RDB2RDF Working Group Teleconference -- 06 Sep 2011

<trackbot> Date: 06 September 2011

<scribe> scribenick: mhausenblas

Admin

PROPOSAL: Accept the minutes of last meeting http://www.w3.org/2011/08/30-rdb2rdf-minutes.html with the correction by David in http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2011Aug/0185.html

<nunolopes> +1

RESOLUTION: Accept the minutes of last meeting http://www.w3.org/2011/08/30-rdb2rdf-minutes.html with the correction by David in http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2011Aug/0185.html

R2RML

ISSUE-61?

<trackbot> ISSUE-61 -- Re-using public entity identifiers - look-up table -- pending review

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/61

ISSUE-66?

<trackbot> ISSUE-66 -- Translation Scheme as proposed seems too complicated for the simple task of mapping <DB value(s), RDF term> -- open

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/66

ISSUE-29?

<trackbot> ISSUE-29 -- Require blank node and IRI identifier expressions to produce strings -- pending review

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/29

<dmcneil> +q

David: Sec 11.5 - I don't understand what it means to use base64 encoding

<dmcneil> ericP - indeed :)

Michael: David, could you please ask Richard and the ML directly to resolve this?

David: Will do

<Ashok> When converting from SQL to XML binary data why do we need to convert to string first? Why not convert directly to base64?

ISSUE-48?

<trackbot> ISSUE-48 -- Mapping SQL datatypes to RDF -- pending review

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/48

[[

PROPOSAL: Close ISSUE-48 as it is addressed in http://www.w3.org/2001/sw/rdb2rdf/r2rml/#datatype-conversions

]]

<dmcneil> +q

David: In fact my question was re ISSUE-48

[[

PROPOSAL: Close ISSUE-29; all places that interpret SQL values as

string now use "conversion to string"

]]

<seema> +1

<dmcneil> +1

<ivan> +1

RESOLUTION: Close ISSUE-29; all places that interpret SQL values as string now use "conversion to string"

ISSUE-51?

<trackbot> ISSUE-51 -- Handling of ill-typed literals -- pending review

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/51

[[

PROPOSAL: Close ISSUE-51; the spec now demands that “supported RDF

types” MUST raise data error, and other types MAY raise data error

]]

<dmcneil> +1

<ivan> +1

<Ashok> +1

RESOLUTION: Close ISSUE-51; the spec now demands that “supported RDF types” MUST raise data error, and other types MAY raise data error

ISSUE-57?

<trackbot> ISSUE-57 -- R2RML doesn't allow R2RML documents in RDF/XML syntax -- open

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/57

[[

PROPOSAL: Lack of consensus on the syntax question is noted in the issue box in Section 4.2, which presents both options. A decision on the question will be postponed until after Last Call. This closes ISSUE-57.

]]

Seema: We're working on the content of box

<nunolopes> +1

<MacTed> presuming there's an action tracking the ongoing work...

<dmcneil> (I emailed the list with my question concerning ISSUE-48)

RESOLUTION: Lack of consensus on the syntax question is noted in the issue box in Section 4.2, which presents both options. A decision on the question will be postponed until after Last Call. This closes ISSUE-57.

See http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2011Aug/0150.html for details re ISSUES 54, 56, 59, and 60.

[[ PROPOSAL: Close ISSUES 54, 56, 59, 60; they are addressed in the latest draft.

]]

<dmcneil> +q

David: I think some are more in-depth changes

<ivan> ISSUE-59?

<trackbot> ISSUE-59 -- Syntactic sugar for triples maps that only have a single predicate-object map -- pending review

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/59

Seema: I think ISSUE-59 should be left open

<dmcneil> +q

[[ PROPOSAL: Close ISSUES 54, 56, 60; they are addressed in the latest draft. ]]

ack q?

<ivan> ISSUE-54?

<trackbot> ISSUE-54 -- Simpler constant-valued term maps -- pending review

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/54

David: Seems that the solution to ISSUE-54 changes the semantics of R2RML

Ivan: I think, maybe, if we have a 2nd LC round, last minute change should come not in a batch mail but separate

Michael: I agree

PROPOSAL: Close ISSUES 54, 56, 60; they are addressed in the latest draft.

