IRC log of rdb2rdf on 2010-11-30

Timestamps are in UTC.

16:52:43 [RRSAgent]
RRSAgent has joined #rdb2rdf
16:52:43 [RRSAgent]
logging to http://www.w3.org/2010/11/30-rdb2rdf-irc
16:52:44 [hhalpin]
hhalpin has changed the topic to: Meeting Nov. 30th
16:52:45 [trackbot]
RRSAgent, make logs world
16:52:45 [Zakim]
Zakim has joined #rdb2rdf
16:52:47 [trackbot]
Zakim, this will be 7322733
16:52:47 [Zakim]
ok, trackbot; I see SW_RDB2RDF()12:00PM scheduled to start in 8 minutes
16:52:48 [trackbot]
Meeting: RDB2RDF Working Group Teleconference
16:52:48 [trackbot]
Date: 30 November 2010
16:53:03 [mhausenblas]
Agenda: http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2010Nov/0155.html
16:53:14 [mhausenblas]
RRSAgent, draft minutes
16:53:14 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/11/30-rdb2rdf-minutes.html mhausenblas
16:53:19 [mhausenblas]
RRSAgent, make logs public
16:53:31 [boris]
boris has joined #rdb2rdf
16:59:21 [Ashok]
Ashok has joined #rdb2rdf
17:00:13 [nunolopes]
nunolopes has joined #RDB2RDF
17:00:33 [boris]
I have problem with the passcoe
17:00:34 [boris]
code
17:00:45 [Zakim]
SW_RDB2RDF()12:00PM has now started
17:00:47 [boris]
hi BTW
17:00:52 [Zakim]
+[IPcaller]
17:00:57 [boris]
yes
17:00:57 [Zakim]
+nunolopes
17:01:07 [Zakim]
+mhausenblas
17:01:13 [mhausenblas]
Zakim, who's here?
17:01:13 [Zakim]
On the phone I see [IPcaller], nunolopes, mhausenblas
17:01:14 [Zakim]
On IRC I see nunolopes, Ashok, boris, Zakim, RRSAgent, hhalpin, privera, ivan, mhausenblas, MacTed, LeeF, betehess, iv_an_ru, trackbot, ericP
17:01:24 [ivan]
zakim, dial ivan-voip
17:01:24 [Zakim]
ok, ivan; the call is being made
17:01:25 [Zakim]
+Ivan
17:01:32 [Zakim]
+Ashok_Malhotra
17:01:34 [mhausenblas]
Zakim, IPCaller is privera
17:01:34 [Zakim]
+privera; got it
17:01:38 [boris]
I'll try it again
17:01:41 [juansequeda]
juansequeda has joined #rdb2rdf
17:01:49 [nunolopes]
Zakim, mute me
17:01:49 [Zakim]
nunolopes should now be muted
17:02:01 [mhausenblas]
http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2010Nov/0155.html
17:02:01 [MacTed]
major deadline is hitting me here ... I may not make the call, and will be minimally attentive if I do.
17:02:01 [MacTed]
my review of the Direct Mapping Editor's Draft is *not* complete, in no small part because I find it very hard to work with onscreen, and it fails to print usefully (many elements print off-the-page)
17:02:11 [Zakim]
+[IPcaller]
17:02:31 [mhausenblas]
Zakim, who's here?
