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Re: RDB2RDF WG agenda for 2010-10-05 meeting 1600 UTC

From: Seema Sundara <seema.sundara@oracle.com>
Date: Tue, 05 Oct 2010 12:03:20 -0400
Message-ID: <4CAB4C48.80903@oracle.com>
To: RDB2RDF WG <public-rdb2rdf-wg@w3.org>
Seema Sundara wrote:
> Attached is the latest (5 Oct  2010) version of the FPWD that includes 
> an example.
>
> Thanks
> Seema & Souri.
>
> Souripriya Das wrote:
>> I have attached a draft for the FPWD that Seema and I have prepared. 
>> It is an html document.
>> Please take a look if you get a chance. We are still working on it.
>>
>> We hope to discuss this in our upcoming telcon.
>>
>> Thanks,
>> - Souri.
>>
>> On 10/1/2010 2:01 PM, Souripriya Das wrote:
>>> We have filled the initial portions of a W3C Working Draft template 
>>> and at the moment working on putting the real content (the Schema 
>>> and a (running) example). -- Souri.
>>>
>>> On 10/1/2010 11:06 AM, Michael Hausenblas wrote:
>>>> All,
>>>>
>>>> Below the agenda for our next week's meeting mainly discussing the 
>>>> FPWD
>>>> "Relational Database to RDF Mapping Language" - Souri, Seema, and 
>>>> Richard,
>>>> what's the status, there?
>>>>
>>>> Cheers,
>>>>        Michael
>>>>
>>>> ---------------------------------------------------------
>>>> AGENDA Teleconference
>>>> W3C RDB2RDF Working Group telephone conference 2010-10-05
>>>> ----------------------------------------------------------
>>>> Tuesday, 5 October *16:00-17:00 UTC* Local time:
>>>> http://www.timeanddate.com/worldclock/fixedtime.html?month=10&day=05&year=20 
>>>>
>>>> 10&hour=16&min=00&sec=0
>>>> Bridge US: +1-617-761-6200 (Zakim) Conference code : 7322733# (spells
>>>> "RDB2RDF")
>>>> Duration : 60 minutes
>>>> -------------------------------------------------------------------
>>>> IRC channel : #RDB2RDF on irc.w3.org:6665 W3C IRC Web Client :
>>>> http://www.w3.org/2001/01/cgi-irc
>>>> Zakim information : http://www.w3.org/2002/01/UsingZakim
>>>> Zakim bridge monitor : http://www.w3.org/1998/12/bridge/Zakim.html
>>>> Zakim IRC bot : http://www.w3.org/2001/12/zakim-irc-bot.html
>>>> -------------------------------------------------------------------
>>>>
>>>> Chair: Michael
>>>> Scribe: Zakim, pick a victim
>>>>
>>>>
>>>> 1. Admin
>>>> PROPOSAL: Accept the minutes of last meeting, see
>>>> http://www.w3.org/2010/09/28-rdb2rdf-minutes.html
>>>>
>>>> Review open actions, see
>>>> http://www.w3.org/2001/sw/rdb2rdf/track/actions/open
>>>>
>>>> 2. FPWD "Relational Database to RDF Mapping Language"
>>>> The editors (Souri, Seema, and Richard) will present the first draft.
>>>>
>>>> 3. Default Mapping Cases
>>>> http://www.w3.org/2001/sw/rdb2rdf/wiki/All_Cases_for_Default_Mapping
>>>>
>>>> 4. AOB
>>>>
>>>>
>>>> Cheers,
>>>>        Michael
>>>>
>>>
>>>
>>
>>
>> ------------------------------------------------------------------------
>
>
> ------------------------------------------------------------------------
>
> W3C <http://www.w3.org/>
>
>
>   R2RML: RDB2RDF Mapping Language
>
>
>     W3C Working Draft 5 October 2010
>
> This version:
>
> URL-to-be-created
> Editors:
>     Souripriya Das, Oracle
>     Seema Sundara, Oracle
>     Richard Cyganiak, DERI, National University of Ireland, Galway,
>     Ireland <richard@cyganiak.de> <mailto:richard@cyganiak.de>
>
> ------------------------------------------------------------------------
>
>
>     Abstract
>
> RDF is a directed, labeled graph data format for representing 
> information in the Web. This specification defines the syntax and 
> semantics of the R2RML (RDB2RDF Mapping Language) for translating 
> Relational data to RDF.
