database-for-rdf

Database for RDF

About the tool

The Resource Description Framework (RDF) is a format for structured data that uses triples to represent information. A set of RDF triples, a.k.a. an RDF dataset, can be stored in a database or file and queried using the SPARQL query language (similar to how SQL works for relational databases).

One of the key features of SPARQL is the SPARQL Federation. This allows querying multiple RDF datasets at once using the SERVICE keyword.

I've created this tool to experiment with storing, visualizing, querying, and federating over RDF datasets. You can use it to experiment, learn, and test your own queries.

To use the tool, enter your RDF data in the Turtle format and the SPARQL query. The tool supports the SPARQL Federation, which means you can, e.g., query your own RDF data and Wikidata at the same time. Have fun!

Demo

RDF data (Turtle)

@base <http://example.org/> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix wd: <http://www.wikidata.org/entity/> .


# Alice, Bob, and Carol are people

<alice> a foaf:Person .
<alice> foaf:name "Alice" .

<bob> a foaf:Person .
<bob> foaf:name "Bob" .

<carol> a foaf:Person .
<carol> foaf:name "Carol" .


# Alice knows Bob and Carol

<alice> foaf:knows <bob> .
<bob> foaf:knows <alice> .

<alice> foaf:knows <carol> .
<carol> foaf:knows <alice> .


# Alice watched two movies

<alice> <watched> wd:Q44578 . # Titanic
<alice> <watched> wd:Q488655 . # Groundhog Day


# Bob watched three movies

<bob> <watched> wd:Q162255 . # The Terminator
<bob> <watched> wd:Q83495 . # The Matrix
<bob> <watched> wd:Q91540 . # Back to the Future


# Carol watched one movie

<carol> <watched> wd:Q36479 . # The Lion King1
@base <http://example.org/> .
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@prefix foaf: <http://xmlns.com/foaf/0.1/> .
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@prefix wd: <http://www.wikidata.org/entity/> .
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# Alice, Bob, and Carol are people
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<alice> a foaf:Person .
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<alice> foaf:name "Alice" .
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<bob> a foaf:Person .
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<bob> foaf:name "Bob" .
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<carol> a foaf:Person .
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<carol> foaf:name "Carol" .
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# Alice knows Bob and Carol
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<alice> foaf:knows <bob> .
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<bob> foaf:knows <alice> .
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<alice> foaf:knows <carol> .
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<carol> foaf:knows <alice> .
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# Alice watched two movies
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<alice> <watched> wd:Q44578 . # Titanic
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<alice> <watched> wd:Q488655 . # Groundhog Day
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# Bob watched three movies
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<bob> <watched> wd:Q162255 . # The Terminator
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<bob> <watched> wd:Q83495 . # The Matrix
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<bob> <watched> wd:Q91540 . # Back to the Future
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# Carol watched one movie
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<carol> <watched> wd:Q36479 . # The Lion King

The RDF dataset in the Turtle format.

SPARQL query

# Does Alice know anyone who has watched an Arnold Schwarzenegger movie?

BASE <http://example.org/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX wdt: <http://www.wikidata.org/prop/direct/>

SELECT ?person ?movie
WHERE {
  <alice> foaf:knows ?person .
  ?person <watched> ?movie .
  SERVICE <https://query.wikidata.org/sparql> {
    # movie - cast member - Arnold Schwarzenegger
    ?movie wdt:P161 wd:Q2685 .
  }
}1
# Does Alice know anyone who has watched an Arnold Schwarzenegger movie?
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BASE <http://example.org/>
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PREFIX foaf: <http://xmlns.com/foaf/0.1/>
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PREFIX wd: <http://www.wikidata.org/entity/>
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PREFIX wdt: <http://www.wikidata.org/prop/direct/>
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SELECT ?person ?movie
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WHERE {
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  <alice> foaf:knows ?person .
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  ?person <watched> ?movie .
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  SERVICE <https://query.wikidata.org/sparql> {
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    # movie - cast member - Arnold Schwarzenegger
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    ?movie wdt:P161 wd:Q2685 .
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  }
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}

The SPARQL query to be executed against the RDF dataset.

Query result

Press Run query to execute the query against your dataset.

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