CODEWITHSUNDEEP
sparqlrdfsemantic-webowlfuseki
Ania David
Ania David

Reputation: 1198

is there a way where I can write my RDF data DIRECTLY and query it via SPARQL

I'm practicing some SPARQL queries and features, my problem is that whenever I get new RDF data, I go to protoge, build classes and relationships and instances that accompany to these RDF, then explore these data, then import it to a dataset in Fuseki, then I query it. and if I make any mistake in my data, I'd need to repeat the whole process.

It's becoming tedious and time consuming, that's why I badly need to ask you if there's a place (tool or a fuseki support plugin ... or anything ..) where I can write my simple rdf data directly and then query it from my fuseki.

that data I want to write for example is really simple, it's like this:

@prefix dei: <http://www.warsaw.pl/ > .
    
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . 
    
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
    
dei:~rcardish/
    
      rdf:type foaf:Person ;
    
      foaf:name “Rafa Cardish" ;
    
 foaf:member <http://www.warsaw.pl> ;
    
      rdfs:SeeAlso <http://www.linkedin.com/in/rafacardish>

but even that simple and small rdf takes me time in my current way.

Your help is appreciated.

Update 1

Now I can do this to load my data into fuseki

./fuseki-server --file=/Users/bla bla bla/rdfData.rdf /testdataset

and this is the data

@prefix dc:   <http://purl.org/dc/elements/1.1/> .
@prefix :     <http://example.org/book/> .
@prefix ns:   <http://example.org/ns#> .

:book1  dc:title     "SPARQL Tutorial" .
:book1  ns:price     42 .
:book1  ns:discount  0.2 .

:book2  dc:title     "The Semantic Web" .
:book2  ns:price     23 .
:book2  ns:discount  0.25 .

but I don't know how to query it because when i run Fuseki, i go to query and I have to select a dataset but here there is no dataset shown in the drop down

Update 2

Now it's working, my mistake is that the file extension was .ttl.rdf, when I make it .ttl alone it works

Upvotes: 1

Views: 854

Answers (2)

CaptSolo
CaptSolo

Reputation: 1801

You can use command line tools (e.g. Redland tools) or write a simple script to load RDF and run SPARQL queries over it (e.g. using RDFlib):

1) Using Redland: roqet query.rq -D data.ttl -r json

Runnit it with a query for ?s dc:title ?title using your example data returns:

"bindings" : [
  {
    "s" : { "type": "uri", "value": "http://example.org/book/book1" },
    "title" : { "type": "literal", "value": "SPARQL Tutorial" }
  },
  {
    "s" : { "type": "uri", "value": "http://example.org/book/book2" },
    "title" : { "type": "literal", "value": "The Semantic Web" }
  }
]

JSON is one of result formats but you can also get CSV, etc.

See also: Command line Semantic Web with Redland

2) Using RDFlib to run SPARQL queries is also quite a compact way to do this (in Python):

import rdflib

g = rdflib.Graph()

g.parse("data.ttl", format="n3")

qres = g.query(
    """SELECT DISTINCT *
       WHERE {
          ?s dc:title ?title .
       }""")

for row in qres:
    print("%s : %s" % row)

Results:

http://example.org/book/book1 : SPARQL Tutorial
http://example.org/book/book2 : The Semantic Web

Upvotes: 1

Joshua Taylor
Joshua Taylor

Reputation: 85913

You can use Jena's command line tools to run SPARQL queries easily. In the Jena distribution, there's a sparql executable with --query and --data flags. Once you have your RDF file (if you're writing by hand, I'd suggest using the Turtle/N3 serialization and giving your file the .ttl or .n3 suffix), and then it's easy to run a query. For instance, when I have a data.n3 file like this:

@prefix : <http://stackoverflow.com/a/35854800/1281433/>

<http://stackoverflow.com/users/1281433/> :hasUserName "Joshua Taylor" .

and a query.rq like this:

prefix : <http://stackoverflow.com/a/35854800/1281433/>

select ?user where {
  ?user :hasUserName "Joshua Taylor"
}

Then I can get output like this:

$ sparql --query query.rq --data data.n3

---------------------------------------------
| user                                      |
=============================================
| <http://stackoverflow.com/users/1281433/> |
---------------------------------------------

Upvotes: 0

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