16:47:07 RRSAgent has joined #rdb2rdf 16:47:07 logging to http://www.w3.org/2011/02/15-rdb2rdf-irc 16:47:09 RRSAgent, make logs world 16:47:09 Zakim has joined #rdb2rdf 16:47:11 Zakim, this will be 7322733 16:47:11 ok, trackbot; I see SW_RDB2RDF()12:00PM scheduled to start in 13 minutes 16:47:12 Meeting: RDB2RDF Working Group Teleconference 16:47:12 Date: 15 February 2011 16:47:19 Chair: Ivan 16:47:28 Regrets: Boris, Michael, Ashok 16:52:43 Regrets+ Sören 16:56:26 dmcneil has joined #RDB2RDF 16:58:37 SW_RDB2RDF()12:00PM has now started 16:58:44 +dmcneil 16:58:51 zakim, dial ivan-voip 16:58:51 ok, ivan; the call is being made 16:58:52 -dmcneil 16:58:52 +dmcneil 16:58:52 +Ivan 16:59:26 Topic: admin issues 16:59:40 +Alexandre 17:00:09 privera has joined #RDB2RDF 17:00:12 +EricP 17:00:55 cygri has joined #rdb2rdf 17:01:27 juansequeda has joined #rdb2rdf 17:01:41 +[IPcaller] 17:01:53 -EricP 17:01:55 +EricP 17:02:20 zakim, mute me 17:02:20 sorry, privera, I do not know which phone connection belongs to you 17:02:40 zakim, IPcaller is privera 17:02:40 +privera; got it 17:02:50 zakim, mute me 17:02:50 privera should now be muted 17:03:01 +Souri 17:03:32 Seema has joined #rdb2rdf 17:03:41 Souri has joined #rdb2rdf 17:03:59 zakim, who is here? 17:04:00 On the phone I see dmcneil, Ivan, Alexandre, EricP, privera (muted), Souri 17:04:02 On IRC I see Souri, Seema, juansequeda, cygri, privera, dmcneil, Zakim, RRSAgent, ivan, betehess, LeeF, MacTed, iv_an_ru, trackbot, ericP 17:04:15 + +1.603.897.aaaa 17:04:32 Zakim, aaaa is Seema 17:04:32 +Seema; got it 17:04:50 +mhausenblas 17:05:16 zakim, mhausenblas is cygri 17:05:16 +cygri; got it 17:05:32 zakim, pick a victim 17:05:32 Not knowing who is chairing or who scribed recently, I propose dmcneil 17:06:00 scribenick: dmcneil 17:06:13 dmcneil: i can scribe 17:06:15 ... but i need to know the incantations 17:06:22 Ashok has joined #rdb2rdf 17:07:00 topic: admin 17:07:12 ivan: starting meeting with admin 17:07:18 last week's minutes: http://www.w3.org/2011/02/08-rdb2rdf-minutes.html 17:07:20 +Ashok_Malhotra 17:07:54 i second minutes 17:07:57 +1 17:07:59 ivan: meetings are accepted 17:08:12 ivan: minutes are accepted 17:08:38 ivan: test cases are on the agenda, but Boris sent his regrets 17:08:52 ivan: any test case related issues for the call? 17:09:08 /me would like to thank Boris for participating to http://this-db-really.does-not-exist.org/ 17:09:09 ericP: we can still try out the test cases and see if they make sense 17:09:27 ivan: proposes moving to R2RML issues 17:09:28 Topic: R2RML 17:09:32 RESOLUTION: Minutes from last week are accepted 17:09:55 We can discuss ISSUE-23 raised by David 17:10:09 ISSUE-23? 17:10:09 ISSUE-23 -- Make tableOwner optional -- raised 17:10:09 http://www.w3.org/2001/sw/rdb2rdf/track/issues/23 17:10:37 scribenick: ericP 17:11:13 dmcneil: current R2RML spec requires the tableowner set when using tablename 17:11:14 q? 17:11:16 q+ 17:11:21 ack Souri 17:11:32 ... propose to make it optional to reflect SQL practice 17:11:45 Souri: discussed with seema and @@1. 17:11:59 ... it makes sense for it to be optional 17:12:32 ... at query processing time, we'll be connected so we can resolve this via a query time binding 17:12:45 ivan: clear what doc mod is required? 17:12:55 Souri: yep, we just change the cardinality 17:13:03 q+ to ask about SQL connectivity 17:13:18 +1 from me 17:13:41 scribenick: dmcneil 17:13:57 PROPOSE: make rr:tableOwner property optional (that is, have a cardinality of 0 or 1) 17:14:04 Souri: Recommends that the WG accept the proposed solution to Issue-23 17:14:06 +1 17:14:09 +1 17:14:12 +1 17:14:16 +1 17:14:21 RESOLVED: make rr:tableOwner property optional (that is, have a cardinality of 0 or 1) 17:16:12 cygri: do we need to keep an issue open to include this in testing? (paraphrased by ericP) 17:17:02 Ashok: ISSUE-23 is not open, create an action to apply it 17:17:05 ACTION: Souri to implement the conditionality of table ownder 17:17:05 Sorry, couldn't find user - Souri 17:17:10 sdas2 17:17:39 ACTION: sdas2 to implement the conditionality of table ownder 17:17:39 Created ACTION-103 - Implement the conditionality of table ownder [on Souripriya Das - due 2011-02-22]. 