I am using Refine with RDF Extension to produce triples from a CSV. I have imported two vocabularies and am now using them to describe the columns:
How can I change the nodes to describe resources rather than literals? For example, when I preview the Turtle representation, the triples map to literals, such as geolink:hasDocumentType "datasets":
Can I create empty nodes in Refine to hold the place of resources, such as Document Type? Thanks!
This is assigned in the dialog for the mapping. See "The cell's content is used ..." and then choose "as a URI".
(sorry for the broken dialog rendering)
Then you choose "Use custom expression" where you can make up your own URI scheme. In this example I simply add the value of the cell to a fix URI pattern:
In the preview you can directly see if this is what you need.
If I need to do more complex things I usually create simple key-value like RDF, so technically not really a graph yet. Then I write a bunch of SPARQL CONSTRUCT queries to clean up the data and transform it into a "real" graph. I found that for many things easier and faster. You can see some examples on Github