Cayley dump in Cayley v0.6.1 writes 0 quads to dump file



when I try to perform a db dump in Cayley v0.6.1 with this command:

cayley dump -db "bolt" -dbpath "./db.bolt" -dump_type "graphml" -dump "./dump.graphml"

I get:

dumping db to file "./dump.graphml"
0 entries were written

I have quads in my db, but I get “0 entries were writtten”. Is there something wrong with my command?