>
>
>     Status of this Document
>
> /This section describes the status of this document at the time of its 
> publication. Other documents may supersede this document. A list of 
> current W3C publications and the latest revision of this technical 
> report can be found in the //W3C technical reports index 
> <http://www.w3.org/TR/> at http://www.w3.org/TR/./
>
> Publication as a Working Draft does not imply endorsement by the W3C 
> Membership. This is a draft document and may be updated, replaced or 
> obsoleted by other documents at any time. It is inappropriate to cite 
> this document as other than work in progress.
>
> The documents produced by this Working Group are:
>
>     * R2RML: RDB2RDF Mapping Language (this document)
>
> This publication includes the RDF Schema that can be used to specify a 
> mapping of relational data to RDF. The structure of this document will 
> change based upon future decisions taken by the W3C RDB2RDF Working Group.
>
> Comments on this document should be sent to 
> public-rdb2rdf-comments@w3.org 
> <mailto:public-rdb2rdf-comments@w3.org>, a mailing list with a public 
> archive <http://lists.w3.org/Archives/Public/public-rdb2rdf-comments>.
>
> This document was produced by the RDB2RDF Working Group 
> <http://www.w3.org/2001/sw/RDB2RDF/>, which is part of the W3C 
> Semantic Web Activity <http://www.w3.org/2001/sw/Activity>.
>
> This document was produced by a group operating under the 5 February 
> 2004 W3C Patent Policy 
> <http://www.w3.org/Consortium/Patent-Policy-20040205/>. W3C maintains 
> a public list of any patent disclosures 
> <http://www.w3.org/2004/01/pp-impl/35463/status> made in connection 
> with the deliverables of the group; that page also includes 
> instructions for disclosing a patent. An individual who has actual 
> knowledge of a patent which the individual believes contains Essential 
> Claim(s) 
> <http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential> 
> must disclose the information in accordance with section 6 of the W3C 
> Patent Policy 
> <http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure>.
>
>
>     Table of Contents
>
> 1 Introduction <#introduction>
>     1.1 Document Outline <#docOutline>
>     1.2 Document Conventions <#docConventions>
>         1.2.1 Namespaces <#docNamespaces>
>         1.2.2 Data Descriptions <#docDataDesc>
>         1.2.3 Terminology <#docTerminology>
> 2 Overview <#R2rmlOverview>
> 3 RDF Schema for R2RML <#R2rmlSchema>
>     3.1 RDFTermMap Class <#RDFTermMap_Class>
>         3.1.1 Properties of the RDFTermMap Class 
> <#RDFTermMap_Properties>
>             3.1.1.1 rr:property 
> <#RDFTermMap_property_Property>
>             3.1.1.2 rr:column <#RDFTermMap_column_Property>
>             3.1.1.3 rr:inverseExpression 
> <#RDFTermMap_inverseExpression_Property>
>             3.1.1.4 rr:datatype 
> <#RDFTermMap_datatype_Property>
>             3.1.1.5 rr:language 
> <#RDFTermMap_language_Property>
>             3.1.1.6 rr:columnGraph 
> <#RDFTermMap_columnGraph_Property>
>             3.1.1.7 rr:constantValue 
> <#RDFTermMap_constantValue_Property>
>             3.1.1.8 rr:isRDFType 
> <#RDFTermMap_isRDFType_Property>
>             3.1.1.9 rr:isComputed 
> <#RDFTermMap_isComputed_Property>
>     3.2 Subclasses of RDFTermMap Class <#RDFTermMap_Subclasses>
>         3.2.1 RDFSubjectTermMap Class <#RDFSubjectTerm>
>         3.2.2 IRIMap Class <#RDFIRI>
>         3.2.3 bNodeMap Class <#RDFBNODE>
>         3.2.4 LiteralMap Class <#RDFLiteral>
>     3.3 Table2TriplesMap Class <#Table2TriplesMap_Class>
>         3.3.1 Properties of the Table2TriplesMap Class 
> <#Table2TriplesMap_Properties>
>             3.3.1.1 rr:logicalTable 
> <#T2TMap_logicalTable_Property>
>             3.3.1.2 rr:class <#T2TMap_class_Property>
