IRC log of RDB2RDF on 2010-01-26

Timestamps are in UTC.

16:58:23 [RRSAgent]
RRSAgent has joined #RDB2RDF
16:58:23 [RRSAgent]
logging to http://www.w3.org/2010/01/26-RDB2RDF-irc
16:58:25 [trackbot]
RRSAgent, make logs world
16:58:25 [Zakim]
Zakim has joined #RDB2RDF
16:58:27 [trackbot]
Zakim, this will be 7322733
16:58:27 [Zakim]
ok, trackbot; I see SW_RDB2RDF()12:00PM scheduled to start in 2 minutes
16:58:28 [trackbot]
Meeting: RDB2RDF Working Group Teleconference
16:58:28 [trackbot]
Date: 26 January 2010
16:58:31 [Zakim]
SW_RDB2RDF()12:00PM has now started
16:58:38 [Zakim]
+??P10
16:58:58 [mhausenblas]
Agenda: http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2010Jan/0047.html
16:59:09 [Zakim]
+??P15
16:59:09 [Souri]
Souri has joined #rdb2rdf
16:59:13 [Zakim]
+ +1.512.471.aaaa
16:59:18 [mhausenblas]
Chair: Ahmed
16:59:23 [mhausenblas]
scribenick: whalb
16:59:27 [Zakim]
+whalb
16:59:30 [Marcelo]
Marcelo has joined #rdb2rdf
17:00:13 [nunolopes]
nunolopes has joined #RDB2RDF
17:00:14 [Zakim]
+??P24
17:00:39 [Zakim]
+mhausenblas
17:00:51 [Zakim]
+hhalpin
17:01:05 [soeren]
soeren has joined #RDB2RDF
17:01:14 [Zakim]
+ +49.322.222.0.aabb
17:02:04 [soeren]
zakim, aabb is soeren
17:02:05 [Zakim]
+soeren; got it
17:02:07 [cygri]
cygri has joined #rdb2rdf
17:02:11 [mhausenblas]
Zakim, who's here?
17:02:11 [Zakim]
On the phone I see ??P10, ??P15, +1.512.471.aaaa, whalb, ??P24, mhausenblas, hhalpin, soeren
17:02:13 [Zakim]
On IRC I see cygri, soeren, nunolopes, Marcelo, Souri, Zakim, RRSAgent, li_ma, Ahmed, Seema, whalb, juansequeda, mhausenblas, hhalpin, MacTed, iv_an_ru, trackbot, ericP
17:02:21 [mhausenblas]
cygri is with mhausenblas
17:02:34 [mhausenblas]
Zakim, cygri is with mhausenblas
17:02:35 [Zakim]
+cygri; got it
17:02:53 [mhausenblas]
RRSAgent, draft minutes
17:02:53 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/01/26-RDB2RDF-minutes.html mhausenblas
17:03:05 [Zakim]
+??P38
17:03:11 [mhausenblas]
zakim, make logs public
17:03:11 [Zakim]
I don't understand 'make logs public', mhausenblas
17:03:17 [hhalpin]
Zakim, ??P38 is hhalpin
17:03:17 [Zakim]
+hhalpin; got it
17:03:23 [mhausenblas]
RRSAgent, make logs public
17:03:55 [Zakim]
+ +035385271aacc
17:04:15 [mhausenblas]
Zakim, aacc is nunolopes
17:04:15 [Zakim]
+nunolopes; got it
17:04:44 [Zakim]
+OpenLink_Software
17:05:05 [MacTed]
Zakim, OpenLink_Software is temporarily me
17:05:05 [Zakim]
+MacTed; got it
17:05:08 [MacTed]
Zakim, mute me
17:05:08 [Zakim]
MacTed should now be muted
17:05:39 [mhausenblas]
regrets+ Angela
17:06:05 [whalb]
topic: roll call
17:06:21 [mhausenblas]
regrets+ Ben
17:06:59 [whalb]
topic: approve minutes
17:07:14 [whalb]
http://www.w3.org/2010/01/19-RDB2RDF-minutes.html
17:07:17 [mhausenblas]
+1
17:07:18 [Ahmed]
+1
17:07:28 [mhausenblas]
ACTION-18?
17:07:28 [trackbot]
ACTION-18 -- Harry Halpin to update web-page and schedule -- due 2010-01-19 -- OPEN
17:07:28 [trackbot]
http://www.w3.org/2001/sw/rdb2rdf/track/actions/18
17:07:33 [mhausenblas]
close ACTION-18
17:07:33 [trackbot]
ACTION-18 Update web-page and schedule closed
17:07:40 [mhausenblas]
ACTION-19?