17:02:31 [Zakim]
On the phone I see privera, nunolopes (muted), mhausenblas, Ivan, Ashok_Malhotra, [IPcaller]
17:02:33 [Zakim]
On IRC I see juansequeda, nunolopes, Ashok, boris, Zakim, RRSAgent, hhalpin, privera, ivan, mhausenblas, MacTed, LeeF, betehess, iv_an_ru, trackbot, ericP
17:02:37 [juansequeda]
Zakim, IPcaller is me
17:02:37 [Zakim]
+juansequeda; got it
17:02:44 [Seema]
Seema has joined #rdb2rdf
17:02:45 [mhausenblas]
Zakim, pick a victim
17:02:46 [Zakim]
Not knowing who is chairing or who scribed recently, I propose Ashok_Malhotra
17:02:53 [mhausenblas]
Chair: Ashok
17:02:55 [mhausenblas]
Zakim, pick a victim
17:02:55 [Zakim]
Not knowing who is chairing or who scribed recently, I propose Ivan
17:03:09 [Souri]
Souri has joined #rdb2rdf
17:03:11 [cygri]
cygri has joined #rdb2rdf
17:03:28 [boris]
still with the passcode not valid
17:03:29 [boris]
weird
17:03:37 [cygri]
zakim, i'm with mhausenblas
17:03:37 [Zakim]
+cygri; got it
17:03:43 [Zakim]
+??P34
17:04:28 [mhausenblas]
scribenick: cygri
17:05:01 [cygri]
Topic: Admin
17:05:05 [Zakim]
+Seema
17:05:09 [boris]
I'm calling again ... sorry
17:05:12 [cygri]
PROPOSAL: Accept the minutes of last meeting, see http://www.w3.org/2010/11/16-rdb2rdf-minutes.html
17:05:14 [Ashok]
+ PROPOSAL: Accept the minutes of last meeting, see http://www.w3.org/2010/11/23-rdb2rdf-minutes.html
17:05:20 [juansequeda]
+1
17:05:23 [mhausenblas]
+1
17:05:36 [ivan]
0 :-)
17:06:12 [cygri]
RESOLUTION: Accept the minutes of last meeting, see http://www.w3.org/2010/11/23-rdb2rdf-minutes.html
17:06:14 [mhausenblas]
ACTION-79?
17:06:14 [trackbot]
ACTION-79 -- Juan Sequeda to compile a list of speaking/panel opportunities for diseminating rdb2rdf work -- due 2010-11-30 -- OPEN
17:06:14 [trackbot]
http://www.w3.org/2001/sw/rdb2rdf/track/actions/79
17:06:18 [Zakim]
+boris
17:07:27 [cygri]
Topic: Review of R2RML Test Cases
17:07:42 [Ashok]
2. Review of R2RML Test Cases (Boris) ACTION-81 http://www.w3.org/2001/sw/rdb2rdf/wiki/R2RML_Test_Cases
17:08:23 [cygri]
ashok: we agreed to postpone first test case?
17:08:26 [cygri]
boris: yes
17:08:46 [boris]
http://www.w3.org/2001/sw/rdb2rdf/wiki/R2RML_Test_Cases#R2RMLTC0002
17:09:00 [cygri]
... i'll start with test case R2RMLTC0003
17:09:58 [cygri]
... this is without primary key so URI is generated by concatenating values
17:10:29 [cygri]
ashok: are you speaking about default mapping?
17:10:33 [cygri]
boris: no
17:10:38 [Zakim]
+[IPcaller]
17:10:45 [hhalpin]
Zakim, [IPcaller] is hhalpin
17:10:45 [Zakim]
+hhalpin; got it
17:10:56 [ivan]
q+
17:11:00 [cygri]
... syntax of the R2RML mapping is at end of test case
17:11:01 [hhalpin]
Zakim, who's on the phone?
17:11:01 [Zakim]
On the phone I see privera, nunolopes (muted), mhausenblas, Ivan, Ashok_Malhotra, juansequeda, ??P34, Seema, boris, hhalpin
17:11:03 [Zakim]
mhausenblas has cygri
17:11:34 [ericP]
Zakim, please dial ericP-office
17:11:34 [Zakim]
ok, ericP; the call is being made
17:11:36 [Zakim]
+EricP
17:11:52 [mhausenblas]
q?
