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  • VOS.VirtSparqlCxmlImport(Last) -- DAVWikiAdmin? , 2017-06-29 07:41:02 Edit WebDAV System Administrator 2017-06-29 02:41:02

    Pivot Collections (Part 5)

    Contents

    Part 1: Introduction

    Part 2: SparqlCxml

    Part 3: SparqlCxml Deep Zoom Collections

    Part 4: PivotViewer

    Part 5: Importing CXML

    Part 6: Facet Pivot Bridge

    Part 7: DETs : Persisting SPARQL Query Results to DAV

    Part 8: Frequently Asked Questions (FAQs)

    Part 9: Glossary


    Importing CXML

    As well as being able to generate CXML from RDF, Virtuoso provides the facility to do the reverse and generate RDF from imported CXML. The sparql_cxml VAD includes the procedure:

    DB.DBA.CXML_TO_RDF_IMPORT_URL (in url varchar)

    Parameters:
    • url : the URL of the CXML file to import

    Usage examples:

    • DB.DBA.CXML_TO_RDF_IMPORT_URL ('http://content.getpivot.com/Collections/uspresidents/uspresidents.cxml');
    • DB.DBA.CXML_TO_RDF_IMPORT_URL ('http://www.bluesware.ch/parlament/collection/Parlament.cxml');
    • DB.DBA.CXML_TO_RDF_IMPORT_URL ('http://pivot.lobsterpot.com.au/Collections/WindowsPhone7Pivot.cxml');
    • DB.DBA.CXML_TO_RDF_IMPORT_URL ('http://pivot.lobsterpot.com.au/collections/PASSChapters.cxml');
    • DB.DBA.CXML_TO_RDF_IMPORT_URL ('http://www.wssdemo.com/livepivot/collections/sharepoint/sharepoint.cxml');

    The given CXML file is imported into a graph of the same name and can be queried like any other. e.g.


    DESCRIBE ?s FROM <http://content.getpivot.com/Collections/uspresidents/uspresidents.cxml> where { ?s ?p ?o }
    
    SELECT * FROM  <http://content.getpivot.com/Collections/uspresidents/uspresidents.cxml> WHERE {?s ?p ?o . ?s virtcxml:FacetImage ?image . }
    
    define input:inference "virtrdf-label"
    DESCRIBE  ?s from <http://pivot.lobsterpot.com.au/collections/PASSChapters.cxml> where { ?s ?p ?o }
    

    Deep Zoom images associated with the collection are also imported into the DZC_xxx tables used to serve DZIs when generating CXML (see VirtSparqlCxmlDzcs). Imported images are assigned to the virtcxml:FacetImage predicate. This can be used directly with the ?image reserved query variable in SELECT statements used for CXML generation. The second DESCRIBE example above exploits inferencing to use the imported images as images for a new dynamic collection. The virtrdf-label inference context includes an entry:


    virtcxml:FacetImage owl:equivalentProperty foaf:depiction
    

    Graph virtcxml: in turn includes an entry:


    foaf:depiction
      a virtcxml:FacetCategoryPattern ;
      virtcxml:FacetType "Item/@virt:Image" ;
      virtcxml:FacetDescription "A facet for absolute URI of depiction of a collection item" .
    

    with the result that imported images associated with virtcxml:FacetImage automatically have a virtcxml:FacetType of "Item/@virt:Image" and are seen by DESCRIBE as candidate images for the dynamic collection.

    Generated Subject URIs

    Each item in the collection receives its own subject URI. The subject URI takes the form: <{collection-URI}#{item-ID}>.

    e.g. Item #2565 in collection http://www.bluesware.ch/parlament/collection/Parlament.cxml


    <Collection Name="Das Schweizer Parlament 2010 (aktualisiert am 6. Dez.2010)" SchemaVersion="1.0">
        <FacetCategories>
            <FacetCategory Name="Funktion" Type="String" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="true"/>
            . . .
        </FacetCategories>
        <Items ImgBase="p_deepzoom\p1.dzc">
            <Item Id="2565" Name="Abate Fabio" Img="#0" Href="http://www.parlament.ch/d/suche/Seiten/biografie.aspx?biografie_id=801">
            . . .
    