17:07:40 [trackbot]
ACTION-19 -- Harry Halpin to put Souri's draft into a WBS poll and notify the WG -- due 2010-01-19 -- OPEN
17:07:40 [trackbot]
http://www.w3.org/2001/sw/rdb2rdf/track/actions/19
17:07:43 [Zakim]
+??P5
17:08:10 [hhalpin]
will ping souri re e-mail.
17:08:21 [hhalpin]
which part of the draft in particular?
17:08:26 [Souri]
We have put a write-up (including an XML syntax) on the wiki
17:08:27 [hhalpin]
send me the URI
17:08:32 [hhalpin]
(looking)
17:08:42 [Souri]
under Working docs
17:09:26 [mhausenblas]
ACTION-20?
17:09:26 [trackbot]
ACTION-20 -- Eric Prud'hommeaux to update http://www.w3.org/2001/sw/rdb2rdf/wiki/LinkedDataAspects#Linked_Data_Principles to say 'MUST allow to..." -- due 2010-01-26 -- OPEN
17:09:26 [trackbot]
http://www.w3.org/2001/sw/rdb2rdf/track/actions/20
17:09:36 [mhausenblas]
close ACTION-20
17:09:36 [trackbot]
ACTION-20 Update http://www.w3.org/2001/sw/rdb2rdf/wiki/LinkedDataAspects#Linked_Data_Principles to say 'MUST allow to..." closed
17:09:44 [mhausenblas]
ACTION-21
17:09:50 [mhausenblas]
close ACTION-21
17:09:50 [trackbot]
ACTION-21 Update http://www.w3.org/2001/sw/rdb2rdf/wiki/LinkedDataAspects#Well-known_Entities to reflect discussion (3 cases) closed
17:09:58 [mhausenblas]
ACTION-22?
17:09:58 [trackbot]
ACTION-22 -- Eric Prud'hommeaux to add Ahmed's plan to the Wiki -- due 2010-01-26 -- OPEN
17:09:58 [trackbot]
http://www.w3.org/2001/sw/rdb2rdf/track/actions/22
17:10:06 [mhausenblas]
close ACTION-22
17:10:08 [trackbot]
ACTION-22 Add Ahmed's plan to the Wiki closed
17:10:15 [mhausenblas]
ACTION-23
17:10:17 [mhausenblas]
ACTION-23?
17:10:17 [trackbot]
ACTION-23 -- Richard Cyganiak to update http://www.w3.org/2001/sw/rdb2rdf/wiki/LinkedDataAspects#Provenance re today's discussion -- due 2010-01-26 -- OPEN
17:10:17 [trackbot]
http://www.w3.org/2001/sw/rdb2rdf/track/actions/23
17:10:18 [Seema]
Souri I will follow up with you on this
17:11:19 [whalb]
ahmed: main topic is how we continue forward, give an outline and set direction
17:12:02 [hhalpin]
sounds good to me
17:12:11 [whalb]
topic: R2RML Mapping aspects
17:12:26 [mhausenblas]
RRSAgent, draft minutes
17:12:26 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/01/26-RDB2RDF-minutes.html mhausenblas
17:12:33 [whalb]
ahmed: two sub-teams, another team for linked data needed
17:12:42 [hhalpin]
well, sort of.
17:12:47 [hhalpin]
q+
17:12:59 [whalb]
soeren: no further linked data group needed, included in both other sub-teams
17:13:24 [whalb]
ahmed: wants linked data area to be covered anyway
17:13:41 [whalb]
... need more people commited to sub-teams
17:14:00 [whalb]
... how are we going to proceed?
17:14:03 [hhalpin]
+1 status reports
17:14:06 [Souri]
This was the URL: http://www.w3.org/2001/sw/rdb2rdf/wiki/RDB-to-RDF_mapping:_A_SQL-based_Approach
17:14:18 [whalb]
... are teams going to give status reports of e.g. 15mins?
17:14:25 [whalb]
... how are we going to show progress?
17:14:30 [mhausenblas]
ack hhalpin
17:15:46 [hhalpin]
http://neurocommons.org/page/Common_Naming_Project
17:15:54 [hhalpin]
http://www.okkam.org/
17:16:02 [hhalpin]
http://linkeddata.org/
17:16:27 [whalb]
hhalpin: suggest that each group has a member dealing with the different aspects of linked data, etc.
