Can we keep it simple for v1, as one location field is enough for today’s use cases? And we can revisit multi-location support when there’s real demand.
The current API spec already implies that a table’s location is immutable, there’s no “alter location” call. I’m fine leaving it implicit, but we could add an explicit note to make that clear if it helps avoid confusion. Yufei On Wed, May 21, 2025 at 4:36 PM Eric Maynard <eric.w.mayn...@gmail.com> wrote: > No two tables globally can have a location overlap? That’s a stricter > requirement than we have for even Iceberg tables and doesn’t sound correct. > > Similarly, the restriction that you can’t change location is stricter than > what we have for Iceberg. > > Finally, I’m still not sure what the problem is with having multiple > locations. Again, we already track multiple locations for Iceberg. > > On Thu, May 22, 2025 at 12:32 AM yun zou <yunzou.colost...@gmail.com> > wrote: > > > Hi All, > > > > Want to summarize the thread here: > > > > For generic tables, we will add a `location` key to help cross engine > > sharing and future support for credential vending. > > > > Here is a description about this `location` key and corresponding > > restrictions and responsibilities: > > - `location`(OPTIONAL): table root location in URI format. For example: > > s3://<my-bucket>/path/to/table. > > - The table root location is a location that includes all files for the > > table. > > - Clients (engines) are responsible to make sure all files are written > > under the configured location. > > - A table with multiple root locations (i.e. containing files that are > > outside the configured root location) is not compliant with the current > > generic table support in Polaris. > > - No two tables can have the same or overlapped location, otherwise, a > > ForbiddenException will be thrown on creation. > > - If no location is provided, clients or users are responsible to > manage > > the location and location related concerns such as path conflict check > etc. > > - The location configuration can not be updated once the table is > > created. > > > > This description will be added into the spec. In order to help non-API > > users to discover the information easily, we will also get a site page to > > describe the support > > for Generic Table and key fields. > > > > Best Regards, > > Yun > > > > On Mon, May 19, 2025 at 11:16 PM yun zou <yunzou.colost...@gmail.com> > > wrote: > > > > > Hi Dmitri, > > > > > > " I do not think those doc comments provide enough visibility to ensure > > > that the key information > > > is received by users, unless they are dealing directly with the API" > > > -- Yeah, I agree those information may not be visible enough for users > > who > > > don't directly work with APIs. > > > However, I think just having one page for "location" might be a little > > bit > > > overkill. Given that generic table API support is > > > a new catalog capabilities that Polaris added which is not IRC, I think > > it > > > might worth having a more general page to > > > describe the Polaris Generic Table support and describe some of the > > > critical fields like *location*. > > > I think we should have the description in the spec also, so that things > > > could be clear for API users. > > > > > > Please let me know what you think. > > > > > > Best Regards, > > > Yun > > > > > > On Mon, May 19, 2025 at 4:22 PM Dmitri Bourlatchkov <di...@apache.org> > > > wrote: > > > > > >> I believe the Open API spec and the definition of "location" are > > slightly > > >> different concerns. > > >> > > >> The former is about the API used to obtain information about Generic > > >> Tables. > > >> > > >> The latter is about the interpretation of that information. One can > > think > > >> of the location > > >> value being handled / transferred beyond the immediate Polaris client, > > in > > >> which case > > >> is loses its connection to the API, but does not lose its meaning as a > > >> location of a > > >> Generic Table. > > >> > > >> Also, I think that Open API doc comments are too low-level and too > > obscure > > >> for > > >> people who will work with processing actual Generic Table files. I do > > not > > >> think > > >> those doc comment provide enough visibility to ensure that the key > > >> information > > >> is received by users, unless they are dealing directly with the API. > > >> > > >> That said, if you prefer to keep the finer points about Generic Table > > >> locations in the > > >> Open API spec, I'd be fine with that. > > >> > > >> Cheers, > > >> Dmitri. > > >> > > >> On Mon, May 19, 2025 at 6:46 PM yun zou <yunzou.colost...