ISSUE-59: Syntactic sugar for triples maps that only have a single predicate-object map
simple-triples-maps
Syntactic sugar for triples maps that only have a single predicate-object map
- State:
- POSTPONED
- Product:
- R2RML
- Raised by:
- Richard Cyganiak
- Opened on:
- 2011-07-29
- Description:
- Currently, a triples map has exactly one subject map, and then a number of predicate-object maps. However, there is a case that we can expect to see reasonably often where a triples map has exactly one predicate-object map. This is when an n:m link table is mapped to a single set of triples.
In the interest of making simple things simple and hard things possible, this case could be simplified by removing the intermediate predicate-object map node and just sticking its predicate map(s) and object map directly onto the triples map. This yields a much more readable form.
Example:
Student(s_id, name)
Course(c_id, title)
Enrolled(s_id, c_id)
Where Enrolled is the many-to-many relationship. The current R2RML mapping would be:
<#LinkMap_1_2>
rr:logicalTable [ rr:tableName "enrolled" ];
rr:subjectMap [ rr:template "http://data.example.com/student/{s_id}" ];
rr:predicateObjectMap [
rr:predicateMap [ rr:predicate ex:isEnrolled ];
rr:objectMap [ rr:template "http://data.example.com/course/{c_id}" ];
].
With syntactic sugar, it would become:
<#LinkMap_1_2>
rr:logicalTable [ rr:tableName "enrolled" ];
rr:subjectMap [ rr:template "http://data.example.com/student/{s_id}" ];
rr:predicateMap [ rr:predicate ex:isEnrolled ];
rr:objectMap [ rr:template "http://data.example.com/course/{c_id}" ].
The spec would say: A triples map MAY have exactly one object map and one or more predicate maps. If these are present, then they form an implicit predicate-object map. This would be a simple change.
This has been proposed by Richard here [1] and seconded by Juan here [2].
[1]: http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2011Jul/0169.html
[2]: http://lists.w3.org/Archives/Public/public-rdb2rdf-wg/2011Jul/0170.html - Related Actions Items:
- No related actions
- Related emails:
- Re: LC publication (from souripriya.das@oracle.com on 2011-09-15)
- Re: LC publication (from michael.hausenblas@deri.org on 2011-09-15)
- Re: LC publication (from souripriya.das@oracle.com on 2011-09-15)
- Re: LC publication (from souripriya.das@oracle.com on 2011-09-15)
- Re: LC publication (from michael.hausenblas@deri.org on 2011-09-15)
- Re: LC publication (from souripriya.das@oracle.com on 2011-09-15)
- Re: LC publication (from souripriya.das@oracle.com on 2011-09-15)
- Re: LC publication (from michael.hausenblas@deri.org on 2011-09-15)
- Re: LC publication (from souripriya.das@oracle.com on 2011-09-15)
- Re: LC publication (from michael.hausenblas@deri.org on 2011-09-15)
- Re: LC publication (from michael.hausenblas@deri.org on 2011-09-15)
- Re: LC publication (from souripriya.das@oracle.com on 2011-09-15)
- Re: LC publication (from michael.hausenblas@deri.org on 2011-09-15)
- Re: LC publication (from bvillazon@fi.upm.es on 2011-09-15)
- Re: LC publication (from SOURIPRIYA.DAS@oracle.com on 2011-09-14)
- Re: LC publication (from bvillazon@fi.upm.es on 2011-09-14)
- Re: LC publication (from bvillazon@fi.upm.es on 2011-09-14)
- Re: LC publication (from souripriya.das@oracle.com on 2011-09-14)
- LC publication (from michael.hausenblas@deri.org on 2011-09-14)
- Minutes of 2011-09-13 telecon (from michael.hausenblas@deri.org on 2011-09-13)
- Re: RDB2RDF WG agenda for 2011-09-13 meeting 1600 UTC (from bvillazon@fi.upm.es on 2011-09-13)
- RDB2RDF WG agenda for 2011-09-13 meeting 1600 UTC (from Michael.Hausenblas@deri.org on 2011-09-12)
- Re: Please review: syntactic sugar and polishing (ISSUE-54, ISSUE-56, ISSUE-59, ISSUE-60) (from dmcneil@revelytix.com on 2011-08-30)
- Re: Please review: syntactic sugar and polishing (ISSUE-54, ISSUE-56, ISSUE-59, ISSUE-60) (from richard@cyganiak.de on 2011-08-30)
- Re: Please review: syntactic sugar and polishing (ISSUE-54, ISSUE-56, ISSUE-59, ISSUE-60) (from boris.villazon@deri.org on 2011-08-30)
- Re: Please review: syntactic sugar and polishing (ISSUE-54, ISSUE-56, ISSUE-59, ISSUE-60) (from dmcneil@revelytix.com on 2011-08-30)
- Re: Please review: syntactic sugar and polishing (ISSUE-54, ISSUE-56, ISSUE-59, ISSUE-60) (from dmcneil@revelytix.com on 2011-08-29)
- Re: Please review: syntactic sugar and polishing (ISSUE-54, ISSUE-56, ISSUE-59, ISSUE-60) (from richard@cyganiak.de on 2011-08-29)
- Re: Please review: syntactic sugar and polishing (ISSUE-54, ISSUE-56, ISSUE-59, ISSUE-60) (from dmcneil@revelytix.com on 2011-08-29)
- Please review: syntactic sugar and polishing (ISSUE-54, ISSUE-56, ISSUE-59, ISSUE-60) (from richard@cyganiak.de on 2011-08-27)
- Re: Status of the R2RML document and going last call (from michael.hausenblas@deri.org on 2011-08-02)
- Status of the R2RML document and going last call (from richard@cyganiak.de on 2011-08-02)
- Re: RDB2RDF WG agenda for 2011-08-02 meeting 1600 UTC (from marcelo.arenas1@gmail.com on 2011-08-02)
- Re: RDB2RDF WG agenda for 2011-08-02 meeting 1600 UTC (from ashok.malhotra@oracle.com on 2011-08-02)
- RDB2RDF WG agenda for 2011-08-02 meeting 1600 UTC (from michael.hausenblas@deri.org on 2011-07-30)
- Re: Many-to-Many table in R2RML (from juanfederico@gmail.com on 2011-07-29)
- Re: Many-to-Many table in R2RML (from richard@cyganiak.de on 2011-07-29)
- ISSUE-59 (simple-triples-maps): Syntactic sugar for triples maps that only have a single predicate-object map [R2RML] (from sysbot+tracker@w3.org on 2011-07-29)
Related notes:
Done:
http://www.w3.org/2001/sw/rdb2rdf/r2rml/#dfn-implicit-predicate-object-map
http://www.w3.org/2001/sw/rdb2rdf/r2rml/#example-m2m
Resolved as of [1]:
[[
RESOLUTION: Remove section http://www.w3.org/2001/sw/rdb2rdf/r2rml/#dfn-implicit-predicate-object-map that contains syntactic sugar for single predicate-object map and postpone ISSUE-59
]]
[1] http://www.w3.org/2011/09/13-RDB2RDF-minutes.html#item05Michael Hausenblas, 13 Sep 2011, 17:48:15
Display change log