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Ruben.Taelman@UGent.be
@rubensworks
Query the Web of Linked Data with GraphQL queries
Highly popular JSON-like query language for graph-based data
We convert GraphQL queries to SPARQL using a JSON-LD context
LD-
Can only be used to query a single GraphQL interface
no link with Semantic Web technologies
Try it at http://query.linkeddatafragments.org/
GraphQL Query
JSON-LD Context
{
label
}
{
“label”: “http://www.w3.org/1999/02/22-rdf-syntax-ns#”
}
+
= SELECT ?label
WHERE {
_:b <http://www.w3.org/1999/02/22-rdf-syntax-ns#label> ?label
}
SPARQL Query
GraphQL developers can now query with any SPARQL engine.
=> no universal semantics over different interfaces
GraphQL-LD queries have universal semantics,
which enables federated querying over multiple sources.

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Poster GraphQL-LD: Linked Data Querying with GraphQL

  • 1. Ruben.Taelman@UGent.be @rubensworks Query the Web of Linked Data with GraphQL queries Highly popular JSON-like query language for graph-based data We convert GraphQL queries to SPARQL using a JSON-LD context LD- Can only be used to query a single GraphQL interface no link with Semantic Web technologies Try it at http://query.linkeddatafragments.org/ GraphQL Query JSON-LD Context { label } { “label”: “http://www.w3.org/1999/02/22-rdf-syntax-ns#” } + = SELECT ?label WHERE { _:b <http://www.w3.org/1999/02/22-rdf-syntax-ns#label> ?label } SPARQL Query GraphQL developers can now query with any SPARQL engine. => no universal semantics over different interfaces GraphQL-LD queries have universal semantics, which enables federated querying over multiple sources.