@gmail.com> > > >> wrote: > > >> > > >> > Hi Dmitri, > > >> > > > >> > Thanks for the detailed explanation, I definitely agree we need to > > call > > >> out > > >> > those restrictions and compliance in our Spec. > > >> > > > >> > As for the documentation, Polaris today already publishes the API > > spec, > > >> if > > >> > you go to page https://polaris.apache.org/in-dev/unreleased/, > > >> > and click on the Catalog API Spec, it will lead you to the published > > >> Spec, > > >> > which contains all description in the Spec. > > >> > That basically means we have both published doc and spec code, and > the > > >> > single source of truth is the description in the doc. > > >> > or do you think we should have an extra page for the Generic Table > API > > >> > spec? > > >> > > > >> > Best Regards, > > >> > Yun > > >> > > > >> > On Mon, May 19, 2025 at 3:20 PM Yufei Gu <flyrain...@gmail.com> > > wrote: > > >> > > > >> > > > > > >> > > > * Clients (engines) are responsible for writing files only under > > the > > >> > > > specified location. > > >> > > > > >> > > It's nice to have a doc like that. But the open API spec is *the* > > >> place > > >> > to > > >> > > define the behavior of client and server, and how they interact > with > > >> each > > >> > > other. Just as we said before, spec change is recommended to have > a > > ML > > >> > > discussion. > > >> > > > > >> > > * A table, whose files exist outside the declared location, is not > > >> > > > compliant with the Polaris' definition for a Generic Table. > > >> > > > > >> > > I'm not sure we should go that far. "location" is an optional > field. > > >> It's > > >> > > just some features like credential vending that don't work if > > >> "location" > > >> > is > > >> > > missing. > > >> > > > > >> > > Yufei > > >> > > > > >> > > > > >> > > On Mon, May 19, 2025 at 2:59 PM Dmitri Bourlatchkov < > > di...@apache.org > > >> > > > >> > > wrote: > > >> > > > > >> > > > As I commented in my other recent email, I think by introducing > a > > >> > > > "location" property Polaris enters the realm of table format > > specs. > > >> > > > > > >> > > > This is fine, from my POV, however, since Polaris is the > defining > > >> > project > > >> > > > behind that property, I believe Polaris should provide a more > > >> > definitive > > >> > > > description of the meaning and intended processing of that > > property. > > >> > > > > > >> > > > To repeat myself, I think the Open API spec defines only the API > > for > > >> > > > obtaining the location. We need a place to define what this > > location > > >> > > means. > > >> > > > I do not insist on calling this a "spec" for Generic Tables, > but I > > >> > think > > >> > > it > > >> > > > deserves a separate page in Polaris docs, where it would be > > defined > > >> > with > > >> > > > more rigor. > > >> > > > > > >> > > > Specifically, I think we need to call out that: > > >> > > > * The location is a base URI (essentially prefix) for all files > > in a > > >> > > > generic table. > > >> > > > * Clients (engines) are responsible for writing files only under > > the > > >> > > > specified location. > > >> > > > * A table, whose files exist outside the declared location, is > not > > >> > > > compliant with the Polaris' definition for a Generic Table. > > >> > > > > > >> > > > By extension, I think we ought to describe other existing > > properties > > >> > too. > > >> > > > > > >> > > > WDYT? > > >> > > > > > >> > > > Thanks, > > >> > > > Dmitri. > > >> > > > > > >> > > > On Mon, May 19, 2025 at 5:39 PM yun zou < > > yunzou.colost...