iSPARQL Querying Tutorial with SPARQL Query type "DESCRIBE".

This tutorial shows how to execute a SPARQL query with type "DESCRIBE".

Enter and execute a query

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. In the Schemas pane, import the schema with URL http://rdfs.org/sioc/types#>:
   
   
   
   
7. In the Schemas window under "unbound", you should now see sioct. Click the + icon for "Classes" in order to expand it.
   
   
   
   
8. Scroll down the shown list and drag-and-drop the Subject Node Weblog onto the QBE working Canvas.
   
   
   
   
9. Select the empty node and, in the Variable field of the "Node" pane, enter the value: ?forum:
   
   
   
   
10. 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://id.myopenlink.net/dataspace
    
    
    
    
11. On the QBE tab, apply the following changes:
    1. Select DESCRIBE for Type.
    2. Select 10 for Results Size Limit.
       
       
       
       
12. Click the Run Query button on the QBE toolbar.
13. The Results sub-tab shown below the Results tab will present the results of executing our SPARQL Query with type "DESCRIBE":
    
    
    
    
14. To view the produced SPARQL query, click the Load Query to Advanced button.Note: you can also view the produced SPARQL Query in the QBE tab by clicking the Generate button on the QBE toolbar.
15. The Advanced tab will open, with the produced SPARQL query with type "DESCRIBE" in the SPARQL Query text-area:
    
    
    
    

Related

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• Basic iSPARQL Tutorial with query built from a blank canvas and Nodes dragged from the Toolbar
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• OpenLink AJAX Toolkit (OAT)
• Virtuoso Documentation SPARQL Query examples