>             3.3.1.3 rr:tableGraphMap 
> <#T2TMap_tableGraphMap_Property>
>             3.3.1.4 rr:subjectMap 
> <#T2TMap_subjectMap_Property>
>             3.3.1.5 rr:propertyObjectMap 
> <#T2TMap_propertyObjectMap_Property>
>             3.3.1.6 rr:computedPropertyMap 
> <#T2TMap_computedPropertyMap_Property>
>             3.1.1.7 rr:rowGraphPropertyMap 
> <#T2TMap_rowGraphPropertyMap_Property>
>             3.1.1.8 rr:foreignKeyMap 
> <#T2TMap_foreignKeyMap_Property>
>     3.4 ForeignKey Class <#ForeignKey_Class>
>         3.4.1 Properties of the ForeignKey Class 
> <#ForeignKey_Properties>
>             3.4.1.1 rr:key <#ForeignKey_key_Property>
>             3.4.1.2 rr:parentTable2TriplesMap 
> <#ForeignKey_parentTable2TriplesMap_Property>
>             3.4.1.3 rr:joinCondition 
> <#ForeignKey_joinCondition_Property>
>
>
>       Appendices
>
> A References <#sec-bibliography>
>     A.1 Normative References <#sec-normative-refs>
>     A.2 Other References <#sec-non-normative-refs>
> B Example of SQL based RDB2RDF Mapping using the Turtle Syntax 
> <#sec-example>
>     B.1 Sample Relational Tables <#sec-tables>
>     B.2 Mapping Specification for the Tables <#sec-mapping>
>         B.2.1 Mapping Specification for the DEPT Table 
> <#sec-depttable_mapping>
>         B.2.2 Mapping Specification for the EMP Table 
> <#sec-emptable_mapping>
>         B.2.3 Mapping Specification for the LIKES Table 
> <#sec-likestable_mapping>
> C CVS History <#sec-cvsLog>
>
> ------------------------------------------------------------------------
>
>
>     1 Introduction
>
> RDF is a directed, labeled graph data format for representing 
> information in the Web. RDF is often used to represent, among other 
> things, personal information, social networks, metadata about digital 
> artifacts, as well as to provide a means of integration over disparate 
> sources of information. The ability to view realtional data as RDF 
> will allow integration of relational data from disparate sources. This 
> specification defines the schema for mapping relational data to RDF 
> using Turtle syntax.
>
> The R2RML language for mapping relational data to RDF is designed to 
> meet the use cases and requirements identified by the RDB2RDF Working 
> Group in Use Cases and Requirements 
> [http://www.w3.org/2001/sw/rdb2rdf/wiki/Use_Cases_and_Requirements].
>
>
>       1.1 Document Outline
>
> Unless otherwise noted in the section heading, all sections and 
> appendices in this document are normative.
>
> /@@Revise when structure stable/
>
> This section of the document, section 1 <#introduction>, introduces 
> the R2RML specification. It presents the organization of this 
> specification document and the conventions used throughout the 
> specification.
>
> Section 3 <#R2rmlSchema> presents details of the RDFS schema for R2RML.
>
>
>       1.2 Document Conventions
>
>
>         1.2.1 Namespaces
>
> In this document, examples assume the following namespace prefix 
> bindings unless otherwise stated:
>
> Prefix 	IRI
> |rdf:| 	|http://www.w3.org/1999/02/22-rdf-syntax-ns#|
> |rdfs:| 	|http://www.w3.org/2000/01/rdf-schema#|
> |xsd:| 	|http://www.w3.org/2001/XMLSchema#|
> |rr:| 	|http://www.w3.org/ns/r2rml#|
> |xyz:| 	|http://xyz.com/example#|
>
>
>         1.2.2 Data Descriptions
>
> This document uses the Turtle 
> <http://www.w3.org/TeamSubmission/turtle/> [TURTLE <#TURTLE>] data 
> format to show each triple explicitly. Turtle allows IRIs to be 
> abbreviated with prefixes:
>
> @prefix dc:   <http://purl.org/dc/elements/1.1/> .
> @prefix :     <http://example.org/book/> .
> :book1  dc:title  "R2RML Tutorial" .
>
>
>         1.2.3 Terminology
>
> The R2RML language includes IRIs, a subset of RDF URI References that 
> omits spaces.
