Hi Prashant,

Thanks for sharing this proposal! This has been top of mind for me as well, 
since I’m working on integrating Trino with Iceberg while also supporting other 
heterogeneous engines in the ecosystem.

I agree that a change like this is necessary to enable SECURITY DEFINER views 
to correctly provision metadata for the underlying tables. That said, even if 
it’s out of scope for this document, I think it would be valuable to also 
discuss potential attack vectors. Adopters of this feature should be aware of 
the additional risk surface it introduces if there isn’t a trusted security 
contract between the client and the catalog.

I’d also support converging on a consistent metadata property convention for 
view ownership and security mode, so we have a common foundation across engines.

Curious to hear what others think.

Best,
Sung

On 2025/08/18 22:20:33 Prashant Singh wrote:
> Hi everyone,
> 
> I wanted to bring up a small but important change to how we handle view
> security in Iceberg, especially for *DEFINER* views. This change is crucial
> for ensuring views function as a secure gateway to sensitive data, where
> access is determined by the view's creator, not the user running the query.
> 
> The Problem
> 
> Currently, when a view queries a table, the loadTable request to the REST
> catalog doesn't know that it's coming from a view. It just sees the table's
> name and defaults to checking the permissions of the user running the
> query. This does not work well with the security model for *DEFINER* views
> and prevents them from working as intended.
> 
> The Proposed Solution (PR-13810
> <https://github.com/apache/iceberg/pull/13810>)
> 
> To address this, I've created a pull request that adds an optional
> loaded-via field to the loadTable request. This field will contain the
> fully qualified name of the view (e.g., my_db.secure_view) i.e namespace
> and the view name.
> 
> When the catalog sees this new field, it will know to perform the security
> check against the view's owner, not the query invoker. This small addition
> ensures that the view's security semantics are respected, and it's
> backward-compatible with existing clients.
> 
> I've also included a simple proof-of-concept (POC) to show how a client
> could implement this, along with Spark. I'm open to feedback on the
> approach, especially on how to cleanly pass the view context to the
> loadTable request, the POC is just for demonstration *POV*.
> 
> You can view the full proposal (Iceberg View Security
> <https://docs.google.com/document/d/15zgmACxue8jH8SIBAJNzZ64Mx6RTRmDv2IoH3Clc2uQ/edit?tab=t.0>)
> and for details can refer PR-13810
> <https://github.com/apache/iceberg/pull/13810>
> 
> Looking forward to your thoughts.
> 
> Best,
> Prashant Singh
> 

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