Thanks Szehon. The reason for the difference is that the proposal in the Google doc is based on a new MV model, hence, new metadata fields and a new metadata model were being introduced (with types, optionality, etc). With reusing the table and view objects, we are not changing the existing metadata of either table or view spec but rather introduce new properties and formalize them to express materialized views. This would be the answer to most of the questions you posted on the PR (besides some naming questions, which I think should be straightforward).
With that fundamental difference, we cannot lift and shift what is in the doc to any PR. Further, having consensus on separate table and view objects contradicts with the point being made on having consensus on the doc. We might have had agreements on some elements, but definitely not on the whole doc, proven by the follow ups (also as a community, not individuals). Therefore: we need a new space to discuss the separate table and view properties. Is the question whether to: 1- Create a new doc 2- Create a new PR? I feel a PR is the most effective way, especially given the fact that we discussed the topic a lot by now. If we agree, we can continue the discussion on the PR, else, we can create a doc. Thanks, Walaa. On Thu, May 9, 2024 at 4:39 PM Szehon Ho <szehon.apa...@gmail.com> wrote: > Thanks Walaa for driving it forward, looking forward to thinking about > implementation of Materialized Views. > > I see Jan's point, the PR spec change is similar but does not seem to be > completely aligned with the Draft Spec in the design doc: > https://docs.google.com/document/d/1UnhldHhe3Grz8JBngwXPA6ZZord1xMedY5ukEhZYF-A/ > . I left my comments on PR of those sections with the links to the > difference. I think most of those Draft Spec proposal is still applicable > after the decision to have separate Table and View objects It will be > interesting to at least see drill a bit further why we did not choose the > approach in the Draft Spec and chose another way. > > Thanks > Szehon > > On Wed, May 8, 2024 at 4:48 AM Jan Kaul <jank...@mailbox.org.invalid> > wrote: > >> Well, everybody that actively contributed to the discussion on the >> original google doc was in consensus. That's why I brought up the topic at >> the Community Sync on the 2024-02-14 (https://youtu.be/uAQVGd5zV4I?t=890) >> to raise the awareness of the broader community. After which the discussion >> about the storage model started. I don't think that the discussion about a >> single aspect of a proposal should invalidate all other aspects of the >> proposal. >> >> Regardless, the state of the proposal from the original google doc >> contains a lot of valuable contributions from Micah, Szehon, Jack, Dan, >> yourself and others and it should at least provide the basis for any >> further discussion. I don't think it's effective to start with a completely >> different design because we are bound to have the same discussions all over >> again. >> >> Thanks, Jan >> On 08.05.24 12:11, Walaa Eldin Moustafa wrote: >> >> The only consensus the community had was on the object model through the >> most recent voting thread [1]. This kind of consensus was not present >> during the doc discussions, and this should be evident from the fact the >> last doc state listed 5 alternatives with no particular conclusion. I am >> not quite sure what type of consensus we are referring to here given all >> the follow up discussions, alternatives, etc. >> >> Due to the separate object model, the PR is fundamentally different from >> the doc in the sense it does not propose a new metadata model but rather >> formalizes some new table and view properties related to MVs. That is also >> one reason there are no repeated discussions. That said, if you feel there >> is a repeated discussion (which I do not see so far), it would be best to >> link the relevant discussion from the doc in a comment. >> >> Happy to move the discussion elsewhere if there is sufficient support for >> this idea, but as things stand, I do not see this as an efficient way to >> make progress. It sounds we have been re-emphasizing the same points in the >> last two replies, so I will let others chime in at this point. >> >> [1] https://lists.apache.org/thread/rotmqzmwk5jrcsyxhzjhrvcjs5v3yjcc >> >> Thanks, >> Walaa. >> >> >> On Wed, May 8, 2024 at 2:31 AM Jan Kaul <jank...