17:12:48 [ericP]
q+ to argue with ivan
17:13:10 [cygri]
ivan: i would consider the expected default mapping result as separate entry
17:13:29 [ivan]
ack ivan
17:14:11 [cygri]
ericP: the default mapping says, for any given schema+rows, here's the graph it entails
17:14:20 [ivan]
q+
17:14:25 [ivan]
ack ericP
17:14:25 [Zakim]
ericP, you wanted to argue with ivan
17:14:26 [cygri]
... how to test that your impl works is up to you
17:14:38 [cygri]
... you can do that test given an rdf graph
17:15:00 [cygri]
ivan: it's a question of organizing the tests
17:15:23 [juansequeda]
+1 to Ivan
17:15:37 [cygri]
... for each test we have a small db, we have a graph it produces, and optionally we have an r2rml mapping and the graph it produces
17:15:41 [cygri]
q+
17:15:48 [Zakim]
-boris
17:15:48 [ivan]
ack ivan
17:16:02 [boris]
I got disconnected
17:16:16 [boris]
calling again, sorry
17:16:21 [cygri]
ashok: does the syntax look right?
17:16:58 [hhalpin]
q+
17:17:13 [ericP]
+1
17:17:36 [ericP]
(to the notion that some tests will apply to either mapping)
17:17:37 [hhalpin]
+1, yes otherwise the test-cases for direct graph are likely to become rather redudant
17:17:38 [hhalpin]
q-
17:18:03 [ericP]
q+ to note that many tests use the same input db
17:18:10 [hhalpin]
q+
17:18:21 [ivan]
ack cygri
17:18:49 [hhalpin]
+1 cygri's comment
17:19:48 [ericP]
database [ directDB? ( r2rml r2rDB ) * ]
17:19:51 [ivan]
q+
17:19:56 [boris]
sorry, havin problems again
17:19:57 [cygri]
cygri: there might be many test cases where there are multiple customized mappings for the same db
17:20:00 [Souri]
In TC3, due to absence of primary key, the subject will be a bNode.
17:20:34 [Souri]
q?
17:20:39 [cygri]
... and in that case the direct graph would be same
17:20:56 [cygri]
... so it might be better to have one kind of test cases for direct, and another kind for r2rml
17:21:34 [cygri]
ericP: we would get lots of redundancy either way
17:21:40 [cygri]
... what would the reader find easiest
17:21:47 [cygri]
... databases are what we change the least
17:22:19 [cygri]
... propsed structure: have a db, then may or may not have direct mapping, then n pairs of r2rml and custom graph
17:22:22 [Souri]
My above comment was in relation to direct mapping (not R2RML mapping).
17:22:31 [ivan]
+1 to Ashok
17:22:43 [cygri]
ashok: why would we ever not have a direct mapping?
17:22:44 [ivan]
q-
17:22:48 [ivan]
ack ericP
17:22:48 [Zakim]
ericP, you wanted to note that many tests use the same input db
17:22:51 [hhalpin]
ack hhalpin
17:22:58 [cygri]
ericP: direct mapping might not be interesting for some dbs
17:23:02 [ivan]
+1 to to Eric, modulo the '?' mark:-)
17:23:08 [cygri]
+1 to Eric
17:23:15 [hhalpin]
hmm
17:23:16 [hhalpin]
mike not working
17:23:28 [hhalpin]
but basically, my point is that a direct graph mapping
17:23:32 [hhalpin]
should be the first part of the document
17:23:36 [hhalpin]
for each database, like eric said
17:23:41 [hhalpin]
and the the second part of the doc should cover
17:23:44 [hhalpin]
the features of r2rml.
17:23:50 [hhalpin]
Obviously, otherwise implementers
17:23:51 [hhalpin]
may be confused
17:24:01 [cygri]
+1 to that
17:24:02 [juansequeda]
+1
17:24:10 [hhalpin]
it seems kinda silly to have multiple test-cases
17:24:15 [hhalpin]
that have the same input-output
17:24:23 [hhalpin]
that's redundant, and makes the document harder
17:24:57 [cygri]
ericP: do we put all the db-direct pairs in the first half of the document?
17:25:09 [hhalpin]
It's just an organizational issues - but yes, we could do it by databases as well.
17:25:19 [ivan]
+1 to Ashok and Eric
17:25:29 [cygri]
+1 to hhalpin
17:25:32 [hhalpin]
However, the key is not to have any redundant test-cases, which the current approach would be absolutely full of.
17:26:02 [hhalpin]
So I'm happy with Eric's proposal of doing it one database at time, as long as there is no redundant tests.
