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 ?role , ?forum_name, ?post, ?title, ?cr, ?url  
WHERE    
  { 
    ?forum a sioct:Weblog .
    OPTIONAL{ ?forum sioc:id ?forum_name }.
    OPTIONAL{ ?role sioc:function_of <http://id.myopenlink.net/dataspace/demo#this> }.
    OPTIONAL{ ?forum sioc:scope_of ?role } . 
    OPTIONAL{ ?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 http://cname/isparql, for ex. http://id.myopenlink.net/isparql
  2. The iSPARQL initialization window will be shown:



  3. On successful initialization will be presented the iSPARQL Advanced tab open with a default SPARQL query: 

    SELECT * WHERE {?s ?p ?o}





  4. Go to QBE tab:



  5. Click the Clear Pane icon on the toolbar to empty the Canvas.







  6. 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., http://id.myopenlink.net/dataspace



  7. Click the Advanced tab.
  8. Change the Graph value to also be as in our example http://id.myopenlink.net/dataspace and enter (copy-and-paste) the query chosen above into the SPARQL Query text-area:



  9. Click the Run Query button on the Advanced tab.
  10. The Results sub-tab shown below the Results tab will present the results of executing our SPARQL Query:



  11. Additionally you can change the results table column widths by dragging the ends of the column labels:



  12. View the SPARQL Query as Graph model by clicking the Load Query into QBE button shown in the Toolbar.



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://id.myopenlink.net/dataspace>
WHERE
  {
    ?forum a sioct:SubscriptionList;
                   sioc:id ?forum_name.
    OPTIONAL{ ?forum sioc:scope_of ?role }.
    OPTIONAL{ ?role sioc:function_of <http://id.myopenlink.net/dataspace/demo#this> }.
    OPTIONAL{ ?forum sioc:parent_of ?channel }.
    OPTIONAL{ ?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 tab will present the results of the query.



  4. With the blue navigation buttons 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 NameSIOC ReferenceSPARQL Query Using Atom OWL OntologySPARQL Query Using SKOS OntologySPARQL Query Using FOAF Ontology
WeblogSIOCRefBlogODS-Weblog Data QueryODS-Weblog Data QueryODS-Weblog Data Query
BriefcaseSIOCRefBriefcaseODS-Briefcase Data QueryODS-Briefcase Data QueryODS-Briefcase Data Query
Feed ManagerSIOCRefFeedsODS-Feed-Manager Data QueryODS-Feed-Manager Data QueryODS-Feed-Manager Data Query
WikiSIOCRefWikiODS-Wiki Data QueryODS-Wiki Data QueryODS-Wiki Data Query
CalendarSIOCRefCalendarODS-Calendar Data QueryODS-Calendar Data QueryODS-Calendar Data Query
Bookmark ManagerSIOCRefBookmarkODS-Bookmark-Manager Data QueryODS-Bookmark-Manager Data QueryODS-Bookmark-Manager Data Query
GallerySIOCRefGalleryODS-Gallery Data QueryODS-Gallery Data QueryODS-Gallery Data Query
PollsSIOCRefPolls-ODS-Polls Data QueryODS-Polls Data Query
AddressbookODSAddressBookRefODS-Addressbook Data QueryODS-Addressbook Data QueryODS-Addressbook Data Query
DiscussionsSIOCRefDiscussionsODSAtomOWLRefExampleDiscussionsODS-Discussions Data QueryODS-Discussions Data Query
CommunitySIOCRefCommunityODS-Community Data QueryODS-Community Data QueryODS-Community Data Query

Other Virtuoso SPARQL Queries

Related

CategorySPARQL CategoryRDF CategoryOpenSource CategoryOAT CategoryDocumentation CategoryTutorial