@gmail.com > > >> > > > >> > > > wrote: > > >> > > > > > >> > > > > Hi Dmitri, > > >> > > > > > > >> > > > > I think for Iceberg, we all agreed that there can be multiple > > >> > > locations, > > >> > > > > and I definitely agree with Russel that the extension > > >> > > > > should be done with the IRC endpoints. The Generic Table APIs > > are > > >> > > > designed > > >> > > > > for non-Iceberg table usage today, and > > >> > > > > We still want Iceberg table usage to go through the IRC > endpoint > > >> to > > >> > > have > > >> > > > > full IRC support. > > >> > > > > > > >> > > > > As for the following point > > >> > > > > "a more strict spec for that (define where file should and > > should > > >> not > > >> > > > go)" > > >> > > > > Are you referring that Polaris need to generate a location for > > the > > >> > > table > > >> > > > to > > >> > > > > use, if that is the case, I don't think engines > > >> > > > > respects that today. The table locations are either generated > by > > >> the > > >> > > > engine > > >> > > > > or specified by the user. > > >> > > > > Or are you referring that we should have something like > Iceberg > > >> that > > >> > we > > >> > > > > should have an allowed location and do a > > >> > > > > validation to make sure the location is under the allowed > > >> location? > > >> > > Would > > >> > > > > you mind elaborate more on this point? > > >> > > > > > > >> > > > > Best Regards, > > >> > > > > Yun > > >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > On Mon, May 19, 2025 at 1:45 PM Russell Spitzer < > > >> > > > russell.spit...@gmail.com > > >> > > > > > > > >> > > > > wrote: > > >> > > > > > > >> > > > > > Yeah I think Iceberg and Hive are the only ones trying to > make > > >> life > > >> > > > > > difficult, that I think > > >> > > > > > we should also cover but in changes to the Iceberg Spec. > Hive > > >> can > > >> > > just > > >> > > > > stay > > >> > > > > > how it is ... > > >> > > > > > > > >> > > > > > On Mon, May 19, 2025 at 2:59 PM Dmitri Bourlatchkov < > > >> > > di...@apache.org> > > >> > > > > > wrote: > > >> > > > > > > > >> > > > > > > For context: my locations concerns are rooted in Nessie's > > >> > > experience > > >> > > > > > where > > >> > > > > > > we often get problem reports related to files being > outside > > >> the > > >> > > > > declared > > >> > > > > > > Iceberg metadata location. > > >> > > > > > > > > >> > > > > > > Example: > > >> > > > > > > > > >> > > > > > > > > >> > > > > > > > >> > > > > > > >> > > > > > >> > > > > >> > > > >> > > > https://github.com/projectnessie/nessie/issues/10817#issuecomment-2887329227 > > >> > > > > > > > > >> > > > > > > I'm ok going with a single location for generic tables, > but > > I > > >> > think > > >> > > > > > Polaris > > >> > > > > > > needs to have a more strict spec for that (define where > file > > >> > should > > >> > > > and > > >> > > > > > > should not go) because polaris owns this spec. Polaris > ought > > >> to > > >> > > > define > > >> > > > > > what > > >> > > > > > > complies with the spec and what does not. Having a proper > > >> spec is > > >> > > > > > essential > > >> > > > > > > to ensure a mutual understanding of all parties dealing > with > > >> > > Generic > > >> > > > > > > Tables. > > >> > > > > > > > > >> > > > > > > Open API yaml comments are not sufficient, IMHO. I'd > prefer > > to > > >> > > have a > > >> > > > > > > dedicated doc page to define expectations and compliance. > > >> > > > > > > > > >> > > > > > > Thanks, > > >> > > > > > > Dmitri. > > >> > > > > > > > > >> > > > > > > > > >> > > > > > > On Mon, May 19, 2025 at 2:17 PM Russell Spitzer < > > >> > > > > > russell.spit...