~$ mtn help db
...
Options specific to 'mtn db':
  --drop-attr=STRING     when rosterifying, drop attrs entries with the given
                         key

     db init
     db info
     db version
     db dump
     db load
     db migrate
     db execute
     db kill_rev_locally ID
     db kill_branch_certs_locally BRANCH
     db kill_tag_locally TAG
     db check
     db changesetify
     db rosterify
     db set_epoch BRANCH EPOCH
       manipulate database state