17:17:54 ISSUE-92? 17:17:54 ISSUE-92 does not exist 17:18:05 ACTION-92? 17:18:05 ACTION-92 -- Richard Cyganiak to address the R2RML - DM connection -- due 2011-02-08 -- OPEN 17:18:05 http://www.w3.org/2001/sw/rdb2rdf/track/actions/92 17:18:40 cygri: haven't done it yet, quite a bit of traffic on mailing list, need to think about how to do it in the document 17:19:12 cygri: there was a discussion about whether there should be a primer, or something that explains how the working group deliverables work together 17:19:14 q+ 17:19:18 + +575737aabb 17:19:26 zakim, aabb is me 17:19:26 +juansequeda; got it 17:19:28 cygri: perhaps this could be addressed in the primer (or overview doc) 17:19:59 q+ 17:20:03 cygri: or we could just add a bit of text to each of the docs 17:20:23 ack ivan 17:20:27 q- 17:20:47 ericP: withdraws question regarding whether a connection exists at times of query rewriting 17:21:11 ivan: strongly in favor of an overview/primer document 17:21:32 ack Ashok 17:21:44 Ashok: yes, we should write a primer, but people might not read it 17:21:53 q+ 17:22:06 Ashok: also, add at least one paragraph to each doc talking about the relationships between the docs 17:22:24 OWL primer? 17:22:25 ivan: may not agree 17:22:28 http://www.w3.org/TR/owl2-overview/ 17:23:10 ivan: points to the OWL document that is brief (1.5 pages) that shows how all of the pieces fit together 17:23:17 +1 to an overview document 17:23:23 ivan: this document was well received 17:23:23 q+ 17:23:32 ack ivan 17:23:35 q+ to comment quickly on how we could use the spec grouping feature, like http://www.w3.org/standards/techs/rdfrel.html#w3c_all 17:23:50 ack cygri 17:24:40 cygri: probably a short document because there is not a long list of deliverables (like OWL), but it will make it seem more complicated 17:24:54 cygri: if it can be addressed easily in the main document, then it is a good idea 17:25:13 cygi: the main documents are Direct Mapping and R2RML documents 17:25:35 cygri: different paragraph in each referring to the other 17:26:04 q+ 17:26:05 cygri: this would produce a more usable set of documents 17:26:40 cygri: could try putting the content in the wiki and then assess whether it warrants a separate document 17:26:43 ack betehess 17:26:43 betehess, you wanted to comment quickly on how we could use the spec grouping feature, like http://www.w3.org/standards/techs/rdfrel.html#w3c_all 17:27:09 http://www.w3.org/standards/techs/rdfrel.html#w3c_all 17:27:16 betehess: it is possible to create a new group to have all the specification in one group 17:27:40 q? 17:27:46 betehess: dependencies between documents is difficult to manage 17:28:11 ack Souri 17:28:12 q+ 17:28:29 q- 17:28:51 Souri: the R2RML document needs to be extended to describe how direct mappings can be used in a custom mapping 17:29:00 /me would like to recall we'll also have a document for the tests 17:29:09 Souri: need examples/test cases that show such hybrid mappings, this could go in a "primer" 17:29:31 ivan, open an issue :-) 17:29:34 q+ 17:29:43 ack ericP 17:29:44 illustrating hybrid mappings (some portion R2RML, some portion DM) 17:29:50 q+ 17:30:05 q+ 17:30:06 ericP: currently the Direct Mapping refers to the R2RML spec 17:30:23 ack juansequeda 17:30:29 ericP: the R2RML spec will need a reference to the Direct Mapping for the feature of using Direct Mappings in a custom mapping 17:30:35 ericP: so this will be covered anyway 17:30:54 ack ivan 17:30:57 juansequeda: short, summary document could be a good thing for the wider community 17:31:41 ivan: a summary document that clearly shows where to start reading makes sense 17:32:11 ACTION-93? 