Database reader

I just tried to connect through an ODBC driver to a database, and it worked - unfortunately just once. :-( Now I repeatedly get the following console message:

WARN Database Reader Configure failed: Could not decrypt password.

Any workaround known for this? My previous forum searches did not really yield any usable results, neither did tinkering with files in "workspace\.metadata".

Thanks,
Ergonomist

I had the problem once and it helped to simple reset the node and open and close the dialog again. Does this work for you as well?

Hi, also a restart of KNIME should help, because KNIME will then ask to re-enter the Master Key, please make sure you enter the same key as the last time. In KNIME 2.0 the Master Key dialog will change, that is, the Master Key can also be entered through KNIME's Preference Page and can optionally be stored. Let me know if it is working now. Cheers, Thomas.

Thanks for the hints! Unfortunately neither of them have helped so far...

I'm beginning to suspect that it's due to my restricted (i.e. non-admin) Windows account - or is that technically impossible? Even re-extracting KNIME from scratch from the original archive gave me that error, which lead me to suspect that. Or might a reboot help (something I rarely do and haven't done so far, either)?

Thanks,
Ergonomist

EDIT/P.S.: Is there an expected date for KNIME 2.0 already? :-)

UPDATE: As feared, rebooting didn't help either. As I drag the database reader onto the (empty) workspace, it already complains on the console. :-/

Any hint on where the password data is stored?

Thanks,
E.

I doubt that this has something to do with your database account, given that it was working before. Btw, are you using the same workspace after reinstalling KNIME? However, to reset the database history, you can try to delete the following files in your workspace directory "workspace/.metadata/": history_database_drivers.txt, history_database_library_files.txt, history_database_urls.txt, and history_drriver_urls.txt.

Thanks for the hint - been there, done that. I've even deleted the entire workspace folder, to no avail. That's why I wonder where KNIME stores the (encryption and/or database) passwords at all, since it doesn't have too many options on my locked-up machine.

Updating KNIME and downloading extensions doesn't work either, by the way, though that may easily be caused by the firewall which I assume we have.

EDIT for previously missed question: I used the default workspace again, yes. Will try with a new one now.

Kind regards,
E.

Passwords in KNIME are encrypted by the Master Key you have to enter the first time you configure/execute the database node. The encrypted password is saved inside the node's settings XML file located inside the workspace/project/node directory, whereby the Master Key is not and can't be stored before KNIME 2.0.

That explains a lot, thank you. Though I'm inclined to believe passwords are stored in and *encrypted* way in the XML file, as opposed to your indication... ;-) Not that it mattered much with our easy-to-guess DWH passwords. :-P

Anyhow, for whichever reason it now appears to work, even though it still complains on the console upon node creation. Strange, but I can live with that. Looking forward to KNIME 2.0, will it be there before autumn? :-)

Thanks for everything,
E.

On the creation of this node, there are no settings available unless you open the dialog and enter a valid URL, driver, etc. That's why the node complains the first time you drag it onto the workbench.

Got it. So I was simply too attentive of KNIME's complaints after I had noticed them for the first time. Any chance to fix that behaviour in a future release to provide a better user experience? It's sometimes just those little things that make the difference, after all (classic ergonomics and usability reasoning). :-)

Kind regards,
Ergonomist

By the way, this keeps happening, it's apparently not only a matter of excessive error message generation... :-/

-E

With KNIME 2.0 we still issue a warning when a node tries to auto-configure itself, but of course the warning message is much nicer saying that no dialog settings are provided to establish the database connection. Cheers, Thomas.

I'm happy to hear that. I fixed my DB reader problems so far, but whenever I notice new oddities I'll post again.

E.