PostgreSQL Connector Error: "Database host is not defined" despite variable input

KNIME Analytics Platform
1

Hi KNIME community,

I’m encountering an issue with the PostgreSQL Connector node in KNIME. I’ve tried passing the database host as a Flow Variable, but when clicking “OK” in the node configuration, I get the error:

“Database host is not defined”

Steps I’ve taken:

  1. Defined a Flow Variable in the parent workflow’s variables.
  2. In the PostgreSQL Connector node configuration, selected the variable under Flow Variables for the “Host” field.
  3. Confirmed the variable name matches exactly (case-sensitive) and is properly scoped.

Expected behavior:
The node should accept the host value from the Flow Variable.

Actual behavior:
The error persists even after mapping the variable. If I hardcode the host directly in the node, it works fine.

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2

Hello @qwe52b ,
you need to add a dummy host name into the Host name field of the dialog in addition to setting the flow variable. During validation the host name field value is used and not the value of the specified flow variable. During execution the dummy host name is replaced by the value of the specified flow variable.
Bye
Tobias

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