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  • VOS.VOSSQL2RDFMappingExample(Last) -- DAVWikiAdmin? , 2017-06-13 05:47:18 Edit WebDAV System Administrator 2017-06-13 05:47:18

    Mapping Example

    This example follows in an excerpt from an actual mapping of the phpBB3 SQL schema to the classes defined by the SIOC and FOAF ontologies:

    -- SPARQL keyword which is the SPARQL cue for the SQL processor
    -- PREFIX declarations
    PREFIX  sioc:  <http://rdfs.org/sioc/ns#>
    PREFIX  sioct: <http://rdfs.org/sioc/types#>
    PREFIX  atom:  <http://atomowl.org/ontologies/atomrdf#>
    PREFIX  rdfs:  <http://www.w3.org/2000/01/rdf-schema#>
    PREFIX  foaf:  <http://xmlns.com/foaf/0.1/>
    PREFIX  dc:    <http://purl.org/dc/elements/1.1/>
    PREFIX  dct:   <http://purl.org/dc/terms/>
    PREFIX  skos:  <http://www.w3.org/2004/02/skos/core#>
    PREFIX  geo:   <http://www.w3.org/2003/01/geo/wgs84_pos#>
    PREFIX  bm:    <http://www.w3.org/2002/01/bookmark#>
    PREFIX  exif:  <http://www.w3.org/2003/12/exif/ns/>
    PREFIX  ann:   <http://www.w3.org/2000/10/annotation-ns#>
    PREFIX  phpbb: <http://openlinksw.com/phpBB3/>
    -- Remove prior mappings 
    DROP QUAD MAP GRAPH IRI ("http://^{URIQADefaultHost}^/phpBB3_v/") .
    -- Declare the special Virtuoso-URI-Generator functions for later use in actual mappings
    CREATE IRI CLASS  phpbb:site_iri     
        ( IN  dummy       VARCHAR NOT NULL ) .
    CREATE IRI CLASS  phpbb:user_iri
        ( IN  user_name   INTEGER NOT NULL ) .
    CREATE IRI CLASS  phpbb:usergroup_iri
        ( IN  group_name  INTEGER NOT NULL ) .
    CREATE IRI CLASS  phpbb:forum_iri
        ( IN  forum_id    INTEGER NOT NULL ) .
    CREATE IRI CLASS  phpbb:post_iri
        ( IN  post_id     INTEGER NOT NULL ) .
    -- Start the actual mapping declaration process
    -- Identify Quad Storage Partition within Quad Store
    ALTER QUAD STORAGE virtrdf:DefaultQuadStorage
    -- Declare Named Graph URI / IRI associated with previously declared Quad Storage partition
        CREATE virtrdf:phpBB3 AS GRAPH IRI ("http://^{URIQADefaultHost}^/phpBB3_v/")
    -- Use SPARQL / Turtle Graph patterns to declare:
    -- mappings between Table and a RDF Schema or Ontology Class
       # Default phpBB Space
       phpbb:site_iri (PHPBB3.phpBB.phpBB3_site_rdf.WS_DUMMY)
       a sioc:Space ;
    --- mappings between Columns in a Table with Attributes of a RDF Schema or Ontology Class
       dc:title WEB_TITLE .
    -- The combined data from each mapped column (row) is used to generate an instance (Entity/Individual) of this RDF Schema or Ontology Class 
    -- Repeat the process for Each Table being mapped
       # User
       phpbb:user_iri (PHPBB3.phpBB.phpBB3_users_rdf.username)
         a                sioc:User ;
         sioc:id          user_id ;
         sioc:name        username ;
         sioc:email       E_MAIL ;
         sioc:email_sha1  E_MAIL_SHA1 ;
         sioc:has_space   phpbb:site_iri(WS_DUMMY) .
       # Usergroup
       phpbb:usergroup_iri (PHPBB3.phpBB.phpBB3_usergroups_rdf.group_name)
         a          sioc:Usergroup ;
         sioc:id    group_id ;
         sioc:name  group_name .