>
> The following terms are defined in RDF Concepts and Abstract Syntax 
> <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/> [CONCEPTS] 
> <#CONCEPTS> and used in R2RML:
>
>     * IRI
>       <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-URI-reference>
>       (corresponds to the Concepts and Abstract Syntax term "|RDF URI
>       reference|")
>     * literal
>       <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-literal>
>     * lexical form <http://www.w3.org/TR/rdf-concepts/#dfn-lexical-form>
>     * plain literal
>       <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-plain-literal>
>     * language tag
>       <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-language-identifier>
>     * typed literal
>       <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-typed-literal>
>     * datatype IRI
>       <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-datatype-URI>
>       (corresponds to the Concepts and Abstract Syntax term "|datatype
>       URI|")
>     * blank node
>       <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-blank-node>
>
>
>     2 Overview
>
> The overall flow for mapping relational data to RDF may be summarized 
> as follows:
>
> Given read-only access to a set of tables and/or views in a database, 
> one can write a mapping of the content of some or all of these tables 
> or views or any logical tables formed as SQL queries involving some of 
> these tables and/or views to generate corresponding RDF triples. 
> Besides generating triples, the mapping may also create an RDFS schema 
> consisting of RDFS classes and RDF properties and RDF named graphs may 
> be created for holding subsets of the generated triples.
>
> Note that the RDF triples may not actually be physically generated and 
> instead the mapping may only allow the relational data to be viewed as 
> RDF triples.
>
> The RDB2RDF Mapping Language, R2RML, described in this document, 
> allows one to write a mapping to (virtually) generate a custom 
> collection RDF graphs, named or unnamed, containing RDF triples, from 
> a set of relational tables and/or views to which the user has (at 
> least) read-only access.
>
>
>     3 RDF Schema for R2RML using Turtle Syntax
>
> This section describes the RDF Schema that can be used for specifying 
> mapping from a relational schema to RDF.
>
>
>       3.1 RDFTermMap Class
>
> The RDFTermMap class reprersents the description of mapping to any RDF 
> term: IRIs, blank nodes, or literals. This has two main components: 
> mapping to an RDF property and mapping to an object value (to be 
> associated with the property).
>
>
>         3.1.1 Properties of the RDFTermMap Class
>
> This section defines the RDF properties that have the RDFTermMap class 
> as their domain.
>
>
>           3.1.1.1 rr:property property
>
> rr:property rdfs:range rdf:Resource .
>
> This property specifies the RDF property component of the RDFTermMap 
> instance.
>
>
>           3.1.1.2 rr:column property
>
> rr:column rdfs:range xsd:string .
>
> This property specifies the object value component of the RDFTermMap 
> instance. Specifically, the column name of the logical table that will 
> be used for obtaining the object value.
>
>
>           3.1.1.3 rr:inverseExpression property
>
> rr:inverseExpression rdfs:range xsd:string .
>
> This optional property specifies an expression that allows, at query 
> processing time, use of indexes on any (underlying) relational table 
> when accessing based on a value of a column (defined as an expression) 
> in the logical table.
>
> For example, for the deptId column in the logical table shown in 
> Section 3.3.1.1, the inverse expression could be defined as follows:
>
> "{alias.}deptno = substr({alias.}deptId,length('dept')+1)"
>
> to facilitate use of an index on the deptno column of the dept table. 
> Note that the actual alias (say d) used for the dept table is used to 
> expand {alias.} (to d.).
>
>
>           3.1.1.4 rr:datatype property
>
> rr:datatype rdfs:range rdf:Resource .
>
> This property specifies the datatype for the object value component of 
> the RDFTermMap instance.
>
>
>           3.1.1.5 rr:language property
>
> rr:language rdfs:range xsd:string .
>
> This property specifies the language for the object value component of 
> the RDFTermMap instance. This property is applicable only if the 
> datatype of the object value is of type xsd:string.
>
>
>           3.1.1.6 rr:columnGraph property
>
> rr:columnGraph rdfs:range rr:SubjectTermMap .
>
> This property specifies the RDF named graph for the triples that is 
> constructed with the (property, object) pair of the RDFTermMap.
>
>
>           3.1.1.7 rr:constantValue property
>
> rr:constantValue rdfs:range xsd:string .
>
> This property specifies the optional constant value for the object 
> component of the RDFTermMap instance.
>
>
>           3.1.1.8 rr:isRDFType property
>
> rr:isRDFType rdfs:range xsd:boolean .
