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Re: Agenda SPARQL TC 2009-01-05

From: Andy Seaborne <andy.seaborne@talis.com>
Date: Tue, 05 Jan 2010 15:19:47 +0000
Message-ID: <4B435893.2000808@talis.com>
To: Birte Glimm <birte.glimm@comlab.ox.ac.uk>
CC: Axel Polleres <axel.polleres@deri.org>, SPARQL Working Group <public-rdf-dawg@w3.org>


On 05/01/2010 3:07 PM, Birte Glimm wrote:
> So what do you suggest to change?

There are lots of comments being made on the query document at the 
moment in preparation for the next round of publication. I am 
prioritising comments on the new features.

	Andy

> Birte
>
> 2010/1/5 Andy Seaborne<andy.seaborne@talis.com>:
>>
>>
>> On 05/01/2010 2:27 PM, Axel Polleres wrote:
>>>
>>> I don't see any problems with that reformulation and it seems to be
>>> clearer
>>> indeed to include that in the definition. Andy? Steve?
>>
>> I don't think changing solely the definition of Pattern Instance Mapping is
>> the best way to do this.
>>
>>         Andy
>>
>>>
>>> We probably won't get there today, but will keep it in mind to bring
>>> this up separately in the agenda in some of the next TCs.
>>>
>>> Axel
>>>
>>> On 5 Jan 2010, at 14:14, Birte Glimm wrote:
>>>
>>>> The current definition says:
>>>> A Pattern Instance Mapping, P, is the combination of an RDF instance
>>>> mapping, σ, and solution mapping, μ. P(x) = μ(σ(x))
>>>>
>>>> below the definition there the new sentence:
>>>> For a BGP 'x', P(x) denotes the result of replacing blank nodes b in x
>>>> for which σ is defined with σ(b) and all variables v in x for which μ
>>>> is defined with μ(v).
>>>>
>>>> I suggest to put that sentence into the definition and relate it to
>>>> P(x) = μ(σ(x)). For example:
>>>> A Pattern Instance Mapping, P, is the combination of an RDF instance
>>>> mapping, σ, and solution mapping, μ. For a BGP x, P(x) denotes the
>>>> result of replacing each blank node b in x for which σ is defined with
>>>> σ(b) and each variable v in x for which μ is defined with μ(v), also
>>>> denoted as P(x) = μ(σ(x)).
>>>>
>>>> Basically, my goal is to make this definition clearer. I think the
>>>> definition should say what x is since it is not a defined term like
>>>> RDF-T for example. I also think the definition should say what it
>>>> means to apply a solution mapping or an RDF instance mapping to a BGP.
>>>> These are mappings from variables/bnodes to terms. It is never defined
>>>> what the functions to with BGPs. They don't map BGPs to terms. Here it
>>>> is assumed that they replace
>>>> variables/bnodes with the corresponding mappings. That has to be said
>>>> IMO. It can all be guessed, but it is a definition and it is an
>>>> important definition. I do not suggest to change anything in the
>>>> meaning. For me that still counts as errata because the definition
>>>> just did not mention what it should have mentioned.
>>>>
>>>> Anyway, I just wanted the spec to be clear, but if there are
>>>> objections, I will not spend any more time on this issue.
>>>>
>>>> Birte
>>>>
>>>> 2010/1/4 Axel Polleres<axel.polleres@deri.org>:
>>>>>
>>>>> Hi Birte,
>>>>>
>>>>>> Query 1.1 uses the Query 1.0 definition and adds a sentence below to
>>>>>> clarify this, but I would prefer to actually extend the definition
>>>>>> accordingly if the WG is not opposed to that. IMO, the definition
>>>>>> leaves a lot for readers to figure out themselves and it is quite an
>>>>>> essential definition. Such a change would not change the meaning of
>>>>>> the definition, but extend it so that it is clear what is meant.
>>>>>
>>>>> Do you have a concrete proposal for improval to extend the definition?
>>>>> I'd assume if so, we can discuss it, although probably there is not
>>>>> enough  time left to agree and include it in this round, so I'd prefer
>>>>> to
>>>>> postpone this issue to after the next WD round.
>>>>>
>>>>> best,
>>>>> Axel
>>>>>
>>>>> On 4 Jan 2010, at 15:00, Birte Glimm wrote:
>>>>>
>>>>>> Axel,
>>>>>> if there is some time in tomorrow's telecon, I would like to discuss
>>>>>> whether it is possible to clarify the definition of Pattern Instance
>>>>>> Mapping in Query 1.1.
>>>>>>
>>>>>> The Query 1.0 definition says:
>>>>>> A Pattern Instance Mapping, P, is the combination of an RDF instance
>>>>>> mapping, σ, and solution mapping, μ. P(x) = μ(σ(x))
>>>>>>
>>>>>> The problem is that it is never said what x is and readers have to
>>>>>> guess that it is a BGP. Even if they guess that x is a BGP, then it is
>>>>>> still the case that sigma and mu are only defined for blank nodes and
>>>>>> variables as input, so readers again have to guess that in this case
>>>>>> it is meant that the blank nodes and variables in the BGP x are
>>>>>> replaced with the values given by mu and sigma.
>>>>>>