@gmail.com > > >> > > > > > > > > > >> > > > > > > wrote: > > >> > > > > > > > > >> > > > > > > > The only multiple locations table formats I'm currently > > >> aware > > >> > of > > >> > > > are > > >> > > > > > Hive > > >> > > > > > > > (partitions can live wherever) and Iceberg. > > >> > > > > > > > > > >> > > > > > > > I think for Delta, Hudi, LanceDB, Paimon and File based > > >> tables > > >> > > > they > > >> > > > > > all > > >> > > > > > > > have to live in the root location. I'm not sure of any > > other > > >> > > "file" > > >> > > > > > based > > >> > > > > > > > tables where this would be an issue but I'd love to know > > if > > >> > > someone > > >> > > > > > else > > >> > > > > > > > has ideas. I think with the rise in credential vending, > > >> > splitting > > >> > > > > > things > > >> > > > > > > > amongst multiple prefixes is becoming less common. I > don't > > >> > oppose > > >> > > > > doing > > >> > > > > > > an > > >> > > > > > > > array of locations but it may be enough to just leave > this > > >> as > > >> > an > > >> > > > > > > extension > > >> > > > > > > > later. (Support location or locations) > > >> > > > > > > > > > >> > > > > > > > On Wed, May 7, 2025 at 8:52 PM yun zou < > > >> > > yunzou.colost...@gmail.com > > >> > > > > > > >> > > > > > > wrote: > > >> > > > > > > > > > >> > > > > > > > > Hi Dmitri, > > >> > > > > > > > > > > >> > > > > > > > > If it's not "all" is it not strong enough for a spec, > > >> IMHO. > > >> > If > > >> > > > some > > >> > > > > > > > tables > > >> > > > > > > > > have multiple base locations how is Polaris going to > > deal > > >> > with > > >> > > > > them? > > >> > > > > > > > > > > >> > > > > > > > > Sorry, when I say most of them, it was because I > haven't > > >> > tested > > >> > > > all > > >> > > > > > of > > >> > > > > > > > them > > >> > > > > > > > > (I only tested Delta and CSV before). > > >> > > > > > > > > However, if Unity Catalog is only taking one > location, I > > >> > think > > >> > > > that > > >> > > > > > is > > >> > > > > > > a > > >> > > > > > > > > strong enough proof that > > >> > > > > > > > > one location is enough today. > > >> > > > > > > > > > > >> > > > > > > > > It is also more natural to start with one location, > and > > if > > >> > > there > > >> > > > > are > > >> > > > > > > use > > >> > > > > > > > > cases that > > >> > > > > > > > > require support for multiple locations later, we can > > move > > >> on > > >> > to > > >> > > > V2 > > >> > > > > > spec > > >> > > > > > > > to > > >> > > > > > > > > support multiple > > >> > > > > > > > > tables locations. > > >> > > > > > > > > > > >> > > > > > > > > We're making a specification for Polaris. I do not > think > > >> it > > >> > is > > >> > > > > > > sufficient > > >> > > > > > > > > to say we'll do the same as other (unspecified ATM) > > >> catalogs. > > >> > > > > > > > > If we want to migrate users from other Catalog > services > > to > > >> > > > Polaris > > >> > > > > > > > (through > > >> > > > > > > > > federation), then Polaris will need to > > >> > > > > > > > > provide corresponding capabilities. For example, > Unity > > >> > Catalog > > >> > > > > > storage > > >> > > > > > > > > location is a URI representation, when entity > > >> > > > > > > > > are federated from Unity Catalog, we will need to be > > able > > >> to > > >> > > > handle > > >> > > > > > the > > >> > > > > > > > URI > > >> > > > > > > > > location. > > >> > > > > > > > > If URI representation is a common standard that has > been > > >> > > accepted > > >> > > > > by > > >> > > > > > > > other > > >> > > > > > > > > Catalog services like Unity Catalog, Gravitino, > > >> > > > > > > > > Polaris should be compatible with that, otherwise it > > might > > >> > > cause > > >> > > > > > > problem > > >> > > > > > > > > for users when they are migrating from one to > > >> > > > > > > > > another. > > >> > > > > > > > > > > >> > > > > > > > > What will Polaris Server do with this location? > > >> > > > > > > > > For generic tables, Polaris will provide credential > > >> vending > > >> > for > > >> > > > > this > > >> > > > > > > > > location in near future, I don't see we will provide > > >> > > > > > > > > anything else in short or mid term, since we still > want > > to > > >> > > > promote > > >> > > > > > > > > native support for Iceberg. > > >> > > > > > > > > Or if you have anything special in your mind that you > > >> think > > >> > we > > >> > > > > should > > >> > > > > > > > > support? > > >> > > > > > > > > > > >> > > > > > > > > If Polaris