13:58:53 RRSAgent has joined #sparql 13:58:53 logging to http://www.w3.org/2012/03/27-sparql-irc 13:58:55 RRSAgent, make logs world 13:58:55 Zakim has joined #sparql 13:58:57 Zakim, this will be 77277 13:58:57 ok, trackbot; I see SW_(SPARQL)10:00AM scheduled to start in 2 minutes 13:58:58 Meeting: SPARQL Working Group Teleconference 13:58:58 Date: 27 March 2012 13:59:05 zakim, this is 77277 13:59:05 ok, AndyS; that matches SW_(SPARQL)10:00AM 13:59:15 zakim, who is on the phone? 13:59:15 On the phone I see pgearon, [IPcaller] 13:59:22 zakim, IPCaller is me 13:59:22 +AndyS; got it 13:59:46 cbuilara has joined #sparql 13:59:50 AxelPolleres has joined #sparql 14:00:21 trackbot, start meeting 14:00:23 +Olivier_ 14:00:23 RRSAgent, make logs world 14:00:25 Zakim, this will be 77277 14:00:25 ok, trackbot; I see SW_(SPARQL)10:00AM scheduled to start now 14:00:26 Meeting: SPARQL Working Group Teleconference 14:00:26 Date: 27 March 2012 14:00:29 SteveH_ has joined #sparql 14:00:40 MattPerry has joined #sparql 14:01:43 Zakim, who's on the phone? 14:01:44 I notice SW_(SPARQL)10:00AM has restarted 14:01:44 On the phone I see pgearon, AndyS, Olivier_, +43.517.073.aaaa, kasei, ??P6 14:01:49 agenda: http://lists.w3.org/Archives/Public/public-rdf-dawg/2012JanMar/0276.html 14:01:51 Zakim, ??P6 is me 14:01:51 +SteveH; got it 14:02:08 chair: AxelPolleres 14:02:18 +MattPerry 14:02:31 cbuilara has joined #sparql 14:02:55 scribe: PaulGearon 14:03:02 +??P14 14:03:06 Zakim, who is on the phone? 14:03:06 On the phone I see pgearon, AndyS, Olivier_, +43.517.073.aaaa, kasei, SteveH, MattPerry, ??P14 14:03:10 zakim, ??P14 is me 14:03:10 +cbuilara; got it 14:03:16 Zakim, aaaa is me 14:03:16 +AxelPolleres; got it 14:03:27 Zakim, who is on the phone? 14:03:28 On the phone I see pgearon, AndyS, Olivier_, AxelPolleres, kasei, SteveH, MattPerry, cbuilara 14:03:41 chimezie has joined #sparql 14:04:16 AxelPolleres: goal for this week is discussing the further procedures for publications of the 3 docs coming up for last call 14:04:21 topic: admin 14:04:39 PROPOSED: Approve minutes at http://www.w3.org/2009/sparql/meeting/2012-03-20 14:04:56 +sandro 14:05:03 RESOLVED: Approve minutes at http://www.w3.org/2009/sparql/meeting/2012-03-20 14:05:30 +LeeF 14:05:36 Next regular meeting: 2012-04-03 @ 15:00 UK / 10:00 EST any regrets? 14:05:44 +chimezie 14:05:45 regrets form axel 14:05:58 Zakim, mute me 14:05:58 chimezie should now be muted 14:06:24 AxelPolleres: news from the RDF WG? 14:06:24 topic: rdf liaison 14:06:33 working towards LC for turtle 14:06:44 AndyS: working towards LC for Turtle, nothing special 14:06:51 agenda: http://lists.w3.org/Archives/Public/public-rdf-dawg/2012JanMar/0276.html 14:07:26 topic: next publications 14:07:32 subtopic: CSV/TSV 14:07:47 AxelPolleres: AFAICT we have the necessary reviews 14:07:59 AxelPolleres: ACTION 593 594 14:08:43 AxelPolleres: 593 was just completed today. 2 small issues that have been resolved. Have not yet checked the updates in 594, but that has been done 14:08:58 AndyS: ready to publish 14:09:23 kasei: yes, ready to publish 14:09:27 PROPOSE: to publish CSV/TSV as LC 14:09:43 +1 14:09:50 +1 IE 14:09:52 +1 (siemens) 14:09:54 +1 ASF 14:09:55 +1 Revelytix 14:09:56 +1 (Oracle) 14:09:57 +1 W3C 14:09:57 aye 14:09:58 +1 INRIA 14:10:18 Zakim, who is on the phone? 14:10:18 On the phone I see pgearon, AndyS, Olivier_, AxelPolleres, kasei, SteveH, MattPerry, cbuilara, sandro, LeeF, chimezie (muted) 14:10:35 +1 Garlik/Experian 14:11:21 RESOLVED: publish CSV/TSV as LC 14:11:30 AxelPolleres: date TBD 14:11:47 7 +1, no objections or abstentions 14:12:02 subtopic: overview 14:12:24 +EricP 14:12:56 AxelPolleres: only managed yesterday to finish. Some small examples. Will not have time to work on this document any more 14:13:02 Probably! 