Chatlog 2010-09-28

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13:58:55 <RRSAgent> RRSAgent has joined #sparql
13:58:55 <RRSAgent> logging to
13:58:57 <trackbot> RRSAgent, make logs world
13:58:57 <Zakim> Zakim has joined #sparql
13:58:59 <trackbot> Zakim, this will be 77277
13:58:59 <Zakim> ok, trackbot; I see SW_(SPARQL)10:00AM scheduled to start in 2 minutes
13:59:00 <LeeF> zakim, this will be SPARQL
13:59:00 <trackbot> Meeting: SPARQL Working Group Teleconference
13:59:01 <trackbot> Date: 28 September 2010
13:59:02 <Zakim> ok, LeeF, I see SW_(SPARQL)10:00AM already started
13:59:07 <Zakim> +MattPerry
13:59:40 <Zakim> +LeeF
13:59:40 <Zakim> + +1.310.729.aaaa
13:59:40 <bglimm> All circuits are busy now for me too :-(
13:59:49 <SteveH_> yup :(
13:59:53 <kasei> Zakim, aaaa is me
13:59:53 <Zakim> +kasei; got it
14:00:16 <LeeF> I haven't seen any W3C notices, which doesn't really mean much.
14:00:26 <Zakim> +pgearon
14:00:34 <Zakim> +??P26
14:00:35 <LeeF> Regrets: Axel, Chime, Alex
14:00:41 <AndyS> zakim, ??P26 is me
14:00:41 <Zakim> +AndyS; got it
14:01:03 <Zakim> +Sandro
14:01:13 <LeeF> Scribenick: MattPerry
14:01:21 <Zakim> +[IPcaller]
14:01:28 <SteveH_> Zakim, [IPcaller] is me
14:01:28 <Zakim> +SteveH_; got it
14:01:30 <Zakim> +bglimm
14:01:38 <Souri> Souri has joined #sparql
14:01:45 <bglimm> Zakim, mute me
14:01:53 <Zakim> bglimm should now be muted
14:01:56 <Zakim> +??P30
14:02:18 <Zakim> +Souri
14:02:33 <NickH> Zakim, ??P30 is me
14:02:33 <Zakim> +NickH; got it
14:04:05 <Zakim> +Garlik
14:04:10 <Zakim> -SteveH_
14:04:14 <MattPerry> LeeF: want to go through documents to see status for next round of publication
14:04:18 <SteveH> Zakim, Garlik is temporarily me
14:04:18 <Zakim> +SteveH; got it
14:04:29 <OlivierCorby> Not able to join by tel, system refuses ...
14:04:46 <MattPerry> LeeF: not in a position to go over Let/Bind this week but maybe next week
14:04:47 <LeeF> Agenda:
14:04:55 <LeeF> PROPOSED: Approve minutes at
14:05:12 <Zakim> +OlivierCorby
14:05:19 <OlivierCorby> Hi 
14:05:37 <LeeF> RESOLVED: Approve minutes at
14:05:57 <MattPerry> topic: query document reviews
14:06:37 <MattPerry> LeeF: issues: BINDING keyword and isNumeric function and errors in aggregates
14:06:48 <LeeF> subtopic: semantics of BINDINGS
14:06:58 <LeeF>
14:07:35 <LeeF> """
14:07:36 <LeeF>    for each row:
14:07:36 <LeeF>      substitute all occurrences of named variables in the query
14:07:36 <LeeF>      execute modified query
14:07:37 <LeeF> """
14:08:42 <LeeF> """
14:08:43 <LeeF> SELECT *
14:08:43 <LeeF> { ?s ?p ?o . FILTER ( ?o < ?v ) }
14:08:43 <LeeF> BINDINGS ?v { (1) (2) }
14:08:44 <LeeF> """
14:09:26 <LeeF> this bindings list has two rows, each with one value
14:09:29 <MattPerry> AndyS: for each binding set, substitute into query and then execute query
14:10:09 <MattPerry> AndyS: in federated doc, turn binding into table and then join with query
14:10:33 <SteveH> q+
14:10:36 <kasei> is this a better example for this discussion (whether the results have any variables bound)?: select * where {} bindings ?s { (1) (2) }
14:10:47 <LeeF> ack SteveH
14:11:18 <MattPerry> SteveH: our implementation works more like the join description
14:12:09 <LeeF> Not so sure if that's a good example, Greg - wouldn't that turn the same way either way?
14:12:13 <MattPerry> SteveH: for Greg's example we would get ?s bound to 1 and 2
14:12:23 <AndyS> kasei, independent design point - can make ?v visible of * or not for either design
14:13:01 <OlivierCorby> What about variables in minus ?
14:13:30 <kasei> I share SteveH's concern about optimization.
