- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Sun, 9 May 2010 13:55:37 -0400
- To: "Ezzat, Ahmed" <Ahmed.Ezzat@hp.com>
- Cc: "public-rdb2rdf-wg@w3.org" <public-rdb2rdf-wg@w3.org>
Hi Ahmed, thanks for the input. I'm trying to map these to specific textual suggestions, which the most likely to capture the details needed for a decision by the working group. * Ezzat, Ahmed <Ahmed.Ezzat@hp.com> [2010-05-09 05:26+0000] > > Hi, > > Thanks for putting the effort in generating this document. Below is my feedback: > > 1. The use case section of the document looks fine. > > 2. The requirement section (3) needs work. Below are some comments: > * New uncommon terminologies used which makes it difficult to read: putative, isomorphic, etc. Is isomorphic mapping is a requirement in our R2RML? People use today local + domain mapping and it works (uni-direction)? Is isomorphic requirements comes from future looking and expect the same mapping to be bi-directional (read/write to the DBMS) and hence isomorphic mapping makes sense? We need to discuss this one. The generation of a direct graph would appear to be a requirement as it was the effect of the minimum D2R configuration. > * I thought a simple diagram like option-2 and option-3 in the diagram Juan sent out earlier seems reasonable to add. P.S. option-1 is a special case of option-3. LeeF had asked some questions teasing out the meaning of the diagrams. I was interested in the outcome of that conversation. > * In the relevant community people use local and domain ontology; why we are not using these terms to make it easier for readers? #SHAPE refers to "shared" and "popular" ontologies, which i believe encompass domain ontologies as well as ontologies not focused on a specific domain. (e.g. the use of FOAF to represent people in an employees table). > * Why we are using graphs and labels terms vs RDF tuples and identifiers terms? What's an RDF tuple? Per identifier vs. label, #LABELGEN has a description in terms of identifiers: [[ LABELGEN - Label Generation RDF identifiers for objects in the conceptual model can, in some cases, be generated from a transformation of the schema and data in a tuple representing that conceptual model. ]] I tried "Identifier Generation" instead of "Label Generation", but it I wouldn't know how to defend against the argument "you're not generating identifiers; you're using identifiers to generate labels." I thought that using the graph theory term was safer. > * Section 3.1.4, I am not clear what we are trying to say regarding database connection? RDBMS has its own notion and I suspect in SPARQL there is well defined notion of end point. Is the mapping language is involved in mapping RDBMS connections? D2R, for example, has connection information like: [[ map:MyDatabase a d2rq:Database; d2rq:jdbcDSN "jdbc:mysql://localhost/mydb"; d2rq:jdbcDriver "com.mysql.jdbc.Driver"; d2rq:username "user"; d2rq:password "password". ]] as does FeDeRate: http://swobjects.svn.sourceforge.net/viewvc/swobjects/trunk/tests/7tm_receptors/flat/receptors.map One could argue that this is a combination of a map and connection information (that we should define only the mapping language), but there is also a user benefit to being able to swap implementations and use the same configuration information. Perhaps cygri would refer to this as "standardizing httpd.conf". I'm ambivalent. > * Section 3.1.5 (MicroParsing): I assume the editor is referring to using RDBMS UDF for transformation processing. This seems an implementation detail and should not be included in mapping language specification or requirement? I take "user defined output processing functions" to mean user-defined functions within R2RML (as opposed to SQL). (This came from the original use cases wiki so I'm doing some interpretation here.) I've added: [[ Microparsing can come in many flavors. The RDB2RDF would like feedback as to which, if any, functions are needed in version 1 and what expressivity should be available to user-defined functions withing R2RML. ]] to solicit community feedback. > * Section 3.1.6 (TableParsing): I am not clear on this one - did it mean table mapped UDF? It looks like implementation detail and should not be part of mapping language requirements? > * Section 3.1.7 (NamedGraph): I am not clear? Do we mean a query can return multiple graphs similar t JDBC returning multiple result sets? Needs clarification, but look this section after clarification needs to move to Section 3.2 as non-core requirements. The SPARQL query language expresses constraints that graph patterns come from particular named graphs¹. This would seem like a core aspect of the expressivity. ¹http://www.w3.org/TR/rdf-sparql-query/#queryDataset > 3. I suggest replacing current hybrid list of editors and authors with two lists: > * Authors: this should refer to all RDB2RDF group members listed in alphabetic order > * Editors: Eric and Michael Happy to do this but I'll wait for someone to second as this is non-editorial. > 4. Finally, in few hours I am traveling in a business trip and I will be back to the Bay Area late Wed. evening. I will miss this Tuesday meeting (regrets). If Eric or Michale can handle this session - thanks. I suggest the team to discuss input from all including the above points. Hope Editors would capture/address the above issues and others, and generate a new version for final review. Let us not rush and go out week or so earlier. > > I will be very busy in this trip and will not be able to respond to emails next week at least a day or so after I come back. > Regards, > > Ahmed > > > Ahmed K. Ezzat, Ph.D. > HP Fellow, Strategic Innovation Architecture Manager, > Business Intelligence Software Division > Hewlett-Packard Corporation > 11000 Wolf Road, Bldg 42 Upper, MS 4502, Cupertino, CA 95014-0691 > Office: Email: Ahmed.Ezzat@hp.com<mailto:Ahmed.Ezzat@hp.com> Off: 408-447-6380 Fax: 1408796-5427 > Personal: Email: AhmedEzzat@aol.com<mailto:AhmedEzzat@aol.com> Tel: 408-253-5062 Fax: 408-253-6271 -- -ericP
Received on Sunday, 9 May 2010 17:56:13 UTC