SPARQL Entailment Regimes

Minutes of 24 February 2010

Agenda
http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24
Seen
Axel Polleres, Birte Glimm, Chimezie Ogbuji, Ivan Herman, Sandro Hawke
Chair
Birte Glimm
Scribe
Axel Polleres
IRC Log
Original and Editable Wiki Version
Resolutions

None.

Topics
<sandro> Meeting: SPARQL Entailment Regimes
<sandro> chair: bglimm
<sandro> scribe: Axel

(Scribe set to Axel Polleres)

15:02:38 <RRSAgent> logging to http://www.w3.org/2010/02/24-sparql-ent-irc

RRSAgent IRC Bot: logging to http://www.w3.org/2010/02/24-sparql-ent-irc

15:02:51 <bglimm> agenda: http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24
17:46:03 <bglimm> Hi Ivan

(No events recorded for 163 minutes)

Birte Glimm: Hi Ivan

17:46:10 <ivan> hi birte

Ivan Herman: hi birte

17:46:21 <bglimm> can we set the link to the agenda as chat topic?

Birte Glimm: can we set the link to the agenda as chat topic?

17:46:29 <bglimm> http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

Birte Glimm: http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

17:46:32 <ivan> of course

Ivan Herman: of course

17:46:35 <bglimm> I didn't manage to do that

Birte Glimm: I didn't manage to do that

17:46:45 <ivan> ivan has changed the topic to: http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

Ivan Herman: ivan has changed the topic to: http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

17:46:54 <bglimm> :-)

Birte Glimm: :-)

17:46:55 <ivan> ivan has changed the topic to: agenda: http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

Ivan Herman: ivan has changed the topic to: agenda: http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

17:47:32 <ivan> zakim, room for 10 for 90 minutes?

Ivan Herman: zakim, room for 10 for 90 minutes?

17:47:33 <Zakim> ok, ivan; conference Team_(sparql-ent)17:47Z scheduled with code 26631 (CONF1) for 90 minutes until 1917Z

Zakim IRC Bot: ok, ivan; conference Team_(sparql-ent)17:47Z scheduled with code 26631 (CONF1) for 90 minutes until 1917Z

17:47:44 <ivan> here we are:-)

Ivan Herman: here we are:-)

17:47:58 <ivan> I asked for 90 minutes if we round out (and we still have 10 minutes)

Ivan Herman: I asked for 90 minutes if we round out (and we still have 10 minutes)

17:48:44 <ivan> ivan has changed the topic to: Zakim code 26631, agenda http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

Ivan Herman: ivan has changed the topic to: Zakim code 26631, agenda http://www.w3.org/2009/sparql/wiki/Agenda-2010-02-24

17:49:19 <bglimm> :-)

Birte Glimm: :-)

17:50:32 <bglimm> I've updated the wiki agenda now

Birte Glimm: I've updated the wiki agenda now

17:58:37 <Zakim> Team_(sparql-ent)17:47Z has now started

(No events recorded for 8 minutes)

Zakim IRC Bot: Team_(sparql-ent)17:47Z has now started

17:58:44 <Zakim> +bglimm

Zakim IRC Bot: +bglimm

17:58:53 <AxelPolleres> hi all

hi all

17:58:57 <bglimm> Hi

Birte Glimm: Hi

17:59:01 <bglimm> The access code is 26631

Birte Glimm: The access code is 26631

17:59:02 <AxelPolleres> chime?

chime?

17:59:07 <bglimm> Not yet

Birte Glimm: Not yet

18:01:44 <AxelPolleres> will sandro join?

will sandro join?

18:01:52 <bglimm> He said so I think

Birte Glimm: He said so I think

18:01:55 <ivan> zakim, dial ivan-voip

Ivan Herman: zakim, dial ivan-voip

18:01:55 <Zakim> ok, ivan; the call is being made

Zakim IRC Bot: ok, ivan; the call is being made

18:01:57 <Zakim> +Ivan

Zakim IRC Bot: +Ivan

18:02:41 <Zakim> +AxelPolleres

Zakim IRC Bot: +AxelPolleres

18:03:48 <sandro> zakim, what is the code?

Sandro Hawke: zakim, what is the code?

