Data Mapping & Mapped Meta Data

Dear together,

I have several ontologies which i can import into stardog KG DB.
I have several relational databases which i would like to map to that imported ontologies.
My interest is mainly on the mapped meta data. I have given a try to mapping with csv data to a small ontology but is it possible to do it on scale i.e. using a SQL endpoint to some databases as mapping source. Second question as my interest lays on mapped meta data, how can i query which ontology class / attribute / relation mapped to which table/attribute etc. from SQL side.

Thanks a lot.