17:32:11 ACTION-93 -- Souripriya Das to identify not-mapping vs. default-mapping issues in R2RML/DM (Wiki or via mail) -- due 2011-02-08 -- OPEN 17:32:11 http://www.w3.org/2001/sw/rdb2rdf/track/actions/93 17:32:13 ivan: re-interpret ACTION-92 to be write proposed content on the wiki 17:32:38 Souri: discussed general approach last week, haven't worked on it much, not difficult to get done 17:32:45 ACTION-97? 17:32:45 ACTION-97 -- Richard Cyganiak to look into D2RQ implementation and update http://www.w3.org/2001/sw/rdb2rdf/wiki/Entity_disambiguation -- due 2011-02-08 -- OPEN 17:32:45 http://www.w3.org/2001/sw/rdb2rdf/track/actions/97 17:32:47 Souri will write down more details 17:32:58 on Action-93 17:33:41 cygri: ACTION-97 is to document how D2RQ supports translation tables 17:34:02 ivan: why is this relevant? 17:34:44 cygri: charter requires that we try and re-use entity URIs, question is how to get external URIs into the output of the mapping 17:34:48 ACTION-96? 17:34:48 ACTION-96 -- Richard Cyganiak to capture this (multiple subject maps) and other (future) potential error cases in the Wiki (ISSUE-16) -- due 2011-02-08 -- OPEN 17:34:48 http://www.w3.org/2001/sw/rdb2rdf/track/actions/96 17:35:12 ISSUE-16? 17:35:12 ISSUE-16 -- Should we allow multiple subjects for a logical table row? Also, what if no subject is specified? -- open 17:35:12 http://www.w3.org/2001/sw/rdb2rdf/track/issues/16 17:35:44 cygri: ACTION-96 - since R2RML is expressed in RDF and there is not a schema that clearly expresses what is valid, wanted to collect cases where cardinality was violated 17:36:09 cygri: we decided to collect such cases on a wiki page (e.g. "problem multiple subject maps") 17:36:29 cygri: for each of those we could document the solution (e.g. "raise error", etc.) 17:36:30 -juansequeda 17:36:33 juansequeda_ has joined #rdb2rdf 17:36:52 cygri: then we could use the wiki page contents to drive the specs 17:37:08 +juansequeda 17:37:10 cygri: agrees to keeping this action item open 17:37:39 We need to prioritize ... and in my opinion, Primer should come later (we can start on it, but), we need to push out the next draft sooner 17:37:45 ivan: the R2RML editor's draft is quite different from the official draft 17:37:49 q+ 17:37:54 q+ 17:37:58 ivan: when can we produce the next official draft 17:38:21 ack Souri 17:38:27 ivan: the gap between the two drafts is so large that an updated draft needs to be done soon 17:38:53 Souri: agrees, and thinks the official draft can be updated with issues marked 17:39:15 ack cygri 17:39:23 Souri: ISSUE-93 - the constructs for hybrid maps is still not defined, but this can be marked as still "in progress" 17:39:38 + +1.512.484.aacc 17:39:44 -juansequeda 17:39:58 cygri: there has been good progress on the Direct Mapping, might be a draft soon, might be able to publish them together? 17:39:58 we should fix a date where we publish both documents 17:40:17 +1 to ivan :-) 17:40:23 +1 to publishing at same time 17:40:26 ivan: very much in favor of publishing the two documents together, let's return to the Direct Mapping in a moment 17:40:38 zakim, aacc is juansequeda 17:40:38 +juansequeda; got it 17:40:49 ivan, we should publish the test-suite NOTE 17:41:11 is that juan talking? 17:41:38 juansequeda: will be traveling to Chile soon and will get a large amount of work done then 17:41:47 -juansequeda 17:41:50 juansequeda: on the Direct Mapping doc (?) 