14:13:08 AxelPolleres: Lee, can you do the review int he next week? 14:13:16 Lee to review within the coming week. 14:13:40 AxelPolleres: more comments/questions on the overview doc? Else wait for review 14:13:48 subtopic: query 14:14:14 AxelPolleres: resolution from last week, discussed in mail from kasei 14:14:20 In fairness, last week we did NOT discuss the ALLPATHS(...) option or the default semantics, so I think Greg's comments were well in order 14:14:31 AxelPolleres: could kasei summarize concern? 14:15:03 kasei: concerned with path speccing 2 semantics, and then providing syntactic preference for one over the other 14:15:09 isn't the exhaustive semantics the default for the rest of query? 14:15:18 http://lists.w3.org/Archives/Public/public-rdf-dawg/2012JanMar/0272.html 14:15:33 kasei: this is premature since we don't know which is the semantics that will be more desirable 14:15:34 i'd expect that changing that default for one part of the language would be surprising for users 14:15:48 ericP, yes, which is why that was how our design went for pp, too, but we now have significant feedback that for pp non-counting often makes more sense 14:15:50 much as UNION ALL is catches SQL users up 14:15:56 I believe there is a preferred semantics. 14:16:21 q? 14:16:25 EricP - the comments do not align with your point. 14:16:35 kasei: suggest DISTINCT/ALL PATHS as keywords. But concerned we're making the decision without any basis and I think that will come back to bite us 14:17:01 AndyS: another concern. The info brought to the WG last time was that all commentors had been contacted and were OK with the approach 14:17:02 h 14:17:17 Right, not all commenters have been contacted 14:17:22 AndyS: but the last contact was in Feb and isn't the latest 14:17:50 AndyS: and one commenter was not contacted 14:18:23 AxelPolleres: one contacted was in touch and said he was OK with suggested semantics 14:18:36 AxelPolleres: did not contact "Yin" (?) 14:19:15 s/Yin/Jeen/ 14:19:21 AxelPolleres: point of discussion was that semantics on paths was OK for them 14:19:48 action 600? 14:19:48 Sorry, bad ACTION syntax 14:20:19 AxelPolleres: danger is if we do not proceed with resolution from last week, then we may lock, and may end up having to do the entire discussion again 14:20:23 q? 14:21:35 q+ 14:21:43 kasei: not suggesting that default should be one or the other. We don't have the data to make the decision yet 14:22:08 grep suggests to have both keywords fom path expressions ALLPATHS( ) and DISTINCT( ) 14:22:08 that's reasonably conservative 14:22:09 kasei: suggest using both keywords, and leave it up to implementations as to what to do if neither keyword is used 14:22:23 takes up one new token in the grammar 14:22:38 +1 on kasei's idea 14:23:25 Sandro: we can use AT RISK so that if we get pushback from devs then we can choose which way to go at the end of CR 14:23:47 Sandro: so we can put off the decision for now 14:24:07 (or, really, we can easily backtrack on this decision, if we mark it AT RISK.) 14:24:16 AxelPolleres: should we have a straw poll on this question? 14:24:37 sandro, are you suggesting that the entire PP syntax would be at risk? I'm not sure what would be left below the 'at risk' part... 14:25:17 how about "At risk: property paths require either the keyword DISTINCT or ALL to specify an exhaustive exploration of the path solutions. One of these keywords may be removed, making that semantics the default semantics for bare paths in graph patterns"? 14:25:32 PROPOSED: Add alternative DISTINCT() and ALLPATHS() modifiers around full property paths to SPARQL 1.1 Query as an AT RISK feature, and add work on counting & non-counting operators or partial paths to the future work list 14:25:32 (for the text in Query) 14:25:40 -1 14:27:10 AndyS: concerned we're just punting it to a later time 14:27:23 how about "At risk: property paths require either the keyword DISTINCT or ALL to specify an exhaustive exploration of the path solutions. One of these keywords may be removed during CR, making that semantics the default semantics for bare paths in graph patterns. The SPARQL WG would appreciate relevent feedback to public-sparql-comments@w3.org from users and implementors."