has to define it in a spec, it will be hard > > to > > >> > > change > > >> > > > in > > >> > > > > > the > > >> > > > > > > > > future. > > >> > > > > > > > > Regardless of whether it is explicitly in the spec > > >> definition > > >> > > or > > >> > > > > as a > > >> > > > > > > > > reserved property key, as long as they are explicitly > > >> > > > > > > > > documented, they will be hard to change in the future. > > >> From > > >> > > that > > >> > > > > > > > > perspective, those two approaches seem the same to me. > > >> > > > > > > > > > > >> > > > > > > > > Table location is critical information that is > required > > by > > >> > the > > >> > > > > engine > > >> > > > > > > > side > > >> > > > > > > > > to read and write the tables, which should > > >> > > > > > > > > be explicitly defined to provide better sharing across > > >> > engines. > > >> > > > For > > >> > > > > > > > > example, the delta table location is passed in the > > >> > > > > > > > > table properties with a property key either "location" > > or > > >> > > "path" > > >> > > > > > > depends > > >> > > > > > > > on > > >> > > > > > > > > how the table is created. Now, if another > > >> > > > > > > > > engine wants to read the delta table, it will need to > > >> > > understand > > >> > > > > > those > > >> > > > > > > > > keys, which are controlled by Spark today. If Spark > > >> > > > > > > > > changes them one day, all sharing will stop working. > > >> > > > > > > > > > > >> > > > > > > > > As to whether we want to put it as an explicit field > or > > a > > >> > > > reserved > > >> > > > > > > key, I > > >> > > > > > > > > think for a common field among various > > >> > > > > > > > > table formats, it makes more sense to have it as an > > >> explicit > > >> > > > field. > > >> > > > > > For > > >> > > > > > > > > properties that are specific to a particular table > > format, > > >> > > > > > > > > it is more proper to just have a reserved key. > > >> > > > > > > > > > > >> > > > > > > > > If Polaris takes control of the location, I think we > > have > > >> to > > >> > be > > >> > > > > more > > >> > > > > > > > > careful > > >> > > > > > > > > and at least try to make it future-proof. > > >> > > > > > > > > > > >> > > > > > > > > I don't think Polaris is taking control of the > location, > > >> the > > >> > > > > location > > >> > > > > > > is > > >> > > > > > > > > still controlled by the engine and users today like > > table > > >> > > names. > > >> > > > > > > > > Polaris is a Catalog service, it records the generic > > table > > >> > > > entity, > > >> > > > > > and > > >> > > > > > > > > returns the information back to the user on query. > > >> > > > > > > > > It might be able to do some validation on the location > > >> (like > > >> > > > check > > >> > > > > > > > special > > >> > > > > > > > > character), but it doesn't decide which location > > >> > > > > > > > > the table will be used. I personally don't think it > is a > > >> bad > > >> > > idea > > >> > > > > to > > >> > > > > > > let > > >> > > > > > > > > the Catalog service also take control of generating > > >> > > > > > > > > the table location, but I think that will require a > lot > > of > > >> > > work. > > >> > > > > > > > > > > >> > > > > > > > > Best Regards, > > >> > > > > > > > > Yun > > >> > > > > > > > > > > >> > > > > > > > > On Wed, May 7, 2025 at 5:22 PM Dmitri Bourlatchkov < > > >> > > > > di...@apache.org > > >> > > > > > > > > >> > > > > > > > > wrote: > > >> > > > > > > > > > > >> > > > > > > > > > No worries about the name. It is a possible > > alternative > > >> > > > spelling > > >> > > > > :) > > >> > > > > > > > > > > > >> > > > > > > > > > On Wed, May 7, 2025 at 8:04 PM yun zou < > > >> > > > > yunzou.colost...