14:13:56 <ericP> ericP has joined #sparql
14:14:31 <ericP> Zakim, please dial ericP-office
14:14:31 <Zakim> ok, ericP; the call is being made
14:14:32 <Zakim> +EricP
14:15:06 <MattPerry> AndyS: this definition is an improvement in federated query
14:15:09 <OlivierCorby> q+
14:15:21 <LeeF>
14:16:44 <LeeF> ack OlivierCorby
14:16:52 <MattPerry> LeeF: issue is that some variables, e.g. those in filter, can't get  their values from a join
14:17:31 <AndyS> q+
14:17:35 <MattPerry> Olivier: what about MINUS, can it be a substitution?
14:17:40 <LeeF> ack AndyS
14:17:45 <ericP> q+
14:17:57 <MattPerry> AndyS: I would think that substitution would work for MINUS
14:18:12 <SteveH> I don't like the approach of conflating parameterised queries and pre-binding, they're different
14:18:27 <LeeF> ack ericP
14:19:19 <MattPerry> ericP: biggest issue is the FILTER issue
14:21:17 <SteveH> q+ to ask why bindings goes at the "end"
14:21:57 <MattPerry> ... I would go with the same semantics we used with OPTIONAL, the FILTER works on the previous set of variables
14:22:07 <LeeF> ack SteveH
14:22:07 <Zakim> SteveH, you wanted to ask why bindings goes at the "end"
14:23:23 <AndyS> q+
14:23:28 <MattPerry> ericP: BINDINGS go at the end because you may want to stream the result, and this is only possible if the query is done before you get the bindings 
14:24:52 <LeeF> ack AndyS
14:25:35 <MattPerry> AndyS: if you see the query first, you can do a "prepare" on the query
14:26:41 <MattPerry> ericP: optional has a left pattern, right pattern and filter ... the filter works on the left and right pattern
14:27:03 <kasei> I don't think people would ever figure that out.
14:27:05 <MattPerry> ... filters now have a left and right where right comes from the BINDINGS
14:28:29 <MattPerry> ericP: I think that if people are given a mandate for substitution, they will still figure out a way to do it with joins but this may be difficult for people
14:28:44 <SteveH> +1 to ericP 
14:29:22 <MattPerry> AndyS: substitution is not a new operation in the algebra, but a new join is a new operation
14:29:31 <SteveH> that's the problem
14:30:09 <MattPerry> SteveH: the problem is implementing a substitution operation
14:31:18 <MattPerry> AndyS: I think the FILTER case is the important one
14:31:45 <MattPerry> LeeF: is the working group motivated to make the FILTER case work
14:31:48 <AndyS> q+
14:32:27 <kasei> q+
14:32:29 <LeeF> ack AndyS
14:32:30 <ericP> i'm happy to leave it out for now
14:32:35 <ericP> but i'm not the alpha team contact
14:33:10 <MattPerry> SteveH: BINDINGS keyword does not imply substitution to me
14:33:15 <LeeF> ack, kasei
14:33:31 <LeeF> ack kasei
14:34:11 <MattPerry> kasei: I agree with SteveH on most of the issues ... BINDINGS imply a join to me
14:34:50 <SteveH> well put kasei 
14:34:57 <MattPerry> ... BINDINGS should give same execution but just a subset of the results ... substitution could give different results
14:35:06 <pgearon> +1 to kasei's POV
14:36:11 <LeeF> straw poll: should the values in rows in the BINDINGS clause be available within FILTERs etc. within the query a la AndyS's proposal?
14:36:35 <SteveH> that statement is not correct
14:37:34 <MattPerry> SteveH: this is about what happens when you have a variable in Filter but not in the graph pattern
14:38:05 <LeeF> straw poll: should the BINDINGS clause have Join or Substitution semantics?
14:38:21 <kasei> Join
14:38:23 <SteveH> Join
14:38:28 <pgearon> join
14:38:28 <ericP> join
14:38:29 <NickH> Join
14:38:31 <MattPerry> join
14:38:40 <bglimm> 0 (not enough understanding of the issues)
14:38:46 <Souri> +1 to Andy's substitution proposal (if I understand it correctly, substitution of the values from each binding row and then querying would return some results)
14:38:47 <OlivierCorby> 0 too
14:39:08 <LeeF> 0
14:39:12 <ericP> 7
14:39:13 <AndyS> filter visibility
14:39:14 <sandro> 0 
14:40:00 <SteveH> q+ to ask about templating
14:40:07 <LeeF> ack SteveH
14:40:07 <Zakim> SteveH, you wanted to ask about templating
14:40:27 <LeeF> The group has general consensus to keep the semantics of BINDINGS as is for now.
14:40:27 <MattPerry> SteveH: is templating on our to-do list?
