set metadata field

Hi,

I'm new here. I need to import my csv data to calibre. As mentioned in the manual there's a command where i can update some fields. The manual says under the topic calibredb set_metadata that one can use te option --field instead of using opf files: "You can also set the metadata of individual fields with the –field option."

Has anyone an example of this. I got an error when I try to change a field:
"... file not found":

calibredb set_metadata 7 --field timestamp "01.01.2000"
Traceback (most recent call last):
File "site.py", line 58, in main
File "site-packages/calibre/library/cli.py", line 1301, in main
File "site-packages/calibre/library/cli.py", line 577, in command_set_metadata
File "site-packages/calibre/library/cli.py", line 500, in do_set_metadata
File "site-packages/calibre/ebooks/metadata/opf2.py", line 553, in __init__
IOError: [Errno 2] Datei oder Verzeichnis nicht gefunden: u'01.01.2000'

Thanks in advance !
Fr3d