<dmcneil> +1

<ivan> +1

RESOLUTION: Close ISSUES 54, 56, 60; they are addressed in the latest draft.

ISSUE-55?

<trackbot> ISSUE-55 -- Nested predicate-object maps -- open

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/55

PROPOSAL: Postpone ISSUE-55, this could be considered for R2RML 1.1

<dmcneil> +1

<MacTed> +1

<nunolopes> +1

<seema> +1 for postponing

<ivan> +1

RESOLUTION: Postpone ISSUE-55, this could be considered for R2RML 1.1

ISSUE-58?

<trackbot> ISSUE-58 -- R2RML doesn't introduce Turtle well enough -- open

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/58

<Zakim> ericP, you wanted to say we can make purely editorial changes after LC

Eric: we can always point to the RDF WG Turtle doc, pure editorial changes are OK

PROPOSAL: Re-categorise ISSUE-58, it is an editorial/didactic issue and can be addressed after Last Call

<ivan> +1

<MacTed> oh, so we use British English? American is "categorize" :-)

<MacTed> +1

RESOLUTION: Re-categorize ISSUE-58, it is an editorial/didactic issue and can be addressed after Last Call

<scribe> ACTION: Hausenblas to re-categorize ISSUE-58 [recorded in http://www.w3.org/2011/09/06-RDB2RDF-minutes.html#action01]

<trackbot> Created ACTION-157 - Re-categorize ISSUE-58 [on Michael Hausenblas - due 2011-09-13].

DM

ISSUE-65?

<trackbot> ISSUE-65 -- For uniformity and performance, "literal" triples must be always generated for each child table column in a foreign key -- open

<trackbot> http://www.w3.org/2001/sw/rdb2rdf/track/issues/65

PROPOSAL: For a foreign key of any arity, the reference property IRI is of the form <Table#ref-attr1-attr2-...-attrn>. This will address ISSUE-65

Juan: We went for 'ref' and '-' for the template

<ivan> +1 (it is as good as any scheme...)

Eric: both '-' and '.' are technically allowed
... the downside of the dot is that it can confuse with the schema (DB/table) identifier
... the downside of the dash is that you'd need to escape the attribute value

<ericP> the dot variant

Eric: we can have both options in the DM document and ask for feedback

<ericP> http://www.w3.org/2001/sw/rdb2rdf/directMapping/explicitFK#defn-custom-url-encode

<MacTed> so this is an example -- pencil:_ <TaskAssignments#ref.project.deptName.deptCity> _:c .

<MacTed> vs -- pencil:_ <TaskAssignments#ref-project-deptName-deptCity> _:c .

<ericP> imo, <http://foo.example/Table/attr1=value1,attr2=value2> is intuitive

<ericP> <http://foo.example/Table/attr1.value1-attr2.value2> is easy to abbreviate with prefixes in turtle, SPARQL, RIF,...

(discussion on pro and cons of all the possible solutions)

Michael: how about <Table#ref,attr1,attr2,...,attrn> and <http://foo.example/Table/attr1=value1,attr2=value2>

<ericP> the ','s as separators has a pretty big cost in terms of expressing mapping rules

Ivan: I agree with Michael that asking others now is somehow complicated

Ashok: When I suggested asking SPARQL people I didn't mean the WG but people that have experience here

<ericP> <http://foo.example/Table/attr1.value1-attr2.value2> row identifier

<ericP> <http://foo.example/Table/attr1-attr2> reference predicate

<ericP> PREFIX inst: <http://foo.example/Table/> .

<ericP> PREFIX scheme: <http://foo.example/Table#> .

<ericP> inst:attr1.7-attr2.13 schema:fname "Bob" .

<scribe> ACTION: Eric to write up implications re dot vs. slash etc. for ISSUE-65 [recorded in http://www.w3.org/2011/09/06-RDB2RDF-minutes.html#action02]

<trackbot> Created ACTION-158 - Write up implications re dot vs. slash etc. for ISSUE-65 [on Eric Prud'hommeaux - due 2011-09-13].

[meeting adjourned]

trackbot, end telecon

- DRAFT -

RDB2RDF Working Group Teleconference

06 Sep 2011

Attendees

Contents

Admin

R2RML

DM

Summary of Action Items

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