17:17:02 [hhalpin]
i'd also suggest that we have a session with the HCLS group
17:17:06 [whalb]
mhausenblas: we should focus on mapping stuff in the first phase, other members supporting both teams re. linked data
17:17:20 [hhalpin]
as they have interaction for NeuroCommons Common Naming Project
17:17:54 [whalb]
... whenever there is a need from one of the groups to get some input on linked data topics the experts should chime in
17:18:12 [hhalpin]
ericP?
17:18:20 [hhalpin]
He's the staff contact for HCLS
17:18:27 [whalb]
hhalpin: also input from the life science domain, probalby from ericp
17:19:19 [mhausenblas]
ACTION: ericP to take care of the HCLS statement
17:19:19 [trackbot]
Sorry, couldn't find user - ericP
17:19:36 [hhalpin]
hmm
17:19:38 [hhalpin]
let me look
17:20:29 [Zakim]
+EricP
17:20:31 [whalb]
soeren: two proposals: oracle created one and soeren tried to distill another one, wanted to align efforts
17:20:44 [whalb]
... not yet talked to each of the other groups
17:21:08 [whalb]
... suggestions for possible syntax of the mapping:
17:21:15 [soeren]
http://www.w3.org/2001/sw/rdb2rdf/wiki/R2RML_SQL_View_Annotation
17:21:38 [whalb]
... called SQL View Annotation, intention is to add syntax for mapping language
17:22:54 [whalb]
... syntax: db conn needs to be established, namespaces + prefixes
17:23:16 [whalb]
... two distinguished namespaces: base namespace for creating data instance items
17:23:26 [whalb]
... optional schema namespace: properties, classes
17:23:47 [whalb]
... could be overwritten by custom definitions
17:24:07 [whalb]
... table definition is the core, most important part
17:24:49 [whalb]
... R2RMap current single syntactical element, first parameter basically a relation identifier
17:25:07 [whalb]
... second element: path used to create linked data entity identifiers
17:25:20 [whalb]
... additional parameters are optional
17:25:50 [whalb]
... third element: reference to a class (rdfs, owl) used to make instances of this specific clas (optional parameter)
17:26:19 [whalb]
... remaining parameters: definitions for each of the columns in the relation (from param1)
17:26:45 [whalb]
... they are all optional
17:27:02 [whalb]
... if omitted the column name is used for creating identifiers
17:27:24 [whalb]
... syntax is inspired by triplify
17:27:50 [mhausenblas]
q+ to note on Test Cases
17:28:19 [whalb]
... additional issues: user defined output processing functions, static metadata, attribute-value tables, named graphs,
17:28:46 [whalb]
... update logs, provenance (triplify approach could also be applied here)
17:29:07 [whalb]
... a lot of work already done on how to tackle these issues
17:29:35 [whalb]
... core is r2rmap syntax
17:29:48 [whalb]
... as a staring point that can be refined later on
17:30:20 [mhausenblas]
ack me
17:30:20 [Zakim]
mhausenblas, you wanted to note on Test Cases
17:30:22 [whalb]
mhausenblas: start thinking about test cases: specify sample input and output
17:31:03 [whalb]
... ideally a set of test cases is created/made available
17:31:39 [whalb]
ahmed: alignment with ashok?
17:32:06 [whalb]
soeren: contacted ashok/oracle, waiting for responses
17:32:53 [whalb]
... discussion will take 2-3 more weeks
17:33:19 [mhausenblas]
RRSAgent, draft minutes
17:33:19 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/01/26-RDB2RDF-minutes.html mhausenblas
17:33:21 [Souri]
Soren, not sure if you got our email from Friday -- we wanted to find out times that would be convenient to you
17:33:26 [whalb]
ahmed: two teams working together, is there a need for a leader of the sub-teams?
17:33:39 [whalb]
... responsible for communication, coordination, not a technical leader
17:34:13 [whalb]
mhausenblas: person in charge should also have reporting responsibility
17:35:01 [whalb]
ahmed: any volunteers or suggestions?
17:35:49 [whalb]
orri: we should do something that substantially relies on sql
17:36:49 [whalb]
... fine with something that's compatible to sql views as long as it works out in the end
17:37:51 [Souri]
Did anyone get a chance to review the XML syntax we had posted last week? (special case simplification with auto-mapping is always possible)
17:38:47 [hhalpin]
q+
17:39:21 [hhalpin]
Zakim, who's making noise?