>>>>>> Query 1.1 uses the Query 1.0 definition and adds a sentence below to
>>>>>> clarify this, but I would prefer to actually extend the definition
>>>>>> accordingly if the WG is not opposed to that. IMO, the definition
>>>>>> leaves a lot for readers to figure out themselves and it is quite an
>>>>>> essential definition. Such a change would not change the meaning of
>>>>>> the definition, but extend it so that it is clear what is meant.
>>>>>
>>>>> Do you have a concrete proposal to extend the definition?
>>>>>
>>>>>> Birte
>>>>>>
>>>>>>
>>>>>> 2010/1/4 Axel Polleres<axel.polleres@deri.org>:
>>>>>>>
>>>>>>> Dear all,
>>>>>>>
>>>>>>> first of all, Happy 2010 and looking fwd to welcome you to our first
>>>>>>> TC this year!
>>>>>>> On Tuesday, we obviously want to check the status of the reviews and
>>>>>>> go through them as far
>>>>>>> as there are any critical comments. We should also check the schedule
>>>>>>> in case there are reviews
>>>>>>> missing still, since we want to make a decision to publish (based on
>>>>>>> reviews&    subsequent
>>>>>>> updates made by editors) in two weeks at the latest.
>>>>>>>
>>>>>>> In case we still have time left with all that on Tuesday (given the
>>>>>>> speed we rushed through all
>>>>>>> docs in the last TC before christmas, you never know), I'd like to
>>>>>>> have a look over the
>>>>>>> update ISSUEs mentioned in Paul's and Andy's mails [1,2].
>>>>>>>
>>>>>>> 1.
>>>>>>> http://lists.w3.org/Archives/Public/public-rdf-dawg/2009OctDec/0628.html
>>>>>>> 2.
>>>>>>> http://lists.w3.org/Archives/Public/public-rdf-dawg/2009OctDec/0674.html),
>>>>>>>
>>>>>>> The agenda can be found as usual at:
>>>>>>> http://www.w3.org/2009/sparql/wiki/Agenda-2010-01-05
>>>>>>> Will try to complete links to the reviews sent so far before the TC...
>>>>>>>
>>>>>>> best,
>>>>>>> Axel
>>>>>>>
>>>>>>> ============================
>>>>>>> Call in details
>>>>>>>
>>>>>>> When joining please don't identify yourself verbally; instead,
>>>>>>> identify yourself to Zakim on IRC
>>>>>>>
>>>>>>>         • Date of Call: Tuesday January 05, 2010
>>>>>>>         • Time of Call: 15:00 UK, 10:00 (East US)
>>>>>>>         • Dial-In #: +1.617.761.6200 (Cambridge, MA)
>>>>>>>         • Dial-In #: +33.4.89.06.34.99 (Nice, France)
>>>>>>>         • Dial-In #: +44.117.370.6152 (Bristol, UK)
>>>>>>>         • Participant Access Code: 77277# (SPARQ)
>>>>>>>         • IRC Channel: irc.w3.org port 6665 channel #sparql
>>>>>>> ([irc:irc.w3.org:6665/sparql])
>>>>>>>         • Web-based IRC (member-only):
>>>>>>> http://www.w3.org/2001/01/cgi-irc (Firefox IRC addon: chatzilla)
>>>>>>>         • Duration: 60 minutes
>>>>>>>         • Chair: Axel Polleres
>>>>>>>         • Scribe: Olivier Corby (Scribe List)
>>>>>>>         • Link to Agenda:
>>>>>>> http://www.w3.org/2009/sparql/wiki/Agenda-2010-01-05
>>>>>>>
>>>>>>> [edit] Agenda
>>>>>>>
>>>>>>>         • Admin
>>>>>>>                 • PROPOSED: Approve minutes at
>>>>>>> http://www.w3.org/2009/sparql/meeting/2009-12-22
>>>>>>>                 • Next meeting: 2010-01-12 @ 15:00 UK / 10:00 EST
>>>>>>> (scribe: Alex Passant)
>>>>>>>         • Comment handling - see
>>>>>>> http://www.w3.org/2009/sparql/wiki/Comments
>>>>>>>         • Liaisons - Anything to report?
>>>>>>>                 • RIF WG (Axel)
>>>>>>>                 • RDB2RDF WG (Orri)
>>>>>>>                 • eGov (SteveH)
>>>>>>>         • Document Reviews and schedule for publication:
>>>>>>>                 • http://www.w3.org/2009/sparql/docs/query-1.1/
>>>>>>>                 • http://www.w3.org/2009/sparql/docs/update-1.1/
>>>>>>>                 • http://www.w3.org/2009/sparql/docs/protocol-1.1/
>>>>>>>                 •
>>>>>>> http://www.w3.org/2009/sparql/docs/service-description-1.1/
>>>>>>>                 • http://www.w3.org/2009/sparql/docs/http-rdf-update/
>>>>>>>                 •
>>>>>>> http://www.w3.org/2009/sparql/docs/property-paths/Overview.xml
>>>>>>>                 •
>>>>>>> http://www.w3.org/2009/sparql/docs/entailment/xmlspec.xml
>>>>>>>         • Time allowed: Update ISSUEs, Can we close some? see Paul's
>>>>>>> and Andy's mails.
>>>>>>> [edit] Regrets
>>>>>>>
>>>>>>>         • Lee Feigenbaum
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Dr. Birte Glimm, Room 306
>>>>>> Computing Laboratory
>>>>>> Parks Road
>>>>>> Oxford
>>>>>> OX1 3QD
>>>>>> United Kingdom
>>>>>> +44 (0)1865 283529
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Dr. Birte Glimm, Room 306
>>>> Computing Laboratory
>>>> Parks Road
>>>> Oxford
>>>> OX1 3QD
>>>> United Kingdom
>>>> +44 (0)1865 283529
>>>>
>>>
>>>
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>>
>
>
>
Received on Tuesday, 5 January 2010 15:20:18 GMT

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