Meeting minutes
<ora> My intro slides are here: https://
<pfps> What's the meeting passcode?
<pfps> thanks
<TallTed> bleah. complete conflict with DID WG...
<AndyS> No objection
ora: We can record this if there are no objections
… ok we can record this
RDF-Star: 2 Years Status
Ora: Everyone introduced each other.
Slideset: https://
Ora: Talking about RDF history (see slides)
Ora: talking about Statements about statements
Ora: talking about use cases
Ora: talking about Challenges
<TallTed> ora / ktk - please share the link to the recording as soon as it's known.
Ora: talking about Semantics
Ora: talking about Syntax
Ora: talking about Status
<niklasl> My slides are at: https://
Slideset: https://
niklasl: Presenting Reifiers
niklasl: talking about a simple triple
… talking about triple terms
niklasl: talking about triple terms are abstract
niklasl: talking about reifier syntax
… talking about reifier suguar & reifier and assertion
niklasl: talking about annotation sugar
niklasl: talking about naming reifiers
niklasl: talking about kinds of reifiers
niklasl: talking about provenance
niklasl: talking about qualification
niklasl: talking about compound qualification
niklasl: talking about compound provenance
niklasl: talking about varying granularity
niklasl: talking about name forms
niklasl: talking about historical circumstances
niklasl: finishing presentation.
pchampin: is the wikidata example made up?
niklasl: it's almost like this
<pfps> Wikidata has an annotation mechanism that generalizes the one in labelled property graphs, and is quite different from how things are done in RDF.
ktk: do we have syntax that is asserted by default
niklasl: yes the annotation syntax, in turtle
pfps: in wikidata it's hard to map it to RDF, as you can see. it's closer to labeled PGs
ora: we can discuss what we want to discuss in the remaining time available at TPAC
niklasl: I have another presentation for in-depth discussions
ora: we decided to switch to a backlog-based model from now on. we have some dicussions tagged for F2F discussions here
tl: I have another topic for Thursday, slides not ready yet
Un-star operation to support RDF Dataset Canonicalization?
gkellogg: we talk about "un-star" since long time
… we want to transform the representation in some form of other representation
… I assumed this will be standard reification.
… is the mechanism by which we transform triple terms simply reification triples?
… should we use different types and properties for reification triples?
<bengo> w3c/
<gb> Issue 114 Un-star operation to support RDF Dataset Canonicalization? (by niklasl) [needs discussion] [discuss-f2f]
pchampin: from the CWG: we defined RDF-Star semantics on top of the standard RDF semantics
… we are using the same term "un-star" for a totally different purpose now
… many people asked why do you not just singleton named graphs.
… I inteded to write something and share it in advance but didn't manage to.
… do we want to have the "un-star" mapping to be lossless?
… I have a simpler version but it's not 100% lossless
<Zakim> gkellogg, you wanted to discuss conflation with reifiers and graph names
gkellogg: the issue is that we might create something that inserts triple in an existing named graph
pchampin: using reifiers as graph names would definitely create a number of issues. I would rather go for encoding each triple term into a blanknode made singleton named graph
… we encode the triple term into a singleton named graph that is a blank node
… we also add another graph that says "this blank node is a triple term"
… and any other blank node that is a triple term.
pchampin: I try to keep the un-star mapping as liberal as possible.
… if there is no triple term in an existing dataset this should work. but if you have already an un-star set in it, it becomes an edge-case
… with that we could convert every RDF-Star 1.2 into RDF 1.1 "classic"
<Zakim> AndyS, you wanted to ask about scope of the solution
AndyS: we might want to convert an RDF 1.1 graph with reification into a RDF 1.2 graph.
… what pchampin talked about, it got complicated once you said you want to put a dataset into a dataset that already contains a graph that has reification
… we might simplify that by saing it's two datasets and it becomes a merge operation
gtw: we should do that per triple-term. it's natural thing to look at what that looks like per reifier.
tl: Dydra already implements RDF-Star with named graphs. there is some experience
… they are happy to share the experience.
… The mapping to standard triples with the RDF reification vocab would be useful too and I would like to have it lossless
<Zakim> bengo, you wanted to ask if unstar to graph and unstar to dataset are both useful to standardize for different reasons
bengo: it would be useful to un-star to triples or graphs for different reasons.
pchampin: to respond to AndyS about staring standard reification: that is for me a totally different problem, it was not my intention in that proposal
… I had two goals: Canonicalization & flattening
gkellogg: regarding the notion to create named graphs per reifiers.
… querying would become much more difficult.
niklasl: it's important to un-star to RDF "classic" for a number of reasons
… for example to be able to add it to an existing graph store as soon as possible
… the problem is union graphs that many stores do.
… I believe using classic reification properties is frugal.
tl: we had an experiment with nested named graphs. the problem is that we have to extend SPARQL to query that. triple terms are much more powerful in that respect.
… it wouldn't be that easy with just named graphs. and also other reasons. things get tricky on SPARQL level
ACTION: pchampin to write a PR on rdf-concepts for the unstar mapping
<gb> Created action #129
ora: the question is how much effort do we want to put into edge cases that might not occur anyway
pchampin: I will write a pull-request with some examples
ora: this will go back into the backlog
pchampin: let's scan the backlog to prepare for Thursday as well
ora: good idea
Backlog to add additional issues
backlog: https://
<pchampin> https://
pchampin: these are the ones "needs discussion"
pchampin: we talk about w3c/
<gb> Issue 79 Reconsider bidirectional (bidi) tag? (by termontwouter) [needs discussion] [wr:open]
<gkellogg> PROPOSAL: The working group has considered w3c/
<pchampin> +1
<gkellogg> +1
<ora> +1
<AndyS> +1
<gtw> +1
<Dominik_T> +1
<doerthe> +1
<ktk> +1
<niklasl> +1
<tl> +1
<Tpt> +1
RESOLUTION: The working group has considered w3c/
<gb> Issue 79 Reconsider bidirectional (bidi) tag? (by termontwouter) [needs discussion] [wr:open]
<tl> AndyS thanks!
<TallTed> Does anyone have the URL to the recording?
<TallTed> pchampin - Note that the minutes at <https://
<TallTed> pchampin -- bah, I'm looking at rdf-star for did logs. sorry.
TallTed: not sure who started the recording, probably pchampin or ora
niklasl: great slides by the way
<AndyS> +1
<niklasl> Thank you! I had a lot of great feedback from the group, so I won't take all the credit. :)
<gkellogg> Power out in the hotel, so there will be some delay before we start up.
<TallTed> i|I will not start a new log at midnight|previous meeting: https://
<TallTed> i|I will not start a new log at midnight|next meeting: https://
<TallTed> i|I will not start a new log at midnight|agenda: https://
<TallTed> i/I will not start a new log at midnight/previous meeting: https://
<TallTed> i/I will not start a new log at midnight/next meeting: https://
<TallTed> i/I will not start a new log at midnight/agenda: https://
<pchampin> just so you know, there is a power outage in the TPAC hotel, so the meetings are disrupted
<dlehn> 9 of us are on zoom and starting to chat anyway. we're not sure what that agenda should be.
<anatoly-scherbakov> gtfierro/
<anatoly-scherbakov> pbonte/
<gkellogg_> Power out may go on until 3:00 PDT, or about 3 1/2 hours from now.
gkellogg_: oh wow what should we do?
<gkellogg_> There's really nothing we can do and we should end the meetings for the day. We may start something up when power is back, but that's probably too late for people in Europe.