaborators before running.”
      ↩︎ The no-trust model and notebook approval
      “Only the most recent version of a notebook can be run.”
      ↩︎ The no-trust model and notebook approval
      “Neither party has admin privileges.”
      ↩︎ The no-trust model and notebook approval
      “After a clean room is created, it is locked down to prevent new collaborators from joining the clean room.”
      ↩︎ Safeguards, limits and auditing
      “If any collaborator deletes the clean room, the central clean room is void and no clean room tasks can be run by any user.”
      ↩︎ Safeguards, limits and auditing
      “Each clean room is limited to ten collaborators.”
      ↩︎ Safeguards, limits and auditing
      “you can use serverless egress control to manage outbound network connections”
      ↩︎ Safeguards, limits and auditing
      “All collaborators in a no-trust clean room have equal privileges, including the creator of the clean room.”
      ↩︎ Exam trap 1
      “They use a provider-consumer model in which collaborators do not have equal privileges.”
      ↩︎ Exam trap 2
      “In a cross-cloud or cross-region clean room, only tables in default storage are accessible; volumes are not.”
      ↩︎ Exam trap 3
      “OpenSharing enabled for your Unity Catalog metastore.”
      ↩︎ Checkpoint
      “they can see column names and column types, and they can run approved notebook code that operates over the data assets”
      ↩︎ Prediction
      “Clean rooms use OpenSharing to share data securely to the clean room, but not between participants.”
      ↩︎ Checkpoint
      “If you run a notebook added by another party, you implicitly approve the code.”
      ↩︎ Checkpoint
      “Clean room actions are also recorded in your account's audit log under the service clean-room.”
      ↩︎ Checkpoint
    2. 2.
      “Clean Rooms, a secure and privacy-protecting environment where multiple parties can work together on sensitive enterprise data”
      ↩︎ What Clean Rooms are and what they require
      “Enable OpenSharing on the Unity Catalog metastore that manages the data.”
      ↩︎ What Clean Rooms are and what they require
      “OpenSharing is also the basis for Databricks Marketplace, an open forum for exchanging data products, and Clean Rooms”
      ↩︎ What a clean room creates and who sees what

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