    is assigned subject URI <http://www.bluesware.ch/parlament/collection/Parlament.cxml#2565>

    Generated Predicates

    Predicates for Collection and Item Attributes

    Item attributes Href, Description etc are mapped to predicates named virtcxml:Facet{attribute-name}, where:


    prefix virtcxml: <http://www.openlinksw.com/schemas/virtcxml#>
    

    CXML Entity Attribute Mapped to predicate
    Item Href virtcxml:FacetHref
    Item Description virtcxml:FacetDescription
    Item Image virtcxml:FacetImage
    Item Related virtcxml:FacetRelated
    Collection Copyright virtcxml:FacetCopyright

    Rather than just holding an image number, predicate virtcxml:FacetImage holds the full path of the corresponding Deep Zoom image, for example http://www.bluesware.ch/parlament/collection/p_deepzoom/2023.dzi. The image number in the .cxml file is dereferenced through the collection's .dzc file, identified by the Items/@ImgBase attribute, to obtain the DZI path.

    Predicates for Item Facets

    A predicate is generated for each facet category. The predicate URI takes the form virtcxml:Custom-{facet-category-name} e.g. A collection containing the following facet categories:


    <Collection Name="Das Schweizer Parlament 2010 (aktualisiert am 6. Dez.2010)" SchemaVersion="1.0">
    <FacetCategories>
    <FacetCategory Name="Alter" Type="Number" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="false"/>
    <FacetCategory Name="Amtsjahre" Type="Number" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="false"/>
    <FacetCategory Name="Funktion" Type="String" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="true"/>
    <FacetCategory Name="Geburtsdatum" Type="DateTime" Format="dd. MMM. yyyy" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="false"/>
    <FacetCategory Name="Geschlecht" Type="String" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="true"/>
    <FacetCategory Name="Kanton" Type="String" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="true"/>
    <FacetCategory Name="Kinder" Type="Number" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="false"/>
    <FacetCategory Name="Parlamentsmandate" Type="Number" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="false"/>
    <FacetCategory Name="Partei" Type="String" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="true"/>
    <FacetCategory Name="Vorname" Type="String" p:IsFilterVisible="true" p:IsMetaDataVisible="true" p:IsWordWheelVisible="true"/>
    </FacetCategories>
    ...
    

    when imported, generates the predicates:


    http://www.openlinksw.com/schemas/virtcxml#Custom-Alter
    http://www.openlinksw.com/schemas/virtcxml#Custom-Amtsjahre
    http://www.openlinksw.com/schemas/virtcxml#Custom-Funktion
    http://www.openlinksw.com/schemas/virtcxml#Custom-Geburtsdatum
    http://www.openlinksw.com/schemas/virtcxml#Custom-Geschlecht
    http://www.openlinksw.com/schemas/virtcxml#Custom-Kanton
    http://www.openlinksw.com/schemas/virtcxml#Custom-Kinder
    http://www.openlinksw.com/schemas/virtcxml#Custom-Parlamentsmandate
    http://www.openlinksw.com/schemas/virtcxml#Custom-Partei
    http://www.openlinksw.com/schemas/virtcxml#Custom-Vorname
    

    Converting Generated Predicates to Common Predicates

    Following a CXML import, some of the generated predicates can be converted to more popular predicates using the Virtuoso/PL procedure DB.DBA.CXML_FACETS_TO_COMMON_PREDS. The affected predicates are detailed below:

    Generated Predicate Converted To
    virtcxml:FacetName rdfs:label
    virtcxml:FacetDescription dc:description
    virtcxml:FacetHref sioc:links_to
    virtcxml:FacetImage foaf:depiction
    Usage Example:

    sparql clear graph <http://qq/1>;
    sparql insert in <http://qq/1> { ?s ?p ?o } from <http://content.getpivot.com/Collections/uspresidents/uspresidents.cxml> where {?s ?p ?o};
    DB.DBA.CXML_FACETS_TO_COMMON_PREDS ('http://qq/1');