Problems with Database Nodes KNIME 4.0

Hello there KNIMErs,
I’ve tried to use the new “DB Connector” - Node.
I have problems with Connecting to MSSQL-Databases.
I want to give the Username and the Password to the Node as a flow variable but if I do this
and then i select “Username & password” in the Connection Settings it seems like it doesnt take
my flow variables.

Then I’m getting the error “ERROR DB Connector 4:51:0:28 Execute failed: Login failed. The login is from an untrusted domain and cannot be used with Windows authentication.”

But this User with the same password works on the Legacy DB Connector Nodes.

And I tried it with the Input Credentials, then it works!

I hope you can help me,


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I found out that password doesn’t get read from the flow variables, it gets taken from the “Connection Settings” page instead. How Can i use a password as a flow variable here?

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Hi stofffetzen,
the new DB Connector node no longer supports plain text passwords ans input. To set the password via flow variable you have to use the Credentials Configuration node where you set the default password via the flow variable. The credential can then be used in the DB Connector node. Have a look at the this example workflow.


Hi Tobias, thanks for the answer.
I tried this already and I had another problem :smiley:
We are using the DB Connector Node in our templates and
if I create a Component with a Credential Configuration it automatically
wants me to insert my Credentials when I open the Job.

We are sharing the Templates on our KNIME Server and if we want
to download them with this Credential Node inside them KNIME
starts crashing and you must shut it down.

I could try to save the password (weakly encrypted) in the Credential
Node but then I can’t use the password as a flow variable.

Do you understand my problem? :slight_smile:

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Hi @stofffetzen,

thanks for bringing this up. We were able to reproduce your problem, developers were informed and the issue will be resolved in a future release.

For the time being you can first copy the template from the server to a local workspace and then link (=drag&drop into workflow) from there. This options were tested to work in KNIME 4.0.

Best regards,

EDIT: removed the option that does not work :slight_smile:

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How did you test it with Credentials Input?
I share the template (Component with Credentials Input) on our KNIME Server
and if I Drag & Drop it from there it doesnt stop downloading and KNIME
gets stuck in the Step to Extract the downloaded workflow.

I configured the Credentials Input to don’t save the password weakly encrypted
because otherwise i cant use the password as a flow variable for the default
password value.

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you are right, I have put the Input node without specifying the user name and password. This way d&d the template from a remote server into a workflow works. There is no credentials pop-up upon d&d, but you can still change credentials in the component configuration dialog

As soon as I configure default username+password, I can not copy such template with Input anymore



Okay my templates are for reading database connection properties
out of a XML file and automatically connect with that properties to
the database.

I think for my purpose it will be better to wait for the next update of
KNIME and then implement the corrected version of the credential

Despite the fact that this doesnt work currently thanks a lot for
reading my support request :slight_smile:

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