IRC log of dawg on 2005-10-04

Timestamps are in UTC.

14:28:41 [RRSAgent]

RRSAgent has joined #dawg

14:28:41 [RRSAgent]

logging to http://www.w3.org/2005/10/04-dawg-irc

14:29:14 [DanC]

RRSAgent, stop

14:30:35 [Zakim]

+??P21

14:30:38 [AndyS]

zakim, ??P21 is AndyS

14:30:38 [Zakim]

+AndyS; got it

14:30:42 [Zakim]

+DanC

14:31:24 [DanC]

DanC has changed the topic to: RDF Data Access http://www.w3.org/2001/sw/DataAccess/ 4 Oct. scribe: AndyS

14:31:30 [DanC]

Zakim, take up item 1

14:31:30 [Zakim]

agendum 1. "Convene, take roll, review records and agenda" taken up [from DanC]

14:31:37 [DanC]

Meeting: RDF Data Access Weekly

14:31:41 [DanC]

Scribe: AndyS

14:31:43 [DanC]

Chair: DanC

14:32:07 [JanneS]

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14:32:48 [DanC]

Regrets: SteveH, LeeF, DaveB, JosD

14:32:53 [DanC]

Regrets: SteveH, LeeF, DaveB, JosD, SouriD

14:32:58 [Zakim]

+[IPcaller]

14:33:13 [SerT]

Enrico and myself are dialing right now

14:33:18 [DanC]

Zakim, IPcaller is JanneS

14:33:18 [Zakim]

+JanneS; got it

14:33:18 [JanneS]

Zakim, IPcaller is JanneS

14:33:19 [Zakim]

sorry, JanneS, I do not recognize a party named 'IPcaller'

14:33:39 [Zakim]

+Enrico_Franconi

14:34:25 [DanC]

Regrets: SteveH, LeeF, DaveB, JosD, SouriD, PatH

14:34:44 [AndyS]

Regrets: EricP

14:35:00 [patH]

But PatH is lurking on IRC.

14:35:12 [DanC]

hi

14:35:15 [AndyS]

Regrets: Kendall

14:35:25 [DanC]

Regrets: SteveH, LeeF, DaveB, JosD, SouriD, PatH, KendallC

14:36:17 [DanC]

Zakim, who's talking?

14:36:28 [Zakim]

DanC, listening for 10 seconds I heard sound from the following: JanneS (79%), Enrico_Franconi (9%), DanC (74%)

14:36:36 [DanC]

Zakim, mute JanneS

14:36:36 [Zakim]

JanneS should now be muted

14:36:59 [Zakim]

+[UMD]

14:37:21 [DanC]

Zakim, who's on the phone?

14:37:21 [Zakim]

On the phone I see AndyS, DanC, JanneS (muted), Enrico_Franconi, [UMD]

14:37:23 [bijan]

bijan has joined #dawg

14:37:29 [AndyS]

zakim, UMD has Bijan

14:37:29 [Zakim]

+Bijan; got it

14:37:30 [DanC]

Regrets: SteveH, LeeF, DaveB, JosD, SouriD, PatH, KendallC, EricP

14:38:25 [JanneS]

I've got headset on now - echo should have gone.

14:38:28 [JanneS]

Zakim, unmute JanneS

14:38:28 [Zakim]

JanneS should no longer be muted

14:38:48 [bijan]

Zakim, who's here?

14:38:48 [Zakim]

On the phone I see AndyS, DanC, JanneS, Enrico_Franconi, [UMD]

14:38:49 [Zakim]

[UMD] has Bijan

14:38:51 [Zakim]

On IRC I see bijan, JanneS, RRSAgent, Zakim, franconi, SerT, patH, AndyS, afs, ericP, DanC

14:38:59 [DanC]

Agenda: http://lists.w3.org/Archives/Public/public-rdf-dawg/2005OctDec/att-0001/_ag4Oct.html

14:39:12 [DanC]

agenda + DAWG schedule

14:40:26 [DanC]

agenda order = 1, 6, 12

14:40:34 [DanC]

agenda order=1, 6, 12

14:40:39 [DanC]

Zakim, agenda order=1, 6, 12

14:40:39 [Zakim]

I don't understand 'agenda order=1, 6, 12', DanC

14:40:43 [DanC]

Zakim, agenda order is 1, 6, 12

14:40:43 [Zakim]

ok, DanC

14:41:14 [DanC]

scribe for Oct 11?