17:26:03 [cygri]
Topic: Implementations (Michael)
17:26:10 [mhausenblas]
ACTION-82?
17:26:10 [trackbot]
ACTION-82 -- Michael Hausenblas to create Wiki page with implementation status (and plans thereof) -- due 2010-11-30 -- OPEN
17:26:10 [trackbot]
http://www.w3.org/2001/sw/rdb2rdf/track/actions/82
17:26:16 [mhausenblas]
close ACTION-82
17:26:17 [trackbot]
ACTION-82 Create Wiki page with implementation status (and plans thereof) closed
17:26:27 [ericP]
I note that we still have a dissenting opinion from cygri
17:26:31 [ericP]
do we want to resolve that?
17:26:51 [juansequeda]
I'm adding myself there
17:26:56 [cygri]
mhausenblas: made wiki page
17:26:57 [ericP]
(as in give him time to persuade us)
17:27:05 [cygri]
... http://www.w3.org/2001/sw/rdb2rdf/wiki/Implementations
17:27:22 [cygri]
... now lists D2RQ, FeDeRate, ODEMapster, Revelytix
17:27:41 [cygri]
ashok: Souri, will you add an oracle line?
17:28:05 [cygri]
Souri: we can't officially promise, so we'll implement it first and add then
17:28:08 [juansequeda]
now we have 5 lines :)
17:28:29 [cygri]
mhausenblas: it would be extremely beneficial if we had *something* from oracle
17:28:29 [ivan]
+1 to Michael
17:28:42 [cygri]
... "we intend to ..."
17:28:49 [cygri]
Souri: will se what we can do
17:29:01 [cygri]
Topic: R2RML status
17:29:31 [cygri]
Souri: we are waiting for review comments
17:29:41 [cygri]
... interesting comment from ????
17:29:48 [ivan]
-> http://www.w3.org/2001/sw/rdb2rdf/r2rml/ editors' draft of r2rml
17:30:04 [cygri]
... about blank nodes
17:30:19 [Seema]
comment from Percy on the r2rml spec
17:30:22 [cygri]
... no one can conflict with a blank node in the same graph
17:30:43 [cygri]
s/????/Percy/
17:31:13 [privera]
I'm a Master Student at Pontifical Catholic University of Rio de Janeiro (PUC-Rio)
17:31:18 [cygri]
... if we have stuff in different graphs, then we can't connect the triples because blank nodes in different graph are always distinct
17:31:25 [cygri]
... we need to point that out in the doc
17:31:52 [cygri]
... my plan for solution: cautionary note
17:31:56 [cygri]
+1
17:31:59 [cygri]
q+
17:32:13 [ivan]
ack cygri
17:32:58 [hhalpin]
+1 strong warning on blank nodes, or RDF supports Marcelo's suggested semantics for blank-nodes in RDF Next to avoid pathological blank node problems.
17:33:19 [cygri]
cygri: +1 to that, put a strong warning but if ppl want to use bnodes anyways why stop them
17:33:19 [privera]
+1
17:33:52 [cygri]
ashok: you start by talking about how r2rml can be used
17:34:09 [boris]
thanks to ericP I'm on the phone again
17:34:24 [cygri]
... there are two different uses. you could materialize the graph. or you make it virtual and query with sparql
17:34:48 [ivan]
q+
17:34:55 [cygri]
... there are words, but they are not focused
17:35:12 [hhalpin]
q+
17:35:37 [hhalpin]
q-
17:35:44 [cygri]
ashok: i'll propose wording
17:35:49 [hhalpin]
+1 just outlining options
17:36:01 [cygri]
... the document is very dense
17:36:07 [boris]
zakim, mute me
17:36:07 [Zakim]
sorry, boris, I do not know which phone connection belongs to you
17:36:08 [cygri]
... you want more words
17:36:31 [cygri]
... always add one or two sentences: this bit of sql here does the following
17:36:40 [Souri]
q+
17:36:57 [mhausenblas]
q?