@gmail.com > > >> > > > > > > > > >> > > > > > > > > wrote: > > >> > > > > > > > > > > > >> > > > > > > > > > > Hi Dmitri, > > >> > > > > > > > > > > > > >> > > > > > > > > > > Sorry, I accidentally typed your name wrong in the > > >> > previous > > >> > > > > > reply! > > >> > > > > > > > > > > Apologize for this! > > >> > > > > > > > > > > > > >> > > > > > > > > > > For the S3 issue, I think we will need to deal > with > > >> those > > >> > > > > > > regardless, > > >> > > > > > > > > > > especially with the federation work going on, we > > will > > >> > need > > >> > > to > > >> > > > > > > handle > > >> > > > > > > > > all > > >> > > > > > > > > > > those entities eventually coming from different > > >> Catalogs, > > >> > > and > > >> > > > > the > > >> > > > > > > URI > > >> > > > > > > > > > > format seems the standard format used by various > > >> Catalog > > >> > > > > > services. > > >> > > > > > > > > > > > > >> > > > > > > > > > > Best Regards, > > >> > > > > > > > > > > Yun > > >> > > > > > > > > > > > > >> > > > > > > > > > > On Wed, May 7, 2025 at 4:55 PM yun zou < > > >> > > > > > yunzou.colost...@gmail.com > > >> > > > > > > > > > >> > > > > > > > > > wrote: > > >> > > > > > > > > > > > > >> > > > > > > > > > > > Hi Dimitri and Eric, > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > Thanks a lot for the feedback! > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > For the questions: > > >> > > > > > > > > > > > - Is one value or many? > > >> > > > > > > > > > > > It will be one value, similar to the location in > > >> > Iceberg > > >> > > > and > > >> > > > > > the > > >> > > > > > > > > > > > storage_location in unity catalog. > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > Regarding to the point about having new data in > > new > > >> > > > locations > > >> > > > > > and > > >> > > > > > > > > > keeping > > >> > > > > > > > > > > > old data in old locations, do we support that > for > > >> > Iceberg > > >> > > > > > > > > > > > today? > > >> > > > > > > > > > > > For most of the Spark tables, it seems to only > > have > > >> one > > >> > > > > > location. > > >> > > > > > > > > > Also, I > > >> > > > > > > > > > > > think it is better to start restricted first, > and > > >> then > > >> > > > extend > > >> > > > > > it > > >> > > > > > > to > > >> > > > > > > > > > > > allow multiple locations when the use case > raises. > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > Ref: > > >> > > > > > > > > > > > Iceberg location: > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > > >> > > > > > > > > > > > >> > > > > > > > > > > >> > > > > > > > > > >> > > > > > > > > >> > > > > > > > >> > > > > > > >> > > > > > >> > > > > >> > > > >> > > > https://github.com/apache/iceberg/blob/main/open-api/rest-catalog-open-api.yaml#L3451 > > >> > > > > > > > > > > > Storage location in Unity Catalog: > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > > >> > > > > > > > > > > > >> > > > > > > > > > > >> > > > > > > > > > >> > > > > > > > > >> > > > > > > > >> > > > > > > >> > > > > > >> > > > > >> > > > >> > > > https://github.com/apache/iceberg/blob/main/open-api/rest-catalog-open-api.yaml#L3451 > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > - Is it a URI? > > >> > > > > > > > > > > > Yes, it will be a URI, which seems the standard > > >> catalog > > >> > > > > > > > > implementation. > > >> > > > > > > > > > > > Regarding to the point about s3 v2 s3a, i assume > > >> that > > >> > is > > >> > > a > > >> > > > > > common > > >> > > > > > > > > > > > problem that every catalog implementation needs > to > > >> > > address, > > >> > > > > and > > >> > > > > > > we > > >> > > > > > > > > will > > >> > > > > > > > > > > > stay the same on this part. At least from the > load > > >> > table > > >> > > > > point > > >> > > > > > of > > >> > > > > > > > > view, > > >> > > > > > > > > > > > Spark engine knows how to deal with such cases. > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > - Does it point to any particular file? > > >> > > > > > > > > > > > No, it doesn't point to a particular file. It is > > the > > >> > base > > >> > > > > table > > >> > > > > > > > > > location. > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > - Is it a common prefix of all files within a > > table? > > >> > > > > > > > > > > > It is supposed to be the base table location, > > which > > >> > > > > > theoretically > > >> > > > > > > > > > should > > >> > > > > > > > > > > > be the common