Hi Everyone, Looking forward to keeping up the momentum and closing out the MV spec as well. I’m hoping we can proceed to a vote next week.
Here is a summary in case that helps. The proposal outlines a strategy for handling table identifiers in Iceberg view metadata, with the goal of ensuring correctness, portability, and engine compatibility. It recommends resolving table identifiers at read time (late binding) rather than creation time, and introduces UUID-based validation to maintain identity guarantees across engines, or sessions. It also revises how default-catalog and default-namespace are handled (defaulting both to the session context if not explicitly set) to better align with engine behavior and improve cross-engine interoperability. Please let me know your thoughts. Thanks, Walaa. On Wed, Apr 16, 2025 at 2:03 PM Walaa Eldin Moustafa <wa.moust...@gmail.com> wrote: > Thanks Eduard and Sung! I have addressed the comments. > > One key point to keep in mind is that catalog names in the spec refer to > logical catalogs—i.e., the first part of a three-part identifier. These > correspond to Spark's DataSourceV2 catalogs, Trino connectors, and similar > constructs. This is a level of abstraction above physical catalogs, which > are not referenced or used in the view spec. The reason is that table > identifiers in the view definition/text itself refer to logical catalogs, > not physical ones (since they interface directly with the engine and not a > specific metastore). > > Thanks, > Walaa. > > > On Wed, Apr 16, 2025 at 6:15 AM Sung Yun <sungwy...@gmail.com> wrote: > >> Thank you Walaa for the proposal. I think view portability is a very >> important topic for us to continue discussing as it relies on many >> assumptions within the data ecosystem for it to function like you've >> highlighted well in the document. >> >> I've added a few comments around how this may impact the permission >> questions the engines will be asking, and whether that is the desired >> behavior. >> >> Sung >> >> On Wed, Apr 16, 2025 at 7:32 AM Eduard Tudenhöfner < >> etudenhoef...@apache.org> wrote: >> >>> Thanks Walaa for tackling this problem. I've added a few comments to get >>> a better understanding of how this will look like in the actual >>> implementation. >>> >>> Eduard >>> >>> On Tue, Apr 15, 2025 at 7:09 PM Walaa Eldin Moustafa < >>> wa.moust...@gmail.com> wrote: >>> >>>> Hi Everyone, >>>> >>>> Starting this thread to resume our discussion on how to reference table >>>> identifiers from Iceberg metadata, a key aspect of the view specification, >>>> particularly in relation to the MV (materialized view) extensions. >>>> >>>> I had the chance to speak offline with a few community members to >>>> better understand how the current spec is being interpreted. Those >>>> conversations served as inputs to a new proposal on how table identifier >>>> references could be represented in metadata. >>>> >>>> You can find the proposal here [1]. I look forward to your feedback and >>>> working together to move this forward so we can finalize the MV spec as >>>> well. >>>> >>>> [1] >>>> https://docs.google.com/document/d/1-I2v_OqBgJi_8HVaeH1u2jowghmXoB8XaJLzPBa_Hg8/edit?tab=t.0 >>>> >>>> Thanks, >>>> Walaa. >>>> >>>