? 14:27:31 q? 14:27:37 AxelPolleres: if it's AT RISK then there's no fallback 14:27:47 (specifies "during CR" and adds the plea for comments) 14:28:03 AxelPolleres: current fallback is the LC document 14:28:12 Sandro: the other fallback is to remove it completely 14:28:14 +q 14:28:36 Sandro: reminded recently that PP is a time permitting feature 14:29:08 Sandro: trying to get an extension on the WG charter. This is hard to justify for a "time permitting" feature 14:29:41 AndyS: commenters are saying something reasonably clear: there IS a preferred set of semantics 14:30:08 AndyS: from outside, for *+ then non-counting makes more sense. It's more intuitive 14:30:37 AndyS: referring to the comments on list. There are 3 on the list 14:30:51 AxelPolleres: the Chilleans indicate they want an existential on the whole path 14:31:09 AxelPolleres: they want a non-counting semantics 14:31:37 AxelPolleres: Jeen is more towards what AndyS is saying. 14:31:40 i note that our comment solicitation encourages only comments from those who aren't content with an ALL semantics 14:31:53 AndyS: Chilean paper is very much around * 14:32:00 http://www.dcc.uchile.cl/~jperez/papers/www2012.pdf 14:32:01 (here's a doc, whine if you don't like it) 14:32:18 s/whine/shout/ 14:32:34 AndyS: not that other things aren't mentioned. It's a question of emphasis 14:32:52 AxelPolleres: paper discusses existential on paths. 14:33:09 AxelPolleres: "cardinality of this mapping would be one" 14:34:18 AxelPolleres: with resolution from last time we can deal with this semantics just by putting DISTINCT around the expression 14:35:08 Sandro: according to AndyS, we can just change the semantics to meet the comments. Don't need any new keywords 14:35:12 AndyS: yes 14:35:19 * + alone dont make existential semantics. 14:35:24 AxelPolleres: can't get existential semantics just by changing * + 14:35:44 AxelPolleres: Chileans don't want mixed semantics 14:35:51 AndyS: where's that in the paper? 14:36:04 sandro: there's no need to follow that paper 14:36:25 AxelPolleres: the problem is if WE are happy with things 14:37:05 AxelPolleres: addressing discussion from the week. Started by kasei, and includes AndyS and AxelPolleres 14:37:23 AxelPolleres: are we happy with resolution from last week? 14:37:50 AxelPolleres: will kasei (or anyone else) want to lie down in the road over this issue? 14:38:12 kasei: from my understanding of the resolution last week is a problem for me 14:38:28 kasei: but there appears to be more to the resolution than what I read in the minutes 14:38:46 what we resolved to was Option 3 http://www.w3.org/2009/sparql/meeting/2012-03-20#line0225 14:38:47 AxelPolleres: last week we went with option 3 14:39:21 AxelPolleres: adding DISTINCT around full paths only. Other than that we leave the semantics. So the default semantics is around counting 14:39:42 AxelPolleres: DISTINCT changes to an existential semantics 14:40:34 AxelPolleres: proposal is to add an ALL keyword. kasei's concern is that the resolution has a lock-in to 1 default semantics 14:41:11 I prefer option 6. One implementation. Lower support costs. Natural semantics. Least block on future work. Mixed counting is the minimal way forward. 14:41:17 the option to have both syntaxes with a later determination of which is the default seems more appealing to me now 14:41:51 esp. if both syntaxes/semantics can be (easily) made mutually exclusive 14:42:03 it was a condorcet voting implementation. 