prefix of all files within a > table I > > >> > > believe. > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > - What happens when a value does not match these > > >> > > > > expectations? > > >> > > > > > > > > > > > Whether it is one value or many is restricted by > > the > > >> > spec > > >> > > > > > > already. > > >> > > > > > > > > > > > For URI format, I think we can do a format > check, > > >> and > > >> > > fail > > >> > > > > it. > > >> > > > > > > > > > > > Other than that, we will not do any other > special > > >> > check, > > >> > > > and > > >> > > > > we > > >> > > > > > > > rely > > >> > > > > > > > > on > > >> > > > > > > > > > > > the client to put the correct value, otherwise, > > the > > >> > other > > >> > > > > > engine > > >> > > > > > > > will > > >> > > > > > > > > > > > not be able to successfully read the table. > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > For the location keyword, as Eric has pointed > out, > > >> we > > >> > can > > >> > > > > > > > potentially > > >> > > > > > > > > > > have > > >> > > > > > > > > > > > a reserved key for the properties. However, > > location > > >> > is a > > >> > > > > > common > > >> > > > > > > > > > > > enough key among various table formats, which > > >> worths a > > >> > > > > > dedicated > > >> > > > > > > > key > > >> > > > > > > > > to > > >> > > > > > > > > > > > help store and load the information in a more > > >> > > > straightforward > > >> > > > > > > > > > > > way. For things that are specific to one or two > > >> > > formats, I > > >> > > > > > think > > >> > > > > > > > it > > >> > > > > > > > > > > makes > > >> > > > > > > > > > > > more sense to use a reserved property key. > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > As a reference, in Iceberg, the CreateTable > > request > > >> and > > >> > > > > > > > TableMetadata > > >> > > > > > > > > > > does > > >> > > > > > > > > > > > have an explicit location key in the spec. For > > >> > > > > write.data.path > > >> > > > > > > > > > > > and write.metadata.path, they are passed as > > >> properties > > >> > > > today. > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > Best Regards, > > >> > > > > > > > > > > > Yun > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > On Wed, May 7, 2025 at 3:54 PM Dmitri > > Bourlatchkov < > > >> > > > > > > > di...@apache.org > > >> > > > > > > > > > > > >> > > > > > > > > > > > wrote: > > >> > > > > > > > > > > > > > >> > > > > > > > > > > >> Another point: I'm pretty sure sooner or later > > >> users > > >> > > will > > >> > > > > want > > >> > > > > > > to > > >> > > > > > > > > move > > >> > > > > > > > > > > >> their data to some other location. As an option > > >> users > > >> > > may > > >> > > > > want > > >> > > > > > > to > > >> > > > > > > > > > write > > >> > > > > > > > > > > >> new > > >> > > > > > > > > > > >> files into another location but keep old files > in > > >> > place. > > >> > > > > > > > > > > >> > > >> > > > > > > > > > > >> Also: if the location is a URI, how do we deal > > >> with s3 > > >> > > vs. > > >> > > > > s3a > > >> > > > > > > for > > >> > > > > > > > > > > >> example? > > >> > > > > > > > > > > >> > > >> > > > > > > > > > > >> In Iceberg it is quite common for different > > >> engines to > > >> > > use > > >> > > > > > > > different > > >> > > > > > > > > > > >> access > > >> > > > > > > > > > > >> tools, which often leads to different URI > > schemes. > > >> > > > > > > > > > > >> > > >> > > > > > > > > > > >> Cheers, > > >> > > > > > > > > > > >> Dmitri. > > >> > > > > > > > > > > >> > > >> > > > > > > > > > > >> On Wed, May 7, 2025 at 6:46 PM Eric Maynard < > > >> > > > > > > > > eric.w.mayn...