17:41:59 15-Mar-2010? 17:42:03 2011 17:42:08 Topic: Direct Mapping 17:42:18 ivan: let's not fix a precise date now 17:42:19 +juansequeda 17:42:27 ACTION-98? 17:42:27 ACTION-98 -- Juan Sequeda to rename Issue 11 and fix it in the DM -- due 2011-02-08 -- OPEN 17:42:27 http://www.w3.org/2001/sw/rdb2rdf/track/actions/98 17:42:31 ivan: on to the Direct Mapping, 3 open actions 17:42:33 juansequeda has joined #rdb2rdf 17:42:50 ISSUE-11? 17:42:50 ISSUE-11 -- Primary Key is a Foreign Key -- open 17:42:50 http://www.w3.org/2001/sw/rdb2rdf/track/issues/11 17:43:08 juansequeda: I did ACTION-98 already 17:43:44 juansequesa: this issue was where "foreign key" was incorrectly typed as "candidate key" in the spec 17:43:52 ACTION-99? 17:43:52 ACTION-99 -- Juan Sequeda to change ISSUE-13 to postponed and add ref from ISSUE-11 to ISSUE-13 -- due 2011-02-08 -- OPEN 17:43:52 http://www.w3.org/2001/sw/rdb2rdf/track/actions/99 17:44:05 juansequeda: the issue is still open (re ACTION-98) 17:44:08 Trackbot, Close ACTION-98 17:44:08 ACTION-98 Rename Issue 11 and fix it in the DM closed 17:44:12 ACTION-102? 17:44:12 ACTION-102 -- Ted Thibodeau to sum up the possibilities for generating reliable URIs for DM (to avoid bNodes) on the Wiki -- due 2011-02-15 -- OPEN 17:44:12 http://www.w3.org/2001/sw/rdb2rdf/track/actions/102 17:44:52 ivan: ACTION-102 still open because Ted is not here 17:45:01 ivan: what is the status of the Direct Mapping? 17:45:42 ericP: there is not much new information, new information will come from Juan's work in Chile (with Marcello (?)) 17:46:23 ericP: an open question is whether the Direct Mapping produces persistent identifiers for rows without primary keys 17:46:52 juansequeda: there is still an open issue related to avoiding blank nodes 17:47:28 juansequeda: there are several issues that we can begin discussing: e.g. hierarchical relationships, etc. 17:47:42 the denotational semantics does *not* need a primary key and uses bnode very well https://dvcs.w3.org/hg/FeDeRate/file/0407570a9826/directmapping/src/main/scala/DirectMapping.scala#l37 17:47:45 ivan: would like to come back to the publication issue before the end of the call 17:47:54 ivan: what open issues to dicsuss now? 17:48:16 ericP: maybe we can knock off the "primary key is a foreign key" issue 17:49:27 you can try hier_table in http://this-db-really.does-not-exist.org/ with and without "Detects hierarchy relation" 17:49:36 ericP: there was a model for the mapping, the considered the case of whether a primary key is also a foreign key, this is one of the 3 ways users express hierarchies in RDBMS, created a solution for expressing this in the mapping 17:50:46 ericP: the behavior with "detects hierarchy" turned off is the simple behavior 17:50:49 q+ to discuss the three possible cases 17:51:07 ack juansequeda 17:51:07 juansequeda, you wanted to discuss the three possible cases 17:51:12 ericP: the proposal is that this simple behavior be the behavior that is implemented when a primary key is a foreign key 17:51:42 juansequeda: there are three possibilities: 1) always detect hierarchy 2) never detect as hierarchy 3) make it an option to detect this as a hierarchy 17:52:01 ivan, yes 17:52:04 ivan: how would option "3" work, the beauty of the Direct Mapping is it just works 17:52:16 juansequeda: there could be "flavors" of direct mappings 17:52:17 q+ to say I'm against any switch 17:52:33 ivan: would rather not see a switch (personal opinion) 17:52:44 ack betehess 17:52:44 betehess, you wanted to say I'm against any switch 17:52:55 betehess: agrees with ivan 17:53:22 q+ 17:53:23 q+ 17:53:38 +1 to have only one flavour. if you want switches, go to r2rml, it has plenty 17:53:43 betehess: put the switch into the demo application to show what