Is it possible to import an rdf database into mysql or is there a way to convert it to sql?

RDF is XML; so yes. I don't know of any programs that do it for you but you should be able to trivially write one.

Yes it is possible

here are some tools

http://www.dmoz.org/Computers/Internet/Searching/Directories/Open_Directory_Project/Use_of_ODP_Data/Upload_Tools/