18:03:48 <Zakim> the conference code is 26631 (tel:+1.617.761.6200 tel:+33.4.89.06.34.99 tel:+44.117.370.6152), sandro

Zakim IRC Bot: the conference code is 26631 (tel:+1.617.761.6200 tel:+33.4.89.06.34.99 tel:+44.117.370.6152), sandro

18:03:51 <sandro> rrsagent, pointer?

Sandro Hawke: rrsagent, pointer?

18:03:51 <RRSAgent> See http://www.w3.org/2010/02/24-sparql-ent-irc#T18-03-51

RRSAgent IRC Bot: See http://www.w3.org/2010/02/24-sparql-ent-irc#T18-03-51

18:04:11 <Zakim> +Sandro

Zakim IRC Bot: +Sandro

18:04:15 <sandro> zakim, who is on the call?

Sandro Hawke: zakim, who is on the call?

18:04:15 <Zakim> On the phone I see bglimm, Ivan, AxelPolleres, Sandro

Zakim IRC Bot: On the phone I see bglimm, Ivan, AxelPolleres, Sandro

18:05:33 <sandro> (axel to make sure anything important gets recorded, but not really scribe.)

Sandro Hawke: (axel to make sure anything important gets recorded, but not really scribe.)

18:05:50 <AxelPolleres> inconsistency handling is not clear

inconsistency handling is not clear

18:06:55 <AxelPolleres> sandro: at least, is there a protocol way to signal inconsistency, even if not required

Sandro Hawke: at least, is there a protocol way to signal inconsistency, even if not required

18:07:03 <AxelPolleres> ... seems to me that we want to have that

... seems to me that we want to have that

18:08:13 <ivan> q+

Ivan Herman: q+

18:10:13 <AxelPolleres> birte can you paste the C2 variation again?

birte can you paste the C2 variation again?

18:10:28 <Zakim> + +1.216.445.aaaa

Zakim IRC Bot: + +1.216.445.aaaa

18:10:31 <bglimm> Wait a sec

Birte Glimm: Wait a sec

18:10:35 <AxelPolleres> guess that's chime?

guess that's chime?

18:10:42 <chimezie> Zakim +1.216.445.aaaa is me

Chimezie Ogbuji: Zakim +1.216.445.aaaa is me

18:10:44 <chimezie> yes :)

Chimezie Ogbuji: yes :)

18:10:47 <bglimm>     Current C2 in PWD:

Birte Glimm: Current C2 in PWD:

18:10:47 <bglimm>     (C2) Each variable x that occurs in the subject position of a triple in

Birte Glimm: (C2) Each variable x that occurs in the subject position of a triple in

18:10:47 <bglimm>          BGP is such that sk(μ(x)) occurs in sk(SG).

Birte Glimm: BGP is such that sk(μ(x)) occurs in sk(SG).

18:10:48 <bglimm>     Proposed C2:

Birte Glimm: Proposed C2:

18:10:48 <bglimm>     (C2) For each variable x in V(BGP), sk(μ(x)) occurs in sk(SG) or in

Birte Glimm: (C2) For each variable x in V(BGP), sk(μ(x)) occurs in sk(SG) or in

18:10:48 <bglimm>          Vocab.

Birte Glimm: Vocab.

18:12:16 <AxelPolleres>  rdf:_1 .... rdf:_n ?

rdf:_1 .... rdf:_n ?

18:13:28 <AxelPolleres> Vocab is a meant here to be a finite subset of the RDF, RDFS, OWL vocabularies

Vocab is a meant here to be a finite subset of the RDF, RDFS, OWL vocabularies

18:13:34 <bglimm>  Here vocal is defined as the reserved vocabulary for the entailment

Birte Glimm: Here vocal is defined as the reserved vocabulary for the entailment

18:13:34 <bglimm>     regime (e.g., the RDF vocabulary for RDF entailment) minus terms of the

Birte Glimm: regime (e.g., the RDF vocabulary for RDF entailment) minus terms of the

18:13:34 <bglimm>     form rdf:_n with n in {1, 2, …}.

Birte Glimm: form rdf:_n with n in {1, 2, …}.

18:15:24 <AxelPolleres> this condition is not about inconsistencies, is it?

this condition is not about inconsistencies, is it?

18:15:49 <AxelPolleres> ivan: we don't want to restrict, where we don't have to.

Ivan Herman: we don't want to restrict, where we don't have to.