@gmail.com > > >> > > > > > > > > > > > > >> > > > > > > > > > > >> wrote: > > >> > > > > > > > > > > >> > > >> > > > > > > > > > > >> > All good questions Dmitri — I’m especially > > >> > interested > > >> > > in > > >> > > > > the > > >> > > > > > > > first > > >> > > > > > > > > > one > > >> > > > > > > > > > > >> as > > >> > > > > > > > > > > >> > from what I understand Iceberg tables can > have > > >> > > metadata > > >> > > > > and > > >> > > > > > > data > > >> > > > > > > > > at > > >> > > > > > > > > > > two > > >> > > > > > > > > > > >> > different paths that we need to vend > > credentials > > >> > for. > > >> > > > > > > > > > > >> > > > >> > > > > > > > > > > >> > For iceberg tables, we just use special > > >> properties > > >> > to > > >> > > > > track > > >> > > > > > > > these > > >> > > > > > > > > > > >> > locations. I wonder if we couldn’t do the > same > > >> for > > >> > > > generic > > >> > > > > > > > tables. > > >> > > > > > > > > > > >> > > > >> > > > > > > > > > > >> > On Wed, May 7, 2025 at 3:42 PM Dmitri > > >> Bourlatchkov < > > >> > > > > > > > > > di...@apache.org> > > >> > > > > > > > > > > >> > wrote: > > >> > > > > > > > > > > >> > > > >> > > > > > > > > > > >> > > Hi Yun, > > >> > > > > > > > > > > >> > > > > >> > > > > > > > > > > >> > > Please clarify the meaning of the value of > > the > > >> new > > >> > > > > > location > > >> > > > > > > > > > > attribute. > > >> > > > > > > > > > > >> > > > > >> > > > > > > > > > > >> > > - Is is one value or many? > > >> > > > > > > > > > > >> > > - Is it a URI? > > >> > > > > > > > > > > >> > > - Does it point to any particular file? > > >> > > > > > > > > > > >> > > - Is it a common prefix of all files > within a > > >> > table? > > >> > > > > > > > > > > >> > > - What happens when a value does not match > > >> these > > >> > > > > > > expectation? > > >> > > > > > > > > > > >> > > > > >> > > > > > > > > > > >> > > Thanks, > > >> > > > > > > > > > > >> > > Dmitri. > > >> > > > > > > > > > > >> > > > > >> > > > > > > > > > > >> > > On 2025/05/07 21:50:19 yun zou wrote: > > >> > > > > > > > > > > >> > > > Hi folks, > > >> > > > > > > > > > > >> > > > > > >> > > > > > > > > > > >> > > > I would like to propose to add an > optional > > >> > > > `location` > > >> > > > > > > field > > >> > > > > > > > to > > >> > > > > > > > > > > >> > > > CreateGenricTable Request and > > >> LoadGenericTable > > >> > > > > response. > > >> > > > > > > > > > > >> > > > > > >> > > > > > > > > > > >> > > > The `location` is the location for the > > table, > > >> > > which > > >> > > > is > > >> > > > > > > > common > > >> > > > > > > > > to > > >> > > > > > > > > > > >> most > > >> > > > > > > > > > > >> > > table > > >> > > > > > > > > > > >> > > > formats including Iceberg, Delta, Hudi, > > csv, > > >> > > parquet > > >> > > > > > etc. > > >> > > > > > > > The > > >> > > > > > > > > > > >> location > > >> > > > > > > > > > > >> > > > information is critical for loading the > > >> table at > > >> > > > > engine > > >> > > > > > > > side, > > >> > > > > > > > > > > >> having a > > >> > > > > > > > > > > >> > > > dedicated keyword could help improve the > > >> > > robustness > > >> > > > > for > > >> > > > > > > > cross > > >> > > > > > > > > > > engine > > >> > > > > > > > > > > >> > > > sharing, instead of relying on the > > properties > > >> > > passed > > >> > > > > by > > >> > > > > > > the > > >> > > > > > > > > > client > > >> > > > > > > > > > > >> > side. > > >> > > > > > > > > > > >> > > > > > >> > > > > > > > > > > >> > > > Furthermore, this information is also > > >> required > > >> > to > > >> > > > > > provide > > >> > > > > > > > > > > credential > > >> > > > > > > > > > > >> > > > vending capabilities later. > > >> > > > > > > > > > > >> > > > > > >> > > > > > > > > > > >> > > > Here is the PR for adding the spec: > > >> > > > > > > > > > > >> > > > > > https://github.com/apache/polaris/pull/1543 > > >> > > > > > > > > > > >> > > > > > >> > > > > > > > > > > >> > > > Looking forward to your reply and > feedback! > > >> > > > > > > > > > > >> > > > > > >> > > > > > > > > > > >> > > > Best Regards, > > >> > > > > > > > > > > >> > > > Yun > > >> > > > > > > > > > > >> > > > > > >> > > > > > > > > > > >> > > > > >> > > > > > > > > > > >> > > > >> > > > > > > > > > > >> > > >> > > > > > > > > > > > > > >> > > > > > > > > > > > > >> > > > > > > > > > > > >> > > > > > > > > > > >> > > > > > > > > > >> > > > > > > > > >> > > > > > > > >> > > > > > > >> > > > > > >> > > > > >> > > > >> > > > > > >