14:41:39 [DanC]

Janne offers for 18 Oct

14:41:50 [DanC]

ACTION: EricP to arrange for 200 response from http://www.w3.org/2005/08/sparql-protocol-query [DONE]

14:41:58 [DanC]

ACTION: KC to revert query-request from xs:all back to xs:seq and note this is due to limiations of XML Schema. [DONE]

14:42:13 [DanC]

next meeting is tentatively scheduled for 11 Oct, contingent on recruiting a scribe

14:42:21 [DanC]

Zakim, next agendum

14:42:21 [Zakim]

agendum 6. "issues#rdfSemantics, issues#owlDisjunction" taken up [from DanC]

14:43:04 [Zakim]

+EliasT

14:43:22 [AndyS]

From PatH summary email

14:44:24 [AndyS]

.. Sergio has summary of change areas

14:44:57 [EliasT]

EliasT has joined #dawg

14:45:16 [EliasT]

Zakim, who's on the phone

14:45:16 [Zakim]

I don't understand 'who's on the phone', EliasT

14:45:22 [DanC]

Zakim, who's on the phone?

14:45:22 [Zakim]

On the phone I see AndyS, DanC, JanneS, Enrico_Franconi, [UMD], EliasT

14:45:23 [Zakim]

[UMD] has Bijan

14:45:55 [AndyS]

Enrico: entailment 1/ def of pattern solution : no Bnodes

14:46:07 [DanC]

-> http://www.w3.org/2001/sw/DataAccess/rq23/#PatternSolutions 2.4 Pattern Solutions

14:46:11 [AndyS]

.. 2/ patten matching include entailment

14:46:22 [bijan]

DanC: http://www.mindswap.org/~bparsia/rdfssemsparql.txt

14:46:30 [bijan]

(not perm)

14:46:32 [bijan]

er.

14:46:33 [AndyS]

Add skolemised and unskolemisation

14:46:34 [bijan]

DanC, http://www.mindswap.org/~bparsia/rdfssemsparql.txt

14:46:41 [EliasT]

Zakim, mute me

14:46:41 [Zakim]

EliasT should now be muted

14:47:12 [AndyS]

Enrico: skolemization found not to work

14:47:21 [DanC]

er... my browser doesn't wrap rdfssemsparql.txt very well

14:47:22 [AndyS]

(Proof?)

14:47:37 [SerT]

skolemization does work

14:47:46 [AndyS]

optional in UNION and SELECT for minimization

14:47:54 [bijan]

It's just text.../me tried ot move fast

14:49:02 [AndyS]

No bnodes in data =>none in results

14:49:55 [patH]

if I follow that, I disagree. Bnode in answer can be bound to a query var in query.

14:49:56 [AndyS]

Syntactic bnodes in dataset => skolemize to constants => remember process => entail => deskolemize with mapping

14:50:22 [AndyS]

(Don't understand why Pat's approach was found wrong)

14:50:31 [patH]

Whoops, sorry, withdraw previous comment.

14:51:36 [patH]

Pat doesnt follow why Pat is wrong, either.

14:51:49 [AndyS]

q+ to ask whether this mapping undone after base pattern or after query

14:53:01 [AndyS]

Enrico: may be a problem with revealing bnodes labels

14:53:19 [AndyS]

.. use case (Ron's ?- ed) not met in this case

14:53:22 [bijan]

DanC, http://www.mindswap.org/~bparsia/rdfssemsparql.html

14:53:39 [bijan]

I don't think you are wrong.

14:53:41 [bijan]

pat

14:56:15 [AndyS]

.. preservation of told bnodes

14:56:39 [AndyS]

.. on abstract syntax, not lean graph

14:58:07 [AndyS]

q+ to ask about named graphs

14:58:23 [Zakim]

+SteveH

14:58:37 [AndyS]

Bijan: lean store = abstract syntax+entailment queries

14:59:26 [SteveH]

SteveH has joined #dawg

14:59:33 [AndyS]

How to specify the query mode: protocol, query flags, (per graph? per base pattern?)