17:39:31 [Zakim]
hhalpin, listening for 10 seconds I heard sound from the following: ??P15 (9%), soeren (14%)
17:39:48 [hhalpin]
For soundness and completeness, I would defer to Marcelo or at least have him go over the draft :)
17:40:50 [Marcelo]
sure, I can do it :-)
17:43:03 [hhalpin]
ericP: I think it's left stuff to specify mapping SPARQL to SQL
17:43:13 [mhausenblas]
scribenick: hhalpin
17:43:19 [hhalpin]
soeren: but SPARQL constructs are very limited in expressivity
17:43:36 [hhalpin]
soeren: assigning results of a computation to a new variable
17:43:44 [hhalpin]
soeren: build a string by concating 2 others
17:43:56 [hhalpin]
soeren: i.e. firstname+lastname concat for a URI
17:44:01 [soeren]
hhalpin, its richard
17:44:01 [hhalpin]
ericP: can't do that.
17:44:14 [hhalpin]
s/soeren/cygri
17:44:25 [hhalpin]
cygri: And we are not sure about SPARQL 1.1
17:44:50 [hhalpin]
... we will have use-cases outside of SPARQL construct
17:44:58 [hhalpin]
... this will require a bit of work
17:45:04 [hhalpin]
... if it is possible
17:45:08 [hhalpin]
ericP: understood
17:45:31 [hhalpin]
orri: it would seem to me
17:45:44 [hhalpin]
... that we need to things in sql
17:45:48 [[1]whalb]
[1]whalb has joined #RDB2RDF
17:45:53 [hhalpin]
... but we should take sparql 1.1 as a given
17:46:09 [hhalpin]
ericP: but the point remains
17:46:10 [[1]whalb]
* sorry, got disconnected
17:46:12 [hhalpin]
... that a bit of sql
17:46:23 [hhalpin]
... the commonality is still more expressive than even sparql 1.1
17:46:35 [hhalpin]
... what do we save about this use-cases?
17:46:50 [hhalpin]
Ahmed: the main issue with SQL view
17:46:59 [hhalpin]
... is you have to "touch" the database
17:47:03 [whalb]
soeren: disagrees
17:47:14 [whalb]
... no need to touch the database
17:47:17 [Souri]
I disagree
17:47:29 [whalb]
cygri: several database problems with horrible performance
17:48:01 [Souri]
agree with Soren
17:48:10 [whalb]
soeren: customised mapping approach still could be done, optimised subqueries will be faster
17:48:19 [whalb]
orri: sql dbs will be fine
17:48:48 [whalb]
... query gets unusual when mapping sparql to sql
17:48:54 [whalb]
... in prinicple should be fine
17:49:35 [mhausenblas]
scribenick: whalb
17:49:51 [whalb]
cygri: sparql to sql translation is hard for the user to optimise
17:51:03 [whalb]
?: manipulation can be done on internal representations
17:51:29 [whalb]
cygri: you can use base tables if that is all you need
17:51:38 [juansequeda]
yes
17:51:40 [MacTed]
Zakim, who's making noise?
17:51:47 [mhausenblas]
s/?:/Dan:
17:51:51 [Zakim]
MacTed, listening for 10 seconds I heard sound from the following: mhausenblas (100%), soeren (43%)
17:52:07 [whalb]
... need to rely on optimiser in database if complex query
17:52:27 [whalb]
... not same effort as doing optimisation on other side
17:52:48 [whalb]
ahmed: subqueries not a problem
17:53:07 [whalb]
... problem is at the end you get sql datatypes
17:53:25 [whalb]
cygri: not a problem, soeren's syntax proposal covers that basically
17:53:54 [whalb]
... can be easily done outside db
17:54:17 [whalb]
ahmed: why classify this approach as sql view
17:54:34 [whalb]
... translating sql data outside the db
17:54:51 [whalb]
soeren: there is need for a mapping engine finally
17:55:03 [whalb]
... sql (view) annotation approach
17:55:17 [whalb]
... sql engine already does mapping from sql data to data
17:55:35 [whalb]
ahmed: disagrees, you get back sql datatypes if mapping is done outside
17:55:45 [whalb]
... why call this approach sql view mapping
17:56:25 [whalb]
cygri: sql output is turned into rdf triples
17:56:38 [whalb]
... transforming to sql view is done inside db
17:57:00 [ericP]
-> http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2010Jan/att-0050/RDB2RDFTest.scala SPARQL queries tranlated to SQL
17:57:07 [Souri]
The SQLdefString is the one that is employed directly against the host db (i.e., the data source)
17:57:11 [whalb]
... transformation from three col sql result is simple work done outside
17:57:19 [whalb]
... mapping is inside the db
17:57:49 [whalb]
ahmed: view is defined term in sql world
17:58:09 [whalb]
... would not call that approach sql view, misuse of terminology
17:58:18 [hhalpin]
We can call it something else I imagine...
