Hi. I am trying to get a basic example. I am trying to run your example with dbpedia with Country and City. When I query a city using the GraphiQL, I get the city Id but if I try to get the city and country, I get the following error:
Exception while fetching data (/City_GET[0]/country/_id) : class java.util.ArrayList cannot be cast to class org.apache.jena.rdf.model.RDFNode (java.util.ArrayList is in module java.base of loader 'bootstrap'; org.apache.jena.rdf.model.RDFNode is in unnamed module of loader 'app')

I am using the pre-built jar located at: https://www.hypergraphql.org/resources/hypergraphql-3.0.1-exe.jar
My query is:
{ City_GET(limit: 5) { _id _type country { _id _type } } }
Config: https://github.com/hypergraphql/hypergraphql/blob/master/src/test/resources/test_configurations/config1.json
Schema: https://github.com/hypergraphql/hypergraphql/blob/master/src/test/resources/test_configurations/schema1.graphql

Let me know what I am missing.