>
> This property specifies if the object value component of the 
> RDFTermMap instance is also a value for the rdf:type property.
>
>
>           3.1.1.9 rr:isComputed property
>
> rr:isComputed rdfs:range xsd:boolean .
>
> This property specifies if the object value component of the 
> RDFTermMap instance is a computed property.
>
>
>       3.2 Subclasses of the RDFTermMap Class
>
> This section enumerates the subclasses of the RDFTermMap class. These 
> classes describe the various types of RDF terms namely IRIs, blank 
> nodes, and literals.
>
>
>         3.2.1 RDFSubjectTermMap
>
> The RDFSubjectTermMap class represents the mapping to any RDF term 
> that can appear as subject of an RDF triple: IRIs or blank nodes.
>
> rr:RDFSubjectTermMap rdfs:subClassOf rr:RDFTermMap .
>
>
>         3.2.2 IRIMap
>
> The IRIMap class represents the mapping to a RDF Resource.
>
> rr:IRIMap rdfs:subClassOf rr:RDFSubjectTermMap .
>
>
>         3.2.3 bNodeMap
>
> The bNodeMap class represents the mapping to a RDF blank node.
>
> rr:bNodeMap rdfs:subClassOf rr:RDFSubjectTermMap .
>
>
>         3.2.4 LiteralMap
>
> The LiteralMap class represents the mapping to a RDF literal.
>
> rr:LiteralMap rdfs:subClassOf rr:RDFTermMap .
>
>
>       3.3 The Table2TriplesMap Class
>
> Table2TriplesMap is an RDFS class that allows specification of a 
> mapping of the rows in a logical table, represented by a SQL query, or 
> the name of a table or view and its owner, into RDF triples. 
> Properties of a Table2TriplesMap instance allows specification of 
> various aspects of the mapping such as, mapping of (some of) the 
> columns in the logical table to RDF properties, name of the RDF 
> graph(s) that would store the RDF triples, and so on.
>
>
>         3.3.1 Properties of the Table2TriplesMap Class
>
> This section defines the RDF properties that have the Table2TriplesMap 
> class as their domain.
>
>
>           3.3.1.1 rr:logicalTable property
>
> rr:logicalTable rdfs:range xsd:String .
>
> This property specifies the logical table (i.e., a SQL query or a 
> table or view name plus its owner name) whose rows are mapped to RDF 
> triples by this Table2TriplesMap instance. Note that each row in the 
> logical table is identified as a resource and is used as the subject 
> for the RDF triples.
>
> The following example speifies that the Table2TriplesMap instance 
> Table2TriplesMap1 maps the rows in the logical table defined by the 
> SQL string to RDF triples.
>
> <#Table2TriplesMap1> rr:logicalTable 
>                                 """Select 'dept' || deptno AS deptId
>                                         , deptno
>                                         , dname
>                                         , loc
>                                    from dept""" .
>
> The cardinality of this property, for a Table2TriplesMap instance, 
> must be exactly 1. That is, a Table2TriplesMap instance must have 
> exactly one value for this property.
>
>
>           3.3.1.2 rr:class property
>
> rr:class rdfs:range rdfs:Class .
>
> This property specifies the RDFS class associated with a 
> Table2TriplesMap instance. In the generated RDF data, resource 
> corresponding to each row in the logical table is an instance of this 
> RDFS class.
>
> In the following example, Table2TriplesMap1 is associated with the the 
> RDFS class xyz:dept using rr:class. This leads to creation of xyz:dept 
> as an RDFS class in the RDFS schema generated from the mapping 
> specification and in the generated RDF data, RDF resource 
> corresponding to each row in the logical table associated with 
> Table2TriplesMap1 is an instance of the xyz:dept class.
> [@@ We need to discuss this to make it optional to generate xyz:dept 
> as an RDFS class in the generated RDFS schema.]
>
> <#Table2TriplesMap1> rr:class xyz:dept .
>
>
>           3.3.1.3 rr:tableGraphMap property
>
> rr:tableGraphMap rdfs:range rdf:Resource .
>
> This property specifies the graph (IRI or blank node) that would 
> contain all the RDF triples in a Table2TriplesMap instance.
>
> In the following example, all the RDF triples in Table2TriplesMap1 
> would be stored in the RDF named graph xyz:DeptGraph.
>
> <#Table2TriplesMap1> rr:tableGraphMap xyz:DeptGraph .