14:40:45 <MattPerry> LeeF: templating missed the cut for 1.1
14:41:11 <MattPerry> subtopic: isNumeric
14:41:16 <LeeF>
14:41:17 <SteveH> +1 to isNumeric()
14:42:13 <LeeF> SUM(?x)
14:42:13 <MattPerry> SteveH: isNumeric is very useful for numeric operations due to the weak typing
14:42:47 <MattPerry> SteveH: right now, we go to xpath numeric-add operation
14:43:02 <LeeF> SUM(IF(isNumeric(?x), ?x, 0))
14:43:02 <MattPerry> ... a date, for example, will give a type error
14:43:18 <AndyS> sum("a") is legal :-)
14:43:28 <SteveH> AndyS, yeah, semi-deliberate :)
14:43:31 <LeeF>
14:44:14 <LeeF> PROPOSED: Include an isNumeric function in SPARQL 1.1 
14:44:27 <AndyS> seconded
14:44:45 <LeeF> RESOLVED: Include an isNumeric function in SPARQL 1.1
14:45:13 <AndyS> SteveH, I implemented the more obvious way
14:45:29 <SteveH> AndyS, which is that? :)
14:45:31 <MattPerry> topic: go through document reviews
14:45:40 <AndyS> sum("a") -> error
14:45:48 <MattPerry> subtopic: query
14:45:54 <SteveH> ah, right, that's what I'm going to write in when I have time
14:46:06 <AndyS> like sum("a"+0) or sum("a", 0) -> error
14:46:12 <SteveH> right
14:46:20 <ericP> q+ to ask if federation is rolled in
14:46:48 <LeeF> ack, ericP
14:46:51 <LeeF> ack ericP
14:46:51 <Zakim> ericP, you wanted to ask if federation is rolled in
14:47:13 <MattPerry> ericP: who is editor of federation?
14:48:45 <MattPerry> ericP: I can take a look at the comments for federation
14:49:21 <MattPerry> I fine with it
14:49:24 <kasei> me too
14:49:28 <MattPerry> s/I/I'm
14:49:33 <SteveH> actually, I'd like to make a couple of edits, based on reviews
14:49:38 <SteveH> if that wont gum up the process
14:49:41 <SteveH> otherwise its fine
14:50:45 <MattPerry> SteveH: some non-algebraic changes I would like to make
14:51:23 <MattPerry> LeeF: should be fine if you do it by Friday
14:51:47 <LeeF> PROPOSED: Publish + Steve's wording changes in response to Greg's comments as Working Draft
14:52:37 <LeeF> PROPOSED: Publish + editorial changes in response to Greg's comments as Working Draft
14:52:45 <AndyS> 0.5
14:52:50 <SteveH> 1
14:53:43 <MattPerry> AndyS: would like to process all the comments first
14:54:30 <SteveH> I'm also not swapped in on that
14:54:32 <LeeF>
14:55:12 <MattPerry> LeeF: lets hold off on publishing for now and try to go through all docs next week
14:55:44 <AndyS> q+ to ask about isNumeric (get in if possible?)
14:56:18 <SteveH> and fix sum("a") on same basis
14:56:18 <LeeF> ack AndyS
14:56:18 <Zakim> AndyS, you wanted to ask about isNumeric (get in if possible?)
14:56:20 <MattPerry> AndyS: I can try to put in isNumeric
14:57:14 <bglimm> Zakim, unmute me
14:57:14 <Zakim> bglimm should no longer be muted
14:57:48 <MattPerry> kasei: will summarize what changes went into service description
14:58:08 <MattPerry> bglimm: service description is ready from my point of view
14:58:20 <MattPerry> ... entailment is awaiting LeeF's review
14:58:45 <MattPerry> Olivier: entilment is ok with me
14:58:54 <MattPerry> s/entilment/entailment
14:59:02 <SteveH> bye all
14:59:03 <MattPerry> bye
14:59:06 <Zakim> -LeeF
14:59:08 <Zakim> -pgearon
14:59:08 <NickH> bye!
14:59:10 <Zakim> -SteveH
14:59:11 <LeeF> Matt, thanks very much for scribingg
14:59:12 <Zakim> -Sandro
14:59:14 <Zakim> -bglimm
14:59:16 <Zakim> -kasei
14:59:18 <Zakim> -MattPerry
14:59:20 <Zakim> -EricP
14:59:22 <Zakim> -NickH
14:59:24 <Zakim> -Souri
14:59:30 <Zakim> -OlivierCorby
14:59:32 <Zakim> -AndyS
14:59:36 <Zakim> SW_(SPARQL)10:00AM has ended
14:59:38 <Zakim> Attendees were MattPerry, LeeF, +1.310.729.aaaa, kasei, pgearon, AndyS, Sandro, SteveH_, bglimm, Souri, NickH, SteveH, OlivierCorby, EricP
15:03:19 <OlivierCorby> OlivierCorby has left #sparql
17:05:23 <Zakim> Zakim has left #sparql
17:33:19 <AndyS> Defining what it means to be numeric.  Reusing some of ericP's fine words.
17:51:34 <AndyS> isNumeric added to rq25.  Note: the lexical form of the term must be valid ("1220"^^xsd:byte is not) to make it consistent with numeric operations.  And RDF-MT.
19:34:05 <AndyS> AndyS has joined #sparql
20:00:19 <SteveH> SteveH has joined #sparql
21:43:53 <LeeF> LeeF has joined #sparql
22:00:36 <karl> karl has joined #sparql