15:00:03 [AndyS]

Per endpoint? Or on a per request basis (server can reject

15:00:32 [AndyS]

No proposal to change the QL at the moment

15:00:59 [SteveH]

zakim, mute me

15:00:59 [Zakim]

SteveH should now be muted

15:01:01 [AndyS]

Default is per service and include in description (scribe checking)

15:01:46 [AndyS]

New "entailment" -> "abstract syntax", "told bnode"

15:02:24 [patH]

It is impossible to follow this from the IRC record. Just a remark.

15:02:48 [AndyS]

DanC: suggest: say "redundant answers are OK"

15:03:40 [patH]

+1

15:04:10 [AndyS]

Enrico: only told bNode redundance ?

15:05:31 [patH]

Suggest not qualifying this, since removing redundacy is potentially high cost for service agent, independent of entailment issues.

15:07:41 [AndyS]

DanC: concern about introducing a new entailment

15:08:01 [AndyS]

.. alt: one kind of service - may get redundancies

15:08:33 [AndyS]

Bijan: service advertises abilities (a property of the service - single valued)

15:09:41 [AndyS]

(My server does it based on graph queried - not just service)

15:10:51 [AndyS]

DanC: Tension between abs syntax and servers that wish to forget it

15:11:03 [AndyS]

Bijan: has examples of both

15:11:18 [AndyS]

DanC: clients loose

15:11:39 [AndyS]

May be possible to have a server that only has lean graphs

15:12:12 [AndyS]

(Does cwm lean graphs?)

15:13:03 [DanC]

(yes)

15:13:11 [DanC]

(at least in some cases, I gather)

15:13:32 [AndyS]

When? During log:semantics?

15:13:35 [DanC]

I'm not sure

15:14:06 [DanC]

DanC: suppose we just say: clients lose; we don't require servers to support querying abstract syntax

15:14:14 [patH]

BUt imagine a RSS-feed type query service, required to be lean might be impossibly expensive and not important in use.

15:14:25 [bijan]

DanC, is an aspect or presumption of your position that we shouldn't specify answers for sparql against graphs under, e.g., rdfs semantics?

15:14:57 [DanC]

quite. I'm sticking to the idea that rdfs semantics is done by closure before query

15:15:02 [patH]

I'd be happy with that.

15:15:22 [bijan]

Oh. We're at completely different points

15:16:02 [patH]

Guys, consider that the RDFS case can be implemented in various ways even if spec describes result in terms of closure or in terms of inference.

15:16:24 [bijan]

Yes, I just want it specified

15:16:35 [bijan]

And in the protocol I want us to identify names for these modes (extensible)

15:16:40 [bijan]

Etc.

15:17:10 [patH]

But there are theorems showing rdfs-entail = simple-entail from rdfs closure. SO why does it matter which way we describe it?

15:17:36 [franconi]

because there is no way to characterise the told-bonode semantics

15:17:41 [bijan]

It doesn't, expect insofar as it prevents extensibily to owl

15:17:53 [franconi]

yes

15:18:09 [patH]

I calim it can be done in terms of scope. Thqats orthogonal issue to the rdf/rdfs/owl?/entailment issue.

15:18:52 [patH]

Bijan, we should be honest about not providing owl entailment. We don't, so lets not pretend otherwise.

15:19:19 [franconi]

Let's not start again ont that :-)

15:19:20 [DanC]

stepping back, this telcon has already been valuable to me; I think i understand Enrico's proposal much more clearly than I did before.

15:20:03 [AndyS]

+1

15:22:37 [bijan]

patH, yes, but I think there is a clear path forward and I would like it to be a simple extension

15:22:44 [bijan]

Rather than a rewrite of some part of the spec

15:23:56 [AndyS]

Test harness

15:24:00 [patH]

Bijan, OK, but we will need to wrap this around with warnings about not expecting too much, etc.. And there is an orthogonal concern, that other, different, generalizations will be blocked in order to keep the entailments pure.

