[GitHub] zeppelin issue #3087: [ZEPPELIN-3644]: Adding SPARQL query language support ...

[NicolasRouquette]

Github user NicolasRouquette commented on the issue:

    https://github.com/apache/zeppelin/pull/3087
  
    FYI: It is possible to use the R SPARQL package:
    
    https://cran.r-project.org/web/packages/SPARQL/index.html
    
    For example, here's the web interface to ACM's SPARQL endpoint:
    http://acm.rkbexplorer.com/sparql/
    
    With Zeppelin, we can do the same thing with two paragraphs:
    
    ```
    %spark.r
    library(SPARQL)
    
    endpoint <- "http://acm.rkbexplorer.com/sparql/";
     
    query <-
    '
    PREFIX id:   <http://acm.rkbexplorer.com/id/>
    PREFIX rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
    PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
    PREFIX akt:  <http://www.aktors.org/ontology/portal#>
    PREFIX owl:  <http://www.w3.org/2002/07/owl#>
    PREFIX akt:  <http://www.aktors.org/ontology/portal#>
    PREFIX akts: <http://www.aktors.org/ontology/support#>
    
    SELECT * WHERE { ?s rdfs:label ?o }
    LIMIT 10
    '
    
    qd <- SPARQL(endpoint,query)
    r <- qd$results
    df <- as.DataFrame(r)
    registerTempTable(df, "ACM")
    ```
    
    and:
    
    ```
    %sql
    select * from ACM
    ```
    
    Obviously, this solution lacks SPARQL-language specific syntax highlighting 
or completion;
    however, it is very convenient for executing SPARQL queries.


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