 rdf_db_to_file(?DB, 
?FileBase)Convert between DB (see rdf_source/1) 
and file base-file used for storing information on this database. The 
full file is located in the directory described by rdf_current_db/1 
and has the extension
rdf_db_to_file(?DB, 
?FileBase)Convert between DB (see rdf_source/1) 
and file base-file used for storing information on this database. The 
full file is located in the directory described by rdf_current_db/1 
and has the extension
.trp for the base state and .jrn for the 
journal.