18:17:51 <AxelPolleres> my problem is ... we cannot reach the infinite wisdom... anyways

my problem is ... we cannot reach the infinite wisdom... anyways

18:21:17 <AxelPolleres> if we want to keep answers finite... we have to drop intuitiveness at some point :-(

if we want to keep answers finite... we have to drop intuitiveness at some point :-(

18:24:00 <AxelPolleres> still la bit puzzled about the role of data values in C2

still la bit puzzled about the role of data values in C2

18:24:29 <AxelPolleres> take the decision on C2 on email...

take the decision on C2 on email...

18:25:25 <AxelPolleres> birte to please explain the role of data values in C2

birte to please explain the role of data values in C2

18:26:25 <AxelPolleres> ivan: rif not being rrec shouldn't be a problem, confident that it will be ready there, afraid that it would be interpreted in underied way, if we mark it

Ivan Herman: rif not being rrec shouldn't be a problem, confident that it will be ready there, afraid that it would be interpreted in underied way, if we mark it

18:26:31 <AxelPolleres> birte: ok

Birte Glimm: ok

18:31:08 <AxelPolleres> I think we can define SPARQL wrt a RIF/RDF combination... but not really how you get to the scoping graph?

I think we can define SPARQL wrt a RIF/RDF combination... but not really how you get to the scoping graph?

18:31:32 <AxelPolleres> we can just say what the scoping grpah for some RIF/RDF combination is

we can just say what the scoping grpah for some RIF/RDF combination is

18:33:27 <AxelPolleres> we can sort out how we get to the correspondoing RIF/RDF combination later on.

we can sort out how we get to the correspondoing RIF/RDF combination later on.

18:34:07 <ivan> q+

Ivan Herman: q+

18:34:25 <AxelPolleres> birte: at some point it was discussed whether we'd have an entailment regime per ruleset.

Birte Glimm: at some point it was discussed whether we'd have an entailment regime per ruleset.

18:34:28 <AxelPolleres> q+

q+

18:34:34 <ivan> ack ivan

Ivan Herman: ack ivan

18:34:42 <AxelPolleres> ivan thinks that this is useless..

ivan thinks that this is useless..

18:34:59 <bglimm>  Here's somebody from RIF suggestion that: http://lists.w3.org/Archives/Public/public-rif-wg/2010Jan/0019.html

Birte Glimm: Here's somebody from RIF suggestion that: http://lists.w3.org/Archives/Public/public-rif-wg/2010Jan/0019.html

18:35:05 <AxelPolleres> q+ to state that this point is void, if we have solved "rif:imports"

q+ to state that this point is void, if we have solved "rif:imports"

18:35:18 <AxelPolleres> ack AxelPolleres

ack AxelPolleres

18:35:18 <Zakim> AxelPolleres, you wanted to state that this point is void, if we have solved "rif:imports"

Zakim IRC Bot: AxelPolleres, you wanted to state that this point is void, if we have solved "rif:imports"

18:36:43 <AxelPolleres> sandro: the case that is still open is...

Sandro Hawke: the case that is still open is...

18:37:09 <AxelPolleres> ... how does the client state which ruleset?

... how does the client state which ruleset?

18:37:27 <AxelPolleres> FROM mygraph ...

FROM mygraph ...

18:37:36 <AxelPolleres> where mygraph refers to a ruleset

where mygraph refers to a ruleset

18:38:05 <sandro> don't we need:   QUERY ... FROM ... WITH <entailment-regime or ruleset > ....

Sandro Hawke: don't we need: QUERY ... FROM ... WITH <entailment-regime or ruleset > ....

18:39:04 <sandro> ahhhh,   FROM <ruleset>

Sandro Hawke: ahhhh, FROM <ruleset>

18:39:55 <bglimm> Select ... FROM data.rdf FROM rules.rdf WHERE { ... }

Birte Glimm: Select ... FROM data.rdf FROM rules.rdf WHERE { ... }

18:40:22 <sandro> so this needs RIF-in-RDF for FROM.

Sandro Hawke: so this needs RIF-in-RDF for FROM.

18:41:01 <sandro> ivan:  the rules.rdf would be an rdf graph with the rif:import triple in it.