14:42:40 my order of prefs: default ALL, require DISTINCT & ALL, default DISTINCT 14:42:45 AxelPolleres: could add a switch at the query level, but probably don't want to add that as well 14:42:56 (descending order) 14:44:14 We have various intuitions floating around on what is "intuitive", I am afraid 14:44:17 AndyS: 2 classes of operations. Simple like sequence and alternation. Then others like working on arbitrary length paths 14:44:48 AndyS: what are the natural expectations and work with that, even if it means different counting in different places 14:45:06 +LeeF.a 14:45:10 AndyS: so far we have failed to find what the expectations are in various situations 14:46:09 AxelPolleres: agree with have subtleties on the lower levels, but think our approach can address can address 2 of the 3 concerns 14:46:30 default ALL, require DISTINCT & ALL, default DISTINCT 14:47:16 +q 14:47:25 q- 14:48:44 Andy: is "/" also distinct for you, paul? 14:48:54 Paul: have to think about that. 14:49:42 Axel: the chileneans definition (p.8) in their paper makes "/" also distinct 14:49:59 q- 14:50:35 speculating that if our use cases also need / then counting semantics are more likely to be what we'd want 14:50:44 PROPOSED: require eithrt DISTINCT or ALL around paths 14:50:55 We can define { ?x :p/:q ?y } ==> { ?x :p ?a . ?a :q ?y } ie. not as PP, but merely syntax short form. PP is just *,+,? 14:51:03 +1 14:51:12 +1 14:51:13 +1 14:51:21 -1 14:51:40 (fails on implementation cost issues) 14:51:42 0 14:51:44 0 14:51:47 0 14:51:51 0 (like this, but would also want to allow syntax without a keyword and let the implementation decide the semantics) 14:51:56 +0 14:52:07 0 14:52:45 I would be open to Andy's new simplification 14:52:53 AndyS, what does (:p/:q)* do, then? 14:52:59 The standing resolution is still the one from last time. 14:53:09 AndyS: that would be DISTINCT 14:53:32 isn't just the combination of operations. DISTINCT over something that isn't leads to an overall DISTINCT 14:55:33 AxelPolleres: changing the behavior of * and + did not find a majority last time 14:55:56 I think last time we rejected addition of {*},{+},{?} 14:56:10 AndyS: approaching it from a minimal set of features and punt the rest to future work. This is why I'm suggesting getting rid of {} 14:56:34 AndyS: and also getting rid of counting features m/n 14:57:18 AxelPolleres: can construct use cases that need it. This is a proposal that covers less 14:57:27 s/AxelPolleres/AndyS/ 14:57:31 I'm in favor of the simplification. I'm not even sure how I would explain all these variations to a user. 14:58:11 AxelPolleres: shouldn't ignore discussion from today, but we're no further than the resolution from last time 14:58:40 -EricP 14:58:45 AxelPolleres: recall that this is a time-permitting feature and this should not hold up the WG any further 14:59:03 AxelPolleres: need to discuss in email during the coming week 14:59:11 let's take it to email 14:59:19 zakim, who is on the phone? 14:59:19 On the phone I see pgearon, AndyS, Olivier_, AxelPolleres, kasei, SteveH, MattPerry, cbuilara, sandro, LeeF, chimezie (muted), LeeF.a 14:59:41 adjourned 14:59:42 adjourned 14:59:51 -sandro 14:59:55 -Olivier_ 14:59:59 -cbuilara 15:00:01 rrsagent, make records public 15:00:09 -SteveH 15:00:11 -chimezie 15:00:15 -MattPerry 15:00:21 -kasei 15:00:23 -LeeF.a 15:00:31 -AxelPolleres 15:00:48 What are your requirements for a PP design? i.e. principles 15:00:58 -AndyS 15:01:10 -pgearon 15:02:04 Andy, maybe a good question we should try to summarize on the list for next week...I think Lee's summary was a good start, but admittedly, I think it left out the lock-in aspect that Greg now brought in. 15:02:24 need to run. 15:21:58 The Chileans may have said they didn't want mixed semantics, but I note their paper doesn't use any examples where that would be an issue. 15:22:27 They only discuss paths with * and + applied to a predicate (sometimes several times) 15:35:01 disconnecting the lone participant, LeeF, in SW_(SPARQL)10:00AM 15:35:02 SW_(SPARQL)10:00AM has ended 15:35:02 Attendees were pgearon, AndyS, Olivier_, +43.517.073.aaaa, kasei, SteveH, MattPerry, cbuilara, AxelPolleres, sandro, LeeF, chimezie, EricP 16:20:48 EricP, Sandro - issue with making PP informative is that any doc will still describe one implied semantics even if formally not "normative". Just writing an example will imply something. 17:31:17 Zakim has left #sparql