is being discussed, not to advocate for a switch in the Direct Mapping 17:53:46 ack ivan 17:54:13 ivan: proposes publishing the document with the simplest approach, put in a statement that this is still an open issue, ask community for feedback 17:54:19 ack juansequeda 17:54:21 sounds like a wise proposal 17:54:23 q+ to say we've already done one round without feedback 17:54:26 juansequeda: agrees with ivan 17:54:30 ack ericP 17:54:30 ericP, you wanted to say we've already done one round without feedback 17:54:35 +1 17:54:36 Ashok: agrees with ivan 17:54:48 ericP: we tried that, and the community did not respond 17:55:01 ericP: so proposes that we just go with the simple solution 17:55:15 ivan: has no problem with that 17:56:15 ericP: the compromise is that most primary keys appear as literals in the output triples 17:56:39 ericP, which example are you talking about? 17:56:51 ericP: but id the PK is also a FK then it appears only as a reference to another tuple 17:57:33 s/tuple/triple/ 17:58:49 cygri: in general agrees with proposal to proceed, there wasn't a really clear answer, so simplest is safest 17:59:13 To me pk=fk case seems to indicate presence of a simple 1:1 join between a parent table and a child table (which often appears in a normalized DB design) ... is there much more to it? 17:59:15 PROPOSAL: unary primary keys which are also foreign keys are treated exactly as other unary foreign keys 17:59:18 for the record, this is were we don't take unary foreign key in the scalars function: https://dvcs.w3.org/hg/FeDeRate/file/0407570a9826/rdb/src/main/scala/RDB.scala#l129 17:59:30 s/is were/is where/ 17:59:44 +1 17:59:49 +1 18:00:11 s/were/where/ 18:00:15 +25 18:00:15 +1 18:00:17 +1 18:00:18 +1 18:00:20 RESOLVED: unary primary keys which are also foreign keys are treated exactly as other unary foreign keys 18:00:22 0 (not fully clear) 18:00:41 ivan: can we stay on for a few minutes to discuss publishing Direct Mapping 18:01:15 q+ to suggest we lose review attention 18:01:25 ivan: proposes that the Direct Mapping document be published at the same time as the R2RML document without the Chilean work from Juan 18:01:27 are the r2rml people ready to publish too? 18:01:38 ack ericP 18:01:38 ericP, you wanted to suggest we lose review attention 18:01:45 juansequeda: progress has been made since the current workign draft 18:01:48 q+ 18:02:12 ack ivan 18:02:12 ericP: fears publishing document with few changes because it endangers the public review capacity 18:02:20 I am ok with publishing R2RML next draft alone 18:02:52 +1 to ivan comment re: publication of both documents makes sense 18:02:55 ivan: agrees with respect to Direct Mapping, but R2RML doc has changed a lot, needs to be published soon, is a good habit to publish them together 18:03:44 betehess: agrees with ivan 18:03:55 ericP: thinks the review capacity is more important 18:04:04 ivan: meeting is adjourned 18:04:06 +1 to member:ivan comment re: publication of both documents makes sense 18:04:08 great job dmcneil! 18:04:14 -Seema 18:04:21 PROPOSED: dmcneil is scribe for life 18:04:22 Ashok: will publish minutes 18:04:23 bye 18:04:27 zakim, bye 18:04:27 leaving. As of this point the attendees were dmcneil, Ivan, Alexandre, EricP, privera, Souri, +1.603.897.aaaa, Seema, cygri, Ashok_Malhotra, +575737aabb, juansequeda, 18:04:27 Zakim has left #rdb2rdf 18:04:30 +25 18:04:30 ... +1.512.484.aacc 18:04:42 resolved 18:04:42 rrsagent, make logs public 18:04:55 ericP, I think dmcneil has been the best scribe ever! 18:04:57 rrsagent, draft minutes 18:04:57 I have made the request to generate http://www.w3.org/2011/02/15-rdb2rdf-minutes.html Ashok 18:17:38 privera has left #RDB2RDF 18:24:29 cygri has joined #rdb2rdf 18:25:47 cygri has joined #rdb2rdf