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Re: Editorial bugs?

From: Souri Das <Souripriya.Das@oracle.com>
Date: Mon, 01 Nov 2010 10:39:22 -0400
Message-ID: <4CCED11A.5010805@Oracle.com>
To: Ivan Herman <ivan@w3.org>
CC: Richard Cyganiak <richard.cyganiak@deri.org>, Seema Sundara <seema.sundara@oracle.com>, public-rdb2rdf-comments@w3.org
Ivan, Again, thanks for a thorough reading. Please see my comments 
inline. -- Souri.

Ivan Herman wrote:
> Hi Souri,
>
> On Oct 31, 2010, at 19:31 , Souripriya Das wrote:
>
>   
>> Ivan,
>>
>> Thanks for your comments. Please see my reply inline.
>> Also, please note that we will make your suggested changes as part of some other changes we are making to the document to make it easier to understand.
>>
>> Thanks,
>> - Souri.
>>
>> On 10/31/2010 9:04 AM, Ivan Herman wrote:
>>     
>>> Guys,
>>>
>>> I am just in the process of familiarizing myself with r2rml, so I may have misunderstood things, so bear with me. But these might be genuine problems:
>>>
>>> In 3.3.1.1, shouldn't there be '(' and ')' characters surrounding 'Department' || depno ? 
>>>   
>>>
>>>       
>> The '(' and ')' are not necessary, but could be added.
>>     
>
> Ah. That come from my ignorance of the SQL syntax. Still, I believe adding the parentheses is a good idea, to be consistent within the document itself.
>   
I will add the parentheses in the new version.
> [snip]
>
>   
>>> Looking at the A.2.2 example, there is a rr:foreignKeyMap part that does not seem to refer to any specific table in the example, nor does it seem to affect the resulting graphs. (Not being a RDB person I must admit I had problems understanding this part of the spec anyway, an example would be welcome...)
>>>
>>>   
>>>
>>>       
>> That was an error.
>> rr:parentTriplesMap xyz:dept;
>>
>> should have been
>> rr:parentTriplesMap <#TriplesMap1>;
>> This error is present in two other places. These have been corrected in a recent version of Editors' draft.
>>     
>
>
> Aha. That makes it a little bit more understandable. However... isn't it true that, somehow, extra triples generated by this foreign key should also appear in the A.2.2 example? I am not 100% what they should be. Is it something like
>
> <xyz.com/emp/7369> emp:c_ref_deptno _:Department10 .
>
>   
That is correct. We will add it in the new version.
> Plus all the triples generated by the example in A.2.1.?
>   
No additional triples (other than the triple you mentioned above) will 
be generated that will have emp:c_ref_deptno as predicate.
(I may be misunderstanding your comment here. Please elaborate if 
necessary.)
> This is very unclear (for my taste) in the description of the foreign key stuff, which only speaks about the RDF property but does not speak about the object of the generated triple. The triple I have here is just, well, something that makes sense to me...
>   
The object for the predicate corr to a rr:foreignKeyMap is expected to 
be retrieved by the following query:
(it could return multiple objects if the foreign key constraint is not 
really enforcing a many-to-one child-to-parent relationship resulting in 
multiple triples with one child instance as subject)

SELECT parent.<rr:column in rr:subjectMap of rr:parentTriplesMap>
  FROM <rr:logicalTable in rr:parentTriplesMap> parent,
              <rr:logicalTable> child
WHERE <rr:joinCondition>

Would it help if we include a polished version of the above text in the 
rr:foreignKeyMap or rr:ForeignKeyClass section?

--------------
So, for A.2.1, the expected query will be:

SELECT parent.deptId
  FROM
               (
                Select ('_:Department' || deptno) AS deptId
                          , deptno
                          , dname
                          , loc
                 from dept
                ) parent,
                (
                Select ('<xyz.com/emp/' || empno||'>') AS empURI
                         , empno
                         , ename
                         , ('<xyz.com/emp/job/'|| job||'>') AS jobTypeURI
                         , job
                         , deptno
                         , ('<xyz.com/emp/etype/'|| etype||'>') AS 
empTypeURI
                         , etype
                         , ('<xyz.com/graph/'|| job || '/' || 
etype||'>') AS graphURI
                 from emp
                ) child
                WHERE (
                     child.deptno = parent.deptno
                 );



> B.t.w., it would be nice if the generated graphs appeared as a graph figure. It would make it more understandable to me...
>
> Thanks!
>
> Ivan
>
>
>   
>>> I hope this helps
>>>
>>> Thanks!
>>>
>>> Ivan
>>>
>>> ----
>>> Ivan Herman, W3C Semantic Web Activity Lead
>>> Home: 
>>> http://www.w3.org/People/Ivan/
>>>
>>> mobile: +31-641044153
>>> PGP Key: 
>>> http://www.ivan-herman.net/pgpkey.html
>>>
>>> FOAF: 
>>> http://www.ivan-herman.net/foaf.rdf
>>>
>>>
>>>
>>>
>>>
>>>
>>>   
>>>
>>>       
>
>
> ----
> Ivan Herman, W3C Semantic Web Activity Lead
> Home: http://www.w3.org/People/Ivan/
> mobile: +31-641044153
> PGP Key: http://www.ivan-herman.net/pgpkey.html
> FOAF: http://www.ivan-herman.net/foaf.rdf
>
>
>
>
>
>   
Received on Monday, 1 November 2010 14:41:03 GMT

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