>
>
>           3.3.1.4 rr:subjectMap property
>
> rr:subjectMap  rdfs:range rr:RDFSubjectTermMap .
>
> This property specifies the mapping to obtain the IRI or blank node 
> that is used as the subject of /all/ the RDF triples generated from 
> /one/ row of the table.
>
>
>           3.3.1.5 rr:propertyObjectMap property
>
> rr:propertyObjectMap rdfs:range rr:RDFTermMap .
>
> This property specifies the mapping to obtain the (property, object) 
> pair for each RDF triple corresponding to a column and its values in 
> the table.
>
>
>           3.3.1.6 rr:computedPropertyMap property
>
> rr:computedPropertyMap rdfs:range rr:IRIMap .
>
> This property specifies the mapping to obtain the property IRIs from a 
> column in the table. This mapping also contains a property name that 
> identifies this computedPropertyMap and this property name is used in 
> a rr:propertyObjectMap to form the association. The property IRI 
> generated (from the column identified in the rr:computedPropertyMap) 
> for each row, along with the value of the column identified in the 
> rr:propertyObjectMap, are used to create the (property, object) pairs.
>
>
>           3.3.1.7 rr:rowGraphPropertyMap property
>
> rr:rowGraphPropertyMap rdfs:range rr:SubjectTermMap .
>
> This property specifies the mapping to obtain the IRI or blank node 
> that identifies the RDF named graph for all the RDF triples generated 
> from one row in the table. The minimum cardinality for this property 
> is zero and no restriction on maximum cardinality. If for a row, the 
> generated graph IRI or blank node label is NULL, then the triples 
> generated from that row go to an unnamed graph.
>
>
>           3.3.1.8 rr:foreignKeyMap property
>
> rr:foreignKeyMap rdfs:range rr:ForeignKey .
>
> This property specifies the mapping to obtain the property, and a join 
> condition that can be used to retrieve the object (from the parent 
> Table2Triples instance), for the generated RDF triple. This property 
> would typically correspond to a foreign key definition in the table.
>
>
>       3.4 The ForeignKey Class
>
> ForeignKey is an RDFS class that allows specification of the mapping 
> that describes a foreign key relationship.
>
> rr:ForeignKey a rdfs:Class .
>
> This class has three components: a key that specifies the column 
> constituting the constraint in the child table, the Table2TripleMap 
> corresponding to the parent table, and the join condition 
> corresponding to the foreign key constraint.
>
>
>         3.4.1 Properties of the ForeignKey Class
>
> This section defines the RDF properties that have the ForeignKey class 
> as their domain.
>
>
>           3.4.1.1 rr:key property
>
> rr:key rdfs:range rdf:Resource .
>
> This property specifies the key component of the ForeignKey instance.
>
>
>           3.4.1.2 rr:parentTable2TriplesMap property
>
> rr:parentTable2TriplesMap rdfs:range rr:Table2TriplesMap .
>
> This property specifies the Table2TriplesMap corresponding to the 
> parent table component, of the ForeignKey instance.
>
>
>           3.4.1.3 rr:joinCondition property
>
> rr:joinCondition rdfs:range xsd:string .
>
> This property specifies the join condition of the ForeignKey instance.
>
>
>     A References
>
>
>       A.1 Normative References
>
>
>       A.2 Other References
>
>
>     B Example of SQL based RDB2RDF Mapping using the Turtle Syntax
>
> In this section we show an example relational schema and then map the 
> example schema to RDF using the Turtle syntax.
