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  • OATWikiWeb.InteractiveSparqlQueryBuilderQueryTutorial(Last) -- Owiki? , 2016-08-19 14:58:44 Edit owiki 2016-08-19 14:58:44

    iSPARQL Querying Tutorial with SPARQL Query type "SELECT".

    This tutorial shows how to execute a SPARQL query with type "SELECT". You can find a rich list of Virtuoso SPARQL Queries in the References section.

    Enter and execute a query

    Choose a SPARQL query from the References list. For this example, let's use the SPARQL query, which dumps all Weblog Posts for the ODS Member "demo". You can find this SPARQL Query in either the ODS SPARQL Queries or the ODS Weblog SPARQL Queries list.

    PREFIX    rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 
    PREFIX   sioc:  <http://rdfs.org/sioc/ns#> 
    PREFIX  sioct:  <http://rdfs.org/sioc/types#>
    PREFIX    xsd:  <http://www.w3.org/2001/XMLSchema#> 
    PREFIX    dct:  <http://purl.org/dc/elements/1.1/>
    PREFIX    dcc:  <http://purl.org/dc/terms/>
    SELECT DISTINCT  ?forum_name
                     ?post
                     ?title
                     ?cr
                     ?url 
    FROM <http://demo.openlinksw.com/dataspace> 
    WHERE
      { 
        ?forum  a                  sioct:Weblog                                      .
        ?forum  sioc:id            ?forum_name                                       .
        ?forum  sioc:scope_of      ?role                                             .
        ?role   sioc:function_of   <http://demo.openlinksw.com/dataspace/demo#this>  .
        ?forum  sioc:container_of  ?post                                             . 
        OPTIONAL { ?post  dct:title    ?title }  .
        OPTIONAL { ?post  dcc:created  ?cr    }  .
        OPTIONAL { ?post  sioc:link    ?url   }  .
      }
    ORDER BY DESC (?cr)
    
    1. Go to iSPARQL demo page.
    2. By default, user name demo and password demo should be shown in the Login form. Click OK.



    3. You will now see the iSPARQL home page, with QBE tab open and default graph elements on the Canvas. Click the Clear Pane icon on the toolbar to empty the Canvas.



    4. Change the Data Source URI field value on the QBE tab to the Graph of the database against which you want to execute your query, i.e., for this example -- http://demo.openlinksw.com/dataspace



    5. Click the Advanced tab.
    6. Change the Graph value to also be http://demo.openlinksw.com/dataspace, and enter (copy-and-paste) the query chosen above into the SPARQL Query text-area:



    7. Click the Run Query button on the Advanced tab.
    8. The Result sub-tab shown below the Advanced SPARQL Query Working Canvas will present the results of executing our SPARQL Query, by default in Human readable format.



    9. Change the results table column widths by dragging the ends of the column labels.



    10. Change the output viewable mode to Machine readable, if desired



    11. View the SPARQL Query as Graph model by clicking the Load Query to QBE button shown in the Toolbar with Result, SPARQL Params, Response, and Query sub-tabs.



    Execute another query

    Now we will enter a different SPARQL query to execute, to show how the navigation buttons (grayed-out blue arrows in the toolbar of the Results tab) work. You can find this SPARQL Query in the ODS SPARQL Queries list and also in the ODS Feed Manager SPARQL Queries list. It should obtain a dump of all Posts within an ODS-Feeds Data Space for user "demo".
    PREFIX   sioc: <http://rdfs.org/sioc/ns#>
    PREFIX  sioct: <http://rdfs.org/sioc/types#>
    PREFIX    dct: <http://purl.org/dc/elements/1.1/>
    PREFIX    dcc: <http://purl.org/dc/terms/>
    SELECT  ?forum_name
            ?channel
            ?item_title
            ?created
    FROM <http://demo.openlinksw.com/dataspace>
    WHERE
      {
        ?forum    a                  sioct:SubscriptionList                            ;
                  sioc:id            ?forum_name                                       .
        ?forum    sioc:scope_of      ?role                                             . 
        ?role     sioc:function_of   <http://demo.openlinksw.com/dataspace/demo#this>  .
        ?forum    sioc:parent_of     ?channel                                          .
        ?channel  sioc:container_of  ?post                                             .
        OPTIONAL { ?post  dct:title    ?item_title }  .
        OPTIONAL { ?post  dcc:created  ?created    }  .
      }
    LIMIT 20
    
    1. Click to the Advanced tab. Change the SPARQL Query to the above.



    2. Click the Run Query button on the Advanced toolbar.
    3. The Result sub-tab will present the results of the query.



    4. With the blue navigation buttons shown after the Query sub-tab, you can view the results of the first, previous, next and last executed queries. Click the furthest-left blue arrow.
    5. The results of the first query we executed -- all Weblog Posts for the ODS Member "demo" -- will be shown. Note that the content of the SPARQL Query area of the Advanced tab has also changed to match.



    References

    ODS SPARQL Queries

    ODS Applications SPARQL Queries

    ODS Application Name SIOC Reference SPARQL Query Using Atom OWL Ontology SPARQL Query Using SKOS Ontology SPARQL Query Using FOAF Ontology
    Weblog SIOCRefBlog ODS-Weblog Data Query ODS-Weblog Data Query ODS-Weblog Data Query
    Briefcase SIOCRefBriefcase ODS-Briefcase Data Query ODS-Briefcase Data Query ODS-Briefcase Data Query
    Feed Manager SIOCRefFeeds ODS-Feed-Manager Data Query ODS-Feed-Manager Data Query ODS-Feed-Manager Data Query
    Wiki SIOCRefWiki ODS-Wiki Data Query ODS-Wiki Data Query ODS-Wiki Data Query
    Calendar SIOCRefCalendar ODS-Calendar Data Query ODS-Calendar Data Query ODS-Calendar Data Query
    Bookmark Manager SIOCRefBookmark ODS-Bookmark-Manager Data Query ODS-Bookmark-Manager Data Query ODS-Bookmark-Manager Data Query
    Gallery SIOCRefGallery ODS-Gallery Data Query ODS-Gallery Data Query ODS-Gallery Data Query
    Addressbook ODSAddressBookRef ODS-Addressbook Data Query ODS-Addressbook Data Query ODS-Addressbook Data Query
    Discussions SIOCRefDiscussions ODSAtomOWLRefExampleDiscussions ODS-Discussions Data Query ODS-Discussions Data Query
    Community SIOCRefCommunity ODS-Community Data Query ODS-Community Data Query ODS-Community Data Query
    Polls SIOCRefPolls - ODS-Polls Data Query ODS-Polls Data Query

    Other Virtuoso SPARQL Queries