Currently I am using an RDF graph database (Ontotext GraphDB), which I query using a SPARQL query via dotnetRDF and C#.
Via the SparqlResultSet I can access the data and create a typed object/poco, but I am looking for some magic like Dapper, but then for RDF databases. Create a query, execute it and get typed data as a result.
Is there something like that, or functionality to build poco's from a result? I am not tied to dotnetRDF, an alternative is also an option.
RomanticWeb might do what you need. Unfortunately the project site appears to be down at the moment, but the packages are all available via NuGet.
You may also have a look at Iride. It is an F# library but can be used from C# via a thin F# project which does not require any knowledge of the F# language, just a series of type declarations like:
type Q = SparqlQueryProvider<"SELECT * WHERE { ?s ?IRI_p $INT }">
So you can write SPARQL queries and the type provider will create a method (Q.GetText) to pass input parameters and a POCO wrapper (Q.Result) for the result variables.