Ivan Herman: the rules.rdf would be an rdf graph with the rif:import triple in it. [ Scribe Assist by Sandro Hawke ]

18:41:10 <AxelPolleres> the current definitions (if we don't want to interfer with SPARQL 1.0 ) we can't do FROM <ruleset>

the current definitions (if we don't want to interfer with SPARQL 1.0 ) we can't do FROM <ruleset>

18:41:16 <bglimm> yes that would work

Birte Glimm: yes that would work

18:41:34 <AxelPolleres> ... but we can do FROM <... rif:imports  ...>

... but we can do FROM <... rif:imports ...>

18:42:49 <bglimm> it should probably called rif:useRuleSet or something like that

Birte Glimm: it should probably called rif:useRuleSet or something like that

18:43:04 <bglimm> or even sparql:useRuleSet

Birte Glimm: or even sparql:useRuleSet

18:44:08 <AxelPolleres>  sparql:useRuleSet

sparql:useRuleSet

18:44:51 <sandro>  conclusion: if necessary, we can do rif-import under spaql

Sandro Hawke: conclusion: if necessary, we can do rif-import under spaql

18:45:01 <AxelPolleres> conclusion is... if all goes wrong, we can do� "rif:imports" ourselves.

conclusion is... if all goes wrong, we can do� "rif:imports" ourselves.

18:45:57 <AxelPolleres> I think we can handle bnodes.

I think we can handle bnodes.

18:46:24 <AxelPolleres> chime suggested to stick with *strongly safe* core?

chime suggested to stick with *strongly safe* core?

18:47:30 <bglimm> if p(?n) then p(?n+1).

Birte Glimm: if p(?n) then p(?n+1).

18:47:30 <bglimm> p(1).

Birte Glimm: p(1).

18:47:31 <bglimm> and the query

Birte Glimm: and the query

18:47:31 <bglimm> p(?x).

Birte Glimm: p(?x).

18:51:01 <AxelPolleres> sandro: why the finiteness restriction in first place?

Sandro Hawke: why the finiteness restriction in first place?

18:51:05 <AxelPolleres> can we change that?

can we change that?

18:51:42 <AxelPolleres> ... no implementation crucially relies on that.

... no implementation crucially relies on that.

18:52:17 <AxelPolleres> ...if it's just not intuitive, we may want to question that.

...if it's just not intuitive, we may want to question that.

18:53:19 <sandro> axel: simple way to restrict finiteness:    things in answer must occur in data.

Axel Polleres: simple way to restrict finiteness: things in answer must occur in data. [ Scribe Assist by Sandro Hawke ]

18:55:38 <sandro> sandro: that's a non starter -- you couldn't get results from a computation.

Sandro Hawke: that's a non starter -- you couldn't get results from a computation. [ Scribe Assist by Sandro Hawke ]

18:56:07 <sandro> axel: you could allow computations to recursive level N from the data.

Axel Polleres: you could allow computations to recursive level N from the data. [ Scribe Assist by Sandro Hawke ]

18:57:03 <sandro> sandro: just say it has to be any finite number of recursions.

Sandro Hawke: just say it has to be any finite number of recursions. [ Scribe Assist by Sandro Hawke ]

18:57:11 <AxelPolleres> sandro: how if we only restrict that any implemnentation has to limit the recursion depth.

Sandro Hawke: how if we only restrict that any implemnentation has to limit the recursion depth.

18:57:16 <AxelPolleres> ... but not how?

... but not how?

18:58:42 <AxelPolleres> p(1)

p(1)

18:58:56 <AxelPolleres> q(x+1) :- p(x).

q(x+1) :- p(x).

18:59:10 <AxelPolleres> r(x+1) :- q(x)

r(x+1) :- q(x)

19:05:43 <AxelPolleres> sandro: suggests... just leave behaivor of SPARQL undefined whenever the closure of R is infinite?

(No events recorded for 6 minutes)

Sandro Hawke: suggests... just leave behaivor of SPARQL undefined whenever the closure of R is infinite?

19:07:23 <AxelPolleres> chime: suggest to standardise a possibly boring finite subset

Chimezie Ogbuji: suggest to standardise a possibly boring finite subset

19:07:35 <AxelPolleres> sandr: suggest to just don't worry about finiteness

Sandro Hawke: suggest to just don't worry about finiteness

19:07:43 <AxelPolleres> (two quite opposite positions)

(two quite opposite positions)

19:09:16 <sandro> sandro: use case, define an odd() predicate, then query for { ?s ?p ?o; ?o a oddNumber }

Sandro Hawke: use case, define an odd() predicate, then query for { ?s ?p ?o; ?o a oddNumber } [ Scribe Assist by Sandro Hawke ]

19:09:41 <Zakim> -bglimm

Zakim IRC Bot: -bglimm

19:09:52 <bglimm> sorry dropped out

Birte Glimm: sorry dropped out

19:11:33 <Zakim> +bglimm

Zakim IRC Bot: +bglimm

19:11:48 <ivan> q+

Ivan Herman: q+

19:12:06 <AxelPolleres> ivan is still on the q

ivan is still on the q

19:12:50 <sandro> axel: a use case for RIF in SPARQL with strongly-safe core == subsets of RDFS-entailment, ad hoc OWL-RL entailment.