>
>
>       B.1 Sample Relational Tables
>
> We illustrate our example with the use of the following three 
> relational tables
>
>
>         B.1.1 DEPT Table
>
> Column Name 	Column Datatype 	Column Key Constraints
> |deptno| 	|NUMBER| 	|UNIQUE|
> |dname| 	|VARCHAR2(30)|
> |loc| 	|VARCHAR2(100)|
>
>
>         B.1.2 EMP Table
>
> Column Name 	Column Datatype 	Column Key Constraint
> |empno| 	|NUMBER| 	|PRIMARY KEY|
> |ename| 	|VARCHAR2(100)|
> |job| 	|VARCHAR2(30)|
> |deptno| 	|NUMBER| 	|REFERENCES DEPT(deptno)|
> |etype| 	|VARCHAR2(30)|
>
>
>         B.1.3 LIKES Table
>
> Column Name 	Column Datatype 	Column Key Constraint
> |id| 	|VARCHAR2(4000)|
> |likeType| 	|VARCHAR2(30)|
> |likedObj| 	|VARCHAR2(100)|
>
>
>       B.2 Mapping Specification for the Tables
>
> The tables specified in the above section are mapped to the RDF using 
> the mapping specificied in this document. In addition to the prefix 
> conventions specified in Section 1.2.1 Namespaces <#docNamespaces>
> , we also use the following prefixes in our example:
>
> Prefix 	IRI
> |emp:| 	|http://www.example.com/emp#|
> |dept:| 	|http://www.example.com/dept#|
> |likes:| 	|http://www.example.com/likes#|
>
>
>         B.2.1 Mapping Specification for the DEPT Table
>
> <#Table2TriplesMap1>
>     a rr:Table2TriplesMap;
>     rr:logicalTable """
>        Select 'dept' || deptno AS deptId
>             , deptno
>             , dname
>             , loc
>          from dept
>       """;
> 		rr:class xyz:dept;
>     rr:tableGraphMap xyz:DeptGraph;
>     rr:subjectMap [ a rr:bNodeMap; rr:column "deptId";
>                     rr:InverseExpression "(alias.)deptno = substr({alias.}deptId,length('dept')+1)"];
>     rr:propertyObjectMap [ a rr:LiteralMap; rr:datatype xsd:positiveInteger;
>                            rr:property dept:deptno; rr:column "deptno" ];
>     rr:propertyObjectMap [ rr:property dept:name; rr:column "dname" ];
>     rr:propertyObjectMap [ rr:property dept:location; rr:column "loc" ];
>     rr:propertyObjectMap [ rr:property dept:COMPANY; rr:constantValue "XYZ Corporation" ];
> 		.
>
>
>         B.2.2 Mapping Specification for the EMP Table
>
> <#Table2TriplesMap2>
>     a rr:Table2TriplesMap;
>     rr:logicalTable """
>        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
>        """;
> 		rr:class xyz:emp;
>     rr:subjectMap [ a rr:IRIMap; rr:column "empURI" ];
> 		
>     rr:rowGraphPropertyMap [ rr:column "graphURI"; a rr:IRIMap];
> 		
>     rr:propertyObjectMap [ rr:property emp:jobtype; rr:column "jobTypeURI"; rr:isRDFType "true"^^xsd:boolean];
>     rr:propertyObjectMap [ rr:property emp:emptype; rr:column "empTypeURI"; rr:isRDFType "true"^^xsd:boolean];
> 		
>     rr:propertyObjectMap [ rr:property emp:empno; rr:column "empno" ];
>     rr:propertyObjectMap [ rr:property emp:name; rr:column "ename"; rr:columnGraph [ rr:constantValue "emp:empNameGraph"; a rr:IRIMap]];
>     rr:propertyObjectMap [ rr:property emp:job; rr:column "job" ];
>     rr:propertyObjectMap [ rr:property emp:deptNum; rr:column "deptno" ];
>     rr:propertyObjectMap [ rr:property emp:etype; rr:column "etype" ];
>     rr:foreignKeyMap [
>       rr:key emp:c_ref_deptno;
>       rr:parentTable2TriplesMap xyz:dept;
>       rr:joinCondition "{child.}deptno = {parent.}deptno";
>     ];
>     .
>
>
>         B.2.3 Mapping Specification for the LIKES Table
>
> <#Table2TriplesMap3>
>     a rr:Table2TriplesMap;
>     rr:logicalTable """
>       Select id
>            , likeType
>            , likedObj
>         from likes
>       """;
> 		rr:class xyz:likes;
>     rr:tableGraphMap xyz:LikesGraph;
>     rr:subjectMap [ a rr:IRIMap; rr:column "id"];
>     rr:ComputedPropertyMap [ rr:property likes:likeType; rr:column "likeType" ];
>     rr:propertyObjectMap [ rr:property likes:likeType; rr:column "likedObj"; rr:isComputed "true"^^xsd:boolean];
>     .
>
>
>     C CVS History
>
> $Log: Overview.html,v $
>
> Revision 1.1  2010/09/29 15:27:28  sdas2/ssundara
> CREATED
>
>
Received on Tuesday, 5 October 2010 16:05:21 UTC

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