15:24:06 [AndyS]

What effect does this have on the tests?

15:24:33 [AndyS]

Bijan: impls not doing entailment

15:24:41 [AndyS]

(Andy -> no - 3Store)

15:24:52 [patH]

Bijan, I see this already in the concern for a semantic story for told bnodes. THere are clear practical use cases for this.

15:26:38 [bijan]

Yes, but I'm hearing that the test cases might be indifferent to told bnode redundancy!

15:27:03 [AndyS]

[] rdf:type rs:ResultSet ;

15:27:03 [AndyS]

rs:resultVariable "x" ;

15:27:03 [AndyS]

rs:solution [ rs:binding [ rs:value 1 ;

15:27:03 [AndyS]

rs:variable "x"

15:27:03 [AndyS]

]

15:27:04 [AndyS]

] .

15:28:01 [SteveH]

we have a count for queryies with ORDER BY

15:28:22 [SteveH]

(I'm muted, in a noisy room)

15:29:13 [AndyS]

So logical equiv data graphs lead to logical equiv result sets

15:29:49 [AndyS]

Err - no - because result set bnodes aren't redundant.

15:30:32 [patH]

Wait, we have to specify what semantics we are applying to the result sets.

15:30:55 [AndyS]

It's "logical equivance" - which may not be enough

15:30:58 [AndyS]

:-(#

15:31:23 [patH]

Is that defined anywhere for result sets?

15:31:42 [DanC]

yes, if you squint...

15:31:49 [AndyS]

Tests README

15:31:59 [Zakim]

-EliasT

15:32:51 [franconi]

patH: the semantics we gave in our document (conjunctive existential) would be the right one, I guess

15:32:58 [JanneS]

thanks for letting me catch up via just listening you today - have to go now for tonight, bye

15:33:09 [Zakim]

-JanneS

15:33:12 [JanneS]

JanneS has left #dawg

15:33:28 [patH]

Franconi, can you send the URI for that doc?

15:36:08 [DanC]

so http://www.mindswap.org/~bparsia/rdfssemsparql.html is progress on ACTION: Enrico to take a pass through the editor's draft, listing what will change with the new semantics understanding ...

15:36:35 [DanC]

it's done to my satisfaction... some discussion as to whether it's done to the satisfaction of the meeting [not to mention whether we're quorate to discharge actions anyway]

15:36:41 [bijan]

* Ditch the whole GRAPH/NAMED thing (or push it in soma appendix).

15:37:05 [franconi]

http://www.w3.org/mid/a80c7960501c216dc201b3552d81ab03@inf.unibz.it

15:37:10 [AndyS]

AndyS confused by that proposal - can it be in the algebra?

15:37:13 [patH]

Ta.

15:37:57 [DanC]

ACTION Bijan: estimate impact of "abstract syntax entilemnt" etc. on WG test harness

15:38:45 [DanC]

Bijan: ... algebra ...?

15:39:05 [DanC]

AndyS: GRAPH is just the same algebra with 4-tuples rather than 3-tuples

15:39:39 [DanC]

Enrico: yes, at that level, it's just another column in the results[?], but we don't have a semantics at the RDF level [er... he said it better]

15:40:45 [patH]

I know this is considered fighting words, but this sounds to me like the semantics police blocking a useful mechanism.

15:41:18 [DanC]

DanC: yes, months ago, [in Helsinki] I argued against SOURCE/GRAPH on the grounds that we don't really understand it formally... but now the users expect it

15:41:34 [patH]

And, more to the point, they are using it.

15:41:55 [DanC]

Bijan: so... can we put GRAPH in an appendix, or put a warning around it or something?

15:42:07 [DanC]

DanC: yes, I think that's a good idea...

15:42:09 [AndyS]

Proposal to add text to warn there are no formal semantics for GRAPH yet (or in time for rc)

15:42:11 [AndyS]

Proposal to add text to warn there are no formal semantics for GRAPH yet (or in time for rec)

15:42:13 [patH]

And, BTW, it does have a (trivial) clear semantics.