Axel Polleres: a use case for RIF in SPARQL with strongly-safe core == subsets of RDFS-entailment, ad hoc OWL-RL entailment. [ Scribe Assist by Sandro Hawke ]

19:13:46 <AxelPolleres> ivan: what comes to my mind... did we have in SPARQL a way to include a time/resource limit?

Ivan Herman: what comes to my mind... did we have in SPARQL a way to include a time/resource limit?

19:14:01 <AxelPolleres> sandro: we only have result limit

Sandro Hawke: we only have result limit

19:14:08 <sandro> sandro: I think it only has LIMIT; with entailment, yes, it would be nice to have TIME limit, too.

Sandro Hawke: I think it only has LIMIT; with entailment, yes, it would be nice to have TIME limit, too. [ Scribe Assist by Sandro Hawke ]

19:14:08 <bglimm> resource limit: LIMIT N

Birte Glimm: resource limit: LIMIT N

19:15:03 <AxelPolleres> not for this round, I guess.

not for this round, I guess.

19:15:50 <sandro> sandro: maybe you can throw this in the SPARQL protocol, as an ignore-if-you-don't-understand

Sandro Hawke: maybe you can throw this in the SPARQL protocol, as an ignore-if-you-don't-understand [ Scribe Assist by Sandro Hawke ]

19:16:32 <Zakim> -Ivan

Zakim IRC Bot: -Ivan

19:16:32 <bglimm> bye

Birte Glimm: bye

19:16:33 <Zakim> - +1.216.445.aaaa

Zakim IRC Bot: - +1.216.445.aaaa

19:16:33 <AxelPolleres> thanks birte...

thanks birte...

19:16:35 <Zakim> -Sandro

Zakim IRC Bot: -Sandro

19:16:35 <bglimm> adjourned

Birte Glimm: adjourned

19:16:46 <Zakim> -bglimm

Zakim IRC Bot: -bglimm

19:16:48 <Zakim> -AxelPolleres

Zakim IRC Bot: -AxelPolleres

19:16:49 <Zakim> Team_(sparql-ent)17:47Z has ended

Zakim IRC Bot: Team_(sparql-ent)17:47Z has ended

19:16:51 <Zakim> Attendees were bglimm, Ivan, AxelPolleres, Sandro, +1.216.445.aaaa

Zakim IRC Bot: Attendees were bglimm, Ivan, AxelPolleres, Sandro, +1.216.445.aaaa

19:17:10 <AxelPolleres> rrsagent, make records public

rrsagent, make records public

19:17:31 <sandro> rrsagent, pointer?

Sandro Hawke: rrsagent, pointer?

19:17:31 <RRSAgent> See http://www.w3.org/2010/02/24-sparql-ent-irc#T19-17-31

RRSAgent IRC Bot: See http://www.w3.org/2010/02/24-sparql-ent-irc#T19-17-31

19:19:20 <sandro> ewwwww.    commonscribe doesn't want to handle this irc log being on a strange channel.

Sandro Hawke: ewwwww. commonscribe doesn't want to handle this irc log being on a strange channel.

19:21:55 <bglimm> hm, what's so strange about it. Should I pick a different one for the next teleconf?

Birte Glimm: hm, what's so strange about it. Should I pick a different one for the next teleconf?

19:22:57 <sandro> it's just looking for #sparql.    maybe easier to use that, next time, since there's no conflict with the WG at that time.

Sandro Hawke: it's just looking for #sparql. maybe easier to use that, next time, since there's no conflict with the WG at that time.

19:23:34 <bglimm> ok. Whoever is not interested in entailments can just ignore us ;-)

Birte Glimm: ok. Whoever is not interested in entailments can just ignore us ;-)



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This revision (#2) generated 2010-02-24 19:34:55 UTC by 'unknown', comments: None