17:37:06 [mhausenblas]
ack ivan
17:37:20 [cygri]
ivan: we need some text somewhere that explains the relationship between r2rml and direct mappign
17:37:38 [cygri]
... i made a presentation, it went well, but there's a need for explanation here
17:37:55 [cygri]
... titles are very different from another etc. we have to make a link between them
17:38:06 [cygri]
ashok: have a small paragraph in both of them
17:38:30 [cygri]
ivan: have a separate W3C note that explains it. can be a one-pager
17:38:53 [cygri]
... we did that in RIF and OWL (where we had six or seven docs)
17:38:58 [cygri]
... that might be one way to do it
17:39:08 [cygri]
ashok: my instinct is to add one paragraph in each doc
17:39:11 [hhalpin]
+1 one paragraph i each document rather than yet another note
17:39:15 [hhalpin]
minimize the number of documents
17:39:20 [cygri]
+1 to ivan and hhalpin
17:39:26 [Ashok]
q?
17:39:37 [cygri]
Souri: want to talk about adding schema triples
17:39:40 [cygri]
q+
17:40:05 [juansequeda]
+q
17:40:08 [cygri]
... should we always generate these triples? or make it an option that you can skip?
17:40:13 [ivan]
ack Souri
17:40:15 [ivan]
ack cygri
17:40:16 [Souri]
q-
17:40:23 [hhalpin]
q+
17:41:53 [ivan]
ack juansequeda
17:42:03 [cygri]
cygri: typically the schema triples would be defined in existing vocabulary documents
17:42:19 [cygri]
... and those might disagree with the r2rml-generated schema triples
17:42:25 [cygri]
... would like to understand the use case better
17:42:47 [cygri]
juansequeda: we should generate schema triples for direct mapping but not for r2rml
17:42:53 [Souri]
Suppose a query says {?x rdf:type rdfs:Class} and it goes against RDF "generated" from an empty EMP table ... what should be the response: should it be {?x = ".../EMP"} ?
17:43:11 [cygri]
hhalpin: -1 to having optional stuff or gray areas
17:43:57 [hhalpin]
ditto with metadata about triples in general
17:44:08 [juansequeda]
Marcelo and I have already defined the "direct schema": http://www.w3.org/2001/sw/rdb2rdf/wiki/Default_Mapping_to_RDFS/OWL
17:44:25 [hhalpin]
Have an option that tells you to generate it, and then we flip a coin to decide on the default.
17:44:28 [hhalpin]
:)
17:45:46 [ivan]
+1 to cygri
17:46:16 [hhalpin]
so maybe the default should be not to have the schema triples by default?
17:46:24 [ericP]
+1 to cygri
17:46:31 [juansequeda]
+1 to cygri
17:46:37 [boris]
+1 to cygri
17:46:45 [juansequeda]
hhalpin, I agree. schema triples should be optional
17:46:46 [hhalpin]
q+
17:46:59 [privera]
+1 to member:cygri
17:47:01 [cygri]
Souri: if we have empty table, what triples do we generate?
17:47:15 [cygri]
... do we generate nothing?
17:47:24 [hhalpin]
there's the "table triple" issue - there was a diff between Eric and J&M's draft there...
17:48:05 [hhalpin]
ack hhalpin
17:48:08 [ivan]
ack hhalpin
17:48:11 [cygri]
... just making sure that we are ok with generating no triples from an empty table
17:48:38 [cygri]
hhalpin: might be useful to have explicit option for generating schema triples
17:49:09 [cygri]
... there was something about table/metadata triples
17:49:58 [cygri]
ericP: cygri wanted to be able to identify which nodes comes from which database
17:50:10 [juansequeda]
table triple: <emp#1> <ex:table> <emp>
17:50:37 [cygri]
... there's several ways of doing this
17:50:50 [cygri]
... triple comes from a table? node comes from a table?
17:50:51 [privera]
but in that case we are start talking about provenance
17:50:52 [cygri]
q+
17:51:25 [cygri]
... i'm in favour of saying "this predicate comes from this table"
17:51:44 [Ashok]
s/database/table/
17:52:57 [juansequeda]
+1 to cygri
17:53:24 [cygri]
cygri: i want to be able to ask "what resources come from this table?" in a very simple way
17:53:34 [Souri]
Just to confirm: So I am assumig that we are okay with a query {?x rdf:type rdfs:Class}, against RDF triples generated from an empty table (with no rr:class use in R2RML mapping) would return no solutions.
