I prefer to keep the full chain.

Consider this scenario:
1st DEFINER => 2nd DEFINER => TABLE

When a user has access only to the outer view and the load table endpoint
is called, the following authorizations conditions must be ensured:

   1. Owners of the DEFINER views still have access to their referenced
   objects
   2. The querying User has access to his entrypoint - the 1st DEFINER View

If the load table endpoint receives only the immediate parent in
referenced-by, we lose critical information for check (2). This means the
request data alone—even if trusted—is insufficient to make a complete
authorization decision unless the server internally correlates the call to
the 2nd DEFINER load with the load table request, as we can't trace it back
to the 1st DEFINER otherwise. To make this work consistently we would
require referenced-by also for the load View endpoint.

Additionally, knowing the user's entry point is valuable for auditing
purposes, particularly in DEFINER-heavy implementations.

I kind of disagree that postgres DEFINER views don't require deeply nested
context.

Postgres just handles this chain internally:
1. User is allowed to query 1st DEFINER
2. thus 2nd DEFINER may be used to respond to the query
3. thus TABLE maybe used to respond to the query
But propagating this trust relationship in Icebeberg REST is more complex
as objects are queried individually, so we can't just validate the full
plan, but instead need to be able to validate access to each individual
component it requires.

Best,
Christian

On Mon, 2 Feb 2026 at 19:44, Russell Spitzer <[email protected]>
wrote:

> Just to re-up my comments from the discussion.
>
> I'm in favor of Immediate Parent only. Full chain seems to be for
> situations where we want to be able to "override" the security
> definition of an inner nested view. For users who want to
> do this, I would encourage them to just make a brand new definer view
> without referencing the "invoker" view.
>
> For example
>
> DEFINER => INVOKER => TABLE
>
> The "definer" should not be able to remove the "invoked" nature of access
> to the table. If a user really
> wants that behavior they should construct
>
> DEFINER (Combined with INVOKER SQL) => TABLE
>
> I'd rather we didn't encourage more complicated constructions
>
> On Mon, Feb 2, 2026 at 12:34 PM Prashant Singh <[email protected]>
> wrote:
>
>> Hi everyone,
>>
>> I’m currently working on passing additional context via the referenced-by
>> parameter in loadTable calls. This is a foundational step toward
>> enabling catalogs to make authorization decisions based on query execution
>> context.
>>
>> While the broader trust relationships and AuthZ constructs are outside
>> the scope of IRC, I’d like to align on the level of detail we should
>> provide. Specifically: *Should we send the entire view reference chain,
>> or only the immediate parent view on nested views?*
>>
>> The following are trade-offs:
>>
>>    -
>>
>>    *Full Chain:* Provides maximum flexibility for the server to make
>>    complex AuthZ decisions but increases client-side overhead for tracking
>>    nested references.
>>    -
>>
>>    *Immediate Parent:* Simpler for the client to implement but provides
>>    limited context for sophisticated authorization policies.
>>
>> *Prior Art & Research:* As noted in this discussion
>> <https://github.com/apache/iceberg/pull/13810#discussion_r2747121401>
>> (thanks Ryan and Russell), Postgres handles this via DEFINER (owner
>> permissions) and INVOKER (query permissions) without requiring deeply
>> nested context. My research into other engines hasn't yielded a standard
>> "gold level" approach yet, as some platforms simply restrict nested view
>> complexity.
>>
>> I’d love to hear your thoughts on which approach aligns better.
>>
>> Best regards,
>>
>> Prashant Singh
>>
>

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