@mailbox.org.invalid> >> <jank...@mailbox.org.invalid> wrote: >> >>> The original google doc >>> <https://docs.google.com/document/d/1UnhldHhe3Grz8JBngwXPA6ZZord1xMedY5ukEhZYF-A/edit?usp=sharing> >>> discussed multiple aspects of the Materialized View spec. One was the >>> storage model while others were related to the metadata. After we (Micah, >>> Szehon, you, me) reached consensus in the google doc, Jack raised his >>> concern about the storage model and the long discussion about the storage >>> model started. Now we truly reached consensus about the storage model, >>> which is now also reflected in the google doc. All other aspects from the >>> google doc about the metadata weren't questioned and still represent the >>> consensus. >>> >>> I would like to *avoid repeating the discussions* in your PR that we >>> already had in the google doc. Especially since we reached consensus which >>> took a considerable amount of time. >>> >>> Thanks, Jan >>> On 08.05.24 10:21, Walaa Eldin Moustafa wrote: >>> >>> Thanks Jan. I think we moved on to more alignment steps beyond that doc >>> a while ago. After that doc, we have discussed the topic further in 2 dev >>> list threads and one more doc >>> <https://docs.google.com/document/d/1zg0wQ5bVKTckf7-K_cdwF4mlRi6sixLcyEh6jErpGYY/edit?pli=1> >>> (with strictly two options for the storage model to consider). Moreover, >>> the original doc grew to 14 pages long with one section comparing 5 design >>> alternatives, which made things harder to reach consensus. The lack of >>> consensus is what partly led up to the subsequent discussions and call for >>> a more focused approach to reach consensus. If we already have a consensus >>> on the storage model (separate tables and views), I think we should take >>> things further and have continued focused discussions on the specific >>> metadata in the form of a PR. I have included all previous discussions >>> including the original doc and issue as references in the PR description. >>> Please let me know if this works. Happy to hear others' thoughts on the >>> best way to move forward. >>> >>> Thanks, >>> Walaa. >>> >>> >>> On Wed, May 8, 2024 at 12:56 AM Jan Kaul <jank...@mailbox.org.invalid> >>> <jank...@mailbox.org.invalid> wrote: >>> >>>> Thanks Walaa for trying to move things along. However I don't think >>>> it's a good idea to start a separate discussion about the metadata for >>>> materialized views because we already had this discussion and reached >>>> consensus in this google doc: >>>> >>>> >>>> https://docs.google.com/document/d/1UnhldHhe3Grz8JBngwXPA6ZZord1xMedY5ukEhZYF-A/edit?usp=sharing >>>> >>>> Once the draft is finalized we can adopt the PR to reflect the >>>> consensus from the google doc. >>>> >>>> Best wishes, >>>> >>>> Jan >>>> On 07.05.24 19:11, Walaa Eldin Moustafa wrote: >>>> >>>> Thanks Steven. I feel it is needed so the MV spec is not scattered >>>> across the table and view spec pages. We may add a reference in each >>>> respective properties section. >>>> >>>> On Tue, May 7, 2024 at 10:04 AM Steven Wu <stevenz...@gmail.com> wrote: >>>> >>>>> Walaa, thanks for initiating the next step. >>>>> >>>>> With the agreed model of separate view and storage table, I am >>>>> wondering if a separate materialized view spec page is needed. E.g., the >>>>> new view metadata (view-materialized and view-storage-table) is probably >>>>> good to be added to the view page directly to avoid information >>>>> scattering. >>>>> The same can be said about the storage table metadata. >>>>> >>>>> We may keep the separate materialized view page to document >>>>> motivation, freshness semantics, etc.. >>>>> >>>>> On Mon, May 6, 2024 at 10:58 PM Walaa Eldin Moustafa < >>>>> wa.moust...@gmail.com> wrote: >>>>> >>>>>> Hi Everyone, >>>>>> >>>>>> Thanks again for participating in the modeling discussion [1]. Since >>>>>> the outcome of this discussion was to model materialized views as >>>>>> separate >>>>>> objects, an Iceberg view and a table, I think the next step should be >>>>>> discussing the metadata details for each object. I have created a PR >>>>>> https://github.com/apache/iceberg/pull/10280 with an initial spec >>>>>> improvement. Please feel free to review it and leave feedback there. >>>>>> >>>>>> [1] https://lists.apache.org/thread/rotmqzmwk5jrcsyxhzjhrvcjs5v3yjcc >>>>>> >>>>>> Thanks, >>>>>> Walaa. >>>>>> >>>>>>