17:53:39 [cygri]
ericP: i want to make provenance ppl happy
17:54:12 [cygri]
... and then the sparql query would have two triple patterns instead of one
17:54:30 [cygri]
... this would be a leaner graph
17:55:17 [cygri]
... instead of 10000 arcs saying "protein x comes from table y", you have 10 arcs saying "column y.a comes from table y"
17:55:50 [cygri]
Souri, i'm ok with that
17:56:00 [ericP]
<tableX> us:producedPredicate <predicateY> .
17:56:04 [mhausenblas]
RRSAgent, draft minutes
17:56:04 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/11/30-rdb2rdf-minutes.html mhausenblas
17:56:10 [Souri]
"what resources come from this table?" Richard, how (i.e., using what SPARQL graph pattern) would you like to express it?
17:56:19 [cygri]
Topic: Direct mapping
17:56:33 [cygri]
marcelo: nothing new this week
17:56:34 [ericP]
getting nodes from a table: SELECT ?s WHERE { <table> us:producedPredicate ?p . ?s ?p ?o }
17:56:43 [cygri]
ashok: thanks all
17:56:57 [cygri]
juansequeda: how far into december do we keep meeting?
17:57:11 [ivan]
I am on vacations on both dates
17:57:26 [ericP]
i intend to be lost in the desert on the 21st
17:57:28 [cygri]
ashok: telecons on 21st and 28th?
17:57:42 [mhausenblas]
Michael: +1 for 21, but -1 for 28
17:57:54 [Seema]
+1 for 21, no for 28
17:57:57 [cygri]
ashok: let's cancel both then
17:58:02 [privera]
+1 ->28
17:58:16 [Zakim]
-Seema
17:58:17 [Zakim]
-hhalpin
17:58:18 [ivan]
zakim, drop me
17:58:18 [Zakim]
Ivan is being disconnected
17:58:19 [Zakim]
-Ivan
17:58:32 [mhausenblas]
[adjourned]
17:58:42 [Zakim]
-nunolopes
17:59:16 [cygri]
RESOLUTION: telecons for 21st and 28th is cancelled
17:59:26 [mhausenblas]
RRSAgent, draft minutes
17:59:26 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/11/30-rdb2rdf-minutes.html mhausenblas
18:00:16 [Zakim]
-Ashok_Malhotra
18:00:26 [Zakim]
-juansequeda
18:01:20 [Zakim]
-privera
18:01:37 [Ashok]
rrsagent, make logs public
18:07:25 [Ashok]
present: privera, nunolopes, mhausenblas, Ivan, Ashok_Malhotra, Eric, Juan, Boris, Harry, Richard
18:07:37 [Ashok]
RRSAgent, draft minutes
18:07:37 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/11/30-rdb2rdf-minutes.html Ashok
18:09:18 [Zakim]
-??P34
18:32:32 [Zakim]
-mhausenblas
18:32:33 [Zakim]
-EricP
18:32:33 [Zakim]
SW_RDB2RDF()12:00PM has ended
18:32:35 [Zakim]
Attendees were nunolopes, mhausenblas, Ivan, Ashok_Malhotra, privera, juansequeda, cygri, Seema, boris, hhalpin, EricP
18:33:42 [mhausenblas]
RRSAgent, draft minutes
18:33:42 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/11/30-rdb2rdf-minutes.html mhausenblas
18:33:55 [mhausenblas]
trackbot, end telecon
18:33:55 [trackbot]
Zakim, list attendees
18:33:55 [Zakim]
sorry, trackbot, I don't know what conference this is
18:33:56 [trackbot]
RRSAgent, please draft minutes
18:33:56 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/11/30-rdb2rdf-minutes.html trackbot
18:33:57 [trackbot]
RRSAgent, bye
18:33:57 [RRSAgent]
I see no action items