W3C

– DRAFT –
RDF-Star Working Group Weekly Meeting

06 July 2023

Attendees

Present
AndyS, gtw, ktk, pchampin, rubensworks, TallTed, Tpt
Regrets
AZimmermann, DArndt, DominikT, EFranconi, gkellogg, OHartig, OLassila, PPatel-Schneider
Chair
ktk
Scribe
pchampin, rubensworks

Meeting minutes

Scribe: Alexiev, Vladimir (alternate: Taelman, Ruben)

Approval of last week's minutes: 1

ktk: Any comments on last week's minutes?

pchampin: I discovered that I closed the conversation when I left last week.
… There is also a wrong GH link. Only the link by the scribe-bot is wrong.

ktk: Should we use the full links instead?

https://www.w3.org/2023/06/29-rdf-star-minutes.html#x212

TallTed: Is there a correct link near the wrong one?

pchampin: The scribe script link is wrong, and I can fix that. The other bot's one seems to be wrong as well, and Gregg put in the correct link. I can fix this mess.

<ktk> PROPOSAL: Approve last week's minutes

<ktk> +1

+1

<TallTed> +1 upon PAC's fix

<gtw> +1

+1

<AndyS> +1

RESOLUTION: Approve last week's minutes

<TallTed> ack

Querying nested quoted triples at an unknown depth 2

w3c/sparql-query#96

rubensworks: in SPARQL-star, it is possible to have top-down access to quoted triples
… do we want to allow bottom-up access to quoted triples, to be able to query quoted triples of unknown depth?
… This is not about adding specific syntactical support to SPARQL,
… more about asking to the group: do we need this? do we want to somehow support it?

AndyS: the problem might be more complex than what's in the issue (which uses the same predicate at all depths)
… you might also want to match not down to the end.

rubensworks: agree with first point: my first proposal is inspired by property paths,
… but further down in the issue, I describe a more genetic possible solution (QUOTED keyword),
… where you don't necessarily to specify the path to the quoted triple

TallTed: I like the initial concept of this being an extension of property paths;
… feels more intuitive to me than the analogy with GRAPH.
… But it is a deep issue, requiring significant math-heads.
… (aside: it is a shame that some people from early RDF are not part of this group)

ktk: [question about the proposal in the issue]

TallTed: there is a strong wish in the community to get all the intermediaries of property paths
… There was a proposal in the early proposal of property paths, to specify an arbitrary depth,
… it is implemented in Virtuoso, but I don't know what happened to it in the spec.

AndyS: does the charter allows us to make this kind of change?
… not an errata, definitely a new feature, requires to change the SPARQL data model.

<Souri> I had presented a paper at the KGC 2022 conference related to this and it is being, in principle, discussed for inclusion in the SQL/PGQ standard's next version: https://zenodo.org/record/6511401

AndyS: Is it possible? yes. But in scope?....
… If we take on this feature, other features will be required as well.
… The reason it was rejected was a formal objection from some university, it adds much complexity.

AndyS: [disussion about living standard, that needs to reflect the position of the wider community]

ktk: any of the implementers on the call want to comment?

Souri: I call this neighbourhood-aware path, see link to paper above
… this was not included in PGQ because of complexity issue, but is much discussed at the moment
… there is a big need for this, and SPARQL property paths is simple and does not provide this
… it would be nice to have it, if time allows

<TallTed> Is there a link to any SQL/PGQ documentation? I know it will be put behind a paywall when finalized, but maybe there's a draft available?

Souri: I work with veteran standard people in SQL and PG, they acknowledge that it is a really nice to have

Tpt: I agree this is something we want to think about, but that's complex.
… Should probably not be a priority at this point, and consider it later if we have time.

<AndyS> https://www.w3.org/groups/cg/sparql-dev/

rubensworks: implementation-wise, we experimented with a number of indexing approaches,
… the second proposal in the issue (QUOTED keyword) is easy to support in an index,
… as an extension to existing triple stores.

TallTed: could Souri please share a link to this work on PGQ?

gtw: concur with what has been said: should not be a priority and probably out of scope;
… but happy to see experiments on this in the SPARQL-dev CG.

pchampin: Wondering if we have a label for future work?

<TallTed> `deferred` is common

ktk: I propose everyone to write down what Greggory said in the issue, and link to it in sparql-dev.

<pchampin> the label "ms:futurework" looks like a good match

AndyS: Ruben, will you write this down in sparql-dev?

rubensworks: yes.

<AndyS> Issues at w3c/sparql-dev

ktk: Ruben will post the issue.

Review of open actions, available at 3

pchampin: The renaming to sparql-dev has been done. The old URLs of the CG and GH repo redirect.
… The public mailinglist already existed, so we created public-sparql-dev-cg instead.

AndyS: The other one is where all Cfps go.

pchampin: And other spam.

ktk: Remaining work is to update all text.

pchampin: We did some renaming already.

pchampin: Remaining issues are long-standing issues still to be solved.

Review of pull requests, available at 4

pchampin: We decided to shift the mobile PR from making it mobile-friendly, to just fixing his concrete problems. So I think we can close this PR, but let's wait for Dominik to be present.

ktk: He said would provide screenshots.

AndyS: What about the problem with echidna in sparql-update

https://github.com/w3c/sparql-query/actions/runs/5477182667/jobs/9975831813#step:3:575

pchampin: There is probably a validation issue.

pchampin: Pointy brackets around an URL.

pchampin: I noticed last week a credentials issue, but it seems to be resolved.

AndyS: It's intermittent.

Any Other Business (AOB), time permitting

ktk: Next week I'm not here.

AndyS: How many people will go to TPAC in person?

ktk: I booked a hotel; yes.

<pchampin> I will be present in person

ktk: Ora is confident he will go.

<TallTed> sadly, insufficient travel budget

AndyS: Gregg might not be able to.

<Souri> Where is the TPAC being held? When?

ktk: Not cheap for those coming from the US.

https://www.w3.org/2023/09/TPAC/

AndyS: It will be hybrid.
… Our slot is on Tuesday.

https://www.w3.org/events/meetings/6b4775ff-57d7-497a-a36e-c5f2a2810723/

<Souri> Which helps because that way I don't miss any meetings here! :-)

<ktk> rubensworks: thanks for scribing!

<AndyS> pchampin? Got a minute?

<AndyS> I'm not seeing an error locall (well, I use the usual 1E/1W about included documents)

<AndyS> Ack

<AndyS> Where?

<pchampin> s/<pchampin> +1/<pchampin> <pchampin> +1/

Summary of resolutions

  1. Approve last week's minutes
Minutes manually created (not a transcript), formatted by scribe.perl version 210 (Wed Jan 11 19:21:32 2023 UTC).

Diagnostics

Succeeded: s/Scribe rubensworks//

Succeeded: s/2202/2022/

Succeeded: s|SPARQL-dev-cg|https://www.w3.org/groups/cg/sparql-dev/|

Succeeded: s/in an index./in an index,

Succeeded: s/AndyS/ktk/

Failed: s/<pchampin> +1/<pchampin> <pchampin> +1/

Succeeded: s/the label "ms:futurework" looks like a good match/<pchampin> the label "ms:futurework" looks like a good match

Succeeded: s/I will be present in person/<pchampin> I will be present in person

No scribenick or scribe found. Guessed: pchampin

Maybe present: Souri

All speakers: AndyS, gtw, ktk, pchampin, rubensworks, Souri, TallTed, Tpt

Active on IRC: AndyS, gtw, ktk, pchampin, rubensworks, Souri, TallTed, Tpt