17:59:01 [whalb]
orri: column is the predicate on the row, multi-col views ok
17:59:41 [whalb]
ahmed: sql view means that data is updated automatically
17:59:53 [sdas2]
sdas2 has joined #rdb2rdf
18:00:02 [Zakim]
-??P5
18:00:36 [whalb]
... the last mentioned approach does not need any special optimisation
18:00:38 [sdas2]
sdas2 has joined #rdb2rdf
18:01:11 [whalb]
cygri: still a problem for specific db systems, e.g. mysql
18:01:35 [whalb]
... simple looking queries can perform poorly
18:01:46 [mhausenblas]
we need to wrap up soon, we're on the top of the hour
18:02:05 [whalb]
ahmed: which subqueries do not perfom well?
18:02:28 [whalb]
... mysql usually only has drawbacks in transactions, updates, ...
18:02:36 [whalb]
... difference if change in db is needed or not
18:02:41 [whalb]
... we need to support both cases
18:03:17 [Seema]
Oracle presentation covers both "db" and "no db" cases
18:03:18 [hhalpin]
hmmm...
18:03:40 [Souri]
Souri has joined #rdb2rdf
18:03:49 [whalb]
... interested to get to know difficult subqueries for mysql
18:04:19 [whalb]
soeren: question seems not to be important
18:04:27 [whalb]
... there are some issues with every db
18:04:40 [ericP]
http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2010Jan/att-0050/RDB2RDFTest.scala
18:04:43 [whalb]
... but there has been spent a lot of time on db development
18:05:12 [whalb]
ericp: interested if those sql queries could make troubles
18:05:29 [hhalpin]
i think we can continue for a bit till discussion ends
18:05:39 [whalb]
ahmed: subquery is no issue at any level
18:05:55 [whalb]
... problem is the optimiser for specific types of queries
18:05:55 [mhausenblas]
I'd love to see a write-up of today's discussion :)
18:08:06 [whalb]
ahmed: create a list of typical queries generated from sparql to sql to figure out the difficult ones
18:08:12 [mhausenblas]
Michael: I like today's discussion - eventually we start to disagree
18:09:55 [whalb]
... start collecting cases on the wiki
18:10:24 [whalb]
ericp: sql generated from rdb2rdf translations, sql that is a "show stopper"
18:11:00 [whalb]
ahmed: would like to see an approach that does not touch the db
18:11:01 [ericP]
GeneratedSQL and PotentialSQLIssues
18:11:04 [mhausenblas]
thanks to ericP for kicking-off the Wiki stuff
18:11:32 [mhausenblas]
RRSAgent, draft minutes
18:11:32 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/01/26-RDB2RDF-minutes.html mhausenblas
18:11:37 [whalb]
souri: oracle presentation mentioned that in the case db is not touched
18:12:01 [mhausenblas]
Zakim, list attendees
18:12:01 [Zakim]
As of this point the attendees have been +1.512.471.aaaa, whalb, mhausenblas, hhalpin, +49.322.222.0.aabb, soeren, cygri, +035385271aacc, nunolopes, MacTed, EricP
18:12:04 [Zakim]
-soeren
18:12:04 [Zakim]
-??P10
18:12:05 [Zakim]
-EricP
18:12:05 [Zakim]
-hhalpin
18:12:07 [Zakim]
-whalb
18:12:07 [Zakim]
-MacTed
18:12:08 [Zakim]
-??P15
18:12:09 [Zakim]
-??P24
18:12:27 [Zakim]
-hhalpin.a
18:12:28 [Ahmed]
Bye.
18:12:29 [Zakim]
-mhausenblas
18:12:31 [hhalpin]
bye
18:12:31 [Zakim]
- +1.512.471.aaaa
18:12:35 [mhausenblas]
adjourned
18:12:42 [mhausenblas]
RRSAgent, draft minutes
18:12:42 [RRSAgent]
I have made the request to generate http://www.w3.org/2010/01/26-RDB2RDF-minutes.html mhausenblas
18:12:59 [Zakim]
-nunolopes
18:13:01 [Zakim]
SW_RDB2RDF()12:00PM has ended
18:13:02 [Zakim]
Attendees were +1.512.471.aaaa, whalb, mhausenblas, hhalpin, +49.322.222.0.aabb, soeren, cygri, +035385271aacc, nunolopes, MacTed, EricP
18:19:41 [cygri]
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