15:42:35 [patH]

Even though it might not be in a W3C spec yet :-)

15:42:52 [AndyS]

Idea: formalise during CR period

15:42:54 [DanC]

... some discussion of saying that GRAPH is at risk during CR, with a CR exit criterion that we formalize it.

15:43:14 [franconi]

patH: what are we blocking exactly? My attitude is to formaise whatever users do. So, if I forgot something, let me understand what.

15:43:26 [patH]

we already did, in the named graph paper. BUt Id wlecome discusion/criticism.

15:44:01 [patH]

franconi, maybe I was reading too mcuh intot he enigmatic IRC record. The red flag was the calim that named graphs have no semantics.

15:44:14 [AndyS]

Many users want GROUP.

15:45:16 [AndyS]

I thought Pat had at least a first cut on its formalization - Enrico - do you have comments on that (later? email?)

15:45:45 [patH]

Lets do it by email, it may take time. Certainly details :-)

15:45:48 [franconi]

Aha, I don't claim that they can not have semantics, I only claim that at the current stage of SPARQL it may take some (long) time to have it in a complete form. So, it is a matter of timing, I guess

15:46:19 [patH]

OK, then Im more optimisitc. Lets talk about this by email.

15:46:34 [franconi]

sure

15:46:37 [AndyS]

Dan -- Schedule discussion

15:46:49 [AndyS]

CR ==> ~Oct 37th

15:46:57 [AndyS]

XQuery - got comments

15:47:01 [patH]

BTW, we worked iit out for the common logic propposal in some detail. I'll send you the URI.

15:47:18 [AndyS]

q+ to ask about XSD decimals

15:47:38 [AndyS]

SWBP review - some comments

15:47:39 [patH]

Pat has to leave, his trun to present the next paper :-)

15:47:46 [AndyS]

Thx Pat

15:47:52 [bijan]

ta, pat

15:47:57 [bijan]

ta, pat's ghost

15:51:34 [AndyS]

(I would need a clearer explaination of the issue re XQuery after all this time)

15:52:31 [bijan]

Ha!

15:52:47 [AndyS]

The chair is committed to get to CR.

15:56:42 [EliasT]

10AndyS: 01CR ==> ~Oct 37th

15:57:15 [DanC]

Zakim, take up item schedule

15:57:15 [Zakim]

agendum 12. "DAWG schedule" taken up [from DanC]

16:05:26 [Zakim]

-SteveH

16:06:53 [DanC]

ADJOURN.

16:06:58 [Zakim]

-Enrico_Franconi

16:07:01 [Zakim]

-[UMD]

16:09:28 [Zakim]

-DanC

16:09:30 [Zakim]

-AndyS

16:09:31 [Zakim]

SW_DAWG()10:30AM has ended

16:09:32 [Zakim]

Attendees were AndyS, DanC, JanneS, Enrico_Franconi, Bijan, EliasT, SteveH

16:09:51 [SteveH]

SteveH has joined #dawg

16:12:55 [DanC]

RRSAgent, make logs world-access

16:31:25 [AndyS]

rrsagent, please leave

16:31:25 [RRSAgent]

I see 3 open action items saved in http://www.w3.org/2005/10/04-dawg-actions.rdf :

16:31:25 [RRSAgent]

ACTION: EricP to arrange for 200 response from http://www.w3.org/2005/08/sparql-protocol-query [DONE] [1]

16:31:25 [RRSAgent]

recorded in http://www.w3.org/2005/10/04-dawg-irc#T14-41-50

16:31:25 [RRSAgent]

ACTION: KC to revert query-request from xs:all back to xs:seq and note this is due to limiations of XML Schema. [DONE] [2]

16:31:25 [RRSAgent]

recorded in http://www.w3.org/2005/10/04-dawg-irc#T14-41-58

16:31:25 [RRSAgent]

ACTION: Bijan to estimate impact of "abstract syntax entilemnt" etc. on WG test harness [3]

16:31:25 [RRSAgent]

recorded in http://www.w3.org/2005/10/04-dawg-irc#T15-37-57