Connect multiple variables to one node

I’m creating a custom component and, using the Column Selection Configuration nodes, I want to let the user choose two columns to use in the Unpivoting node. So far I have not found a way to connect both configuration nodes to the Unpivoting node and choose the selected columns as value columns in the Unpivoting configuration.

Hi @marcandavi and welcome to the Knime Community.

Can you show us what you have done so far, or even may be share your workflow so we can take a look?

  1. There’s a Merge Variables node that you could explore
  2. Keep in mind that variables propagate through downstream nodes. You don’t necessarily have to connect a variable node directly to the node in which it’s going to be used.

Hi, thank you all for your comments, I provided you with a sample of my problem

test component.knwf (25.6 KB)

1 Like

In this case you need to supply the pivoting node with a variable that contains an array of column names. The icon next to the flow variable image
gives you that hint.

One way to handle this is to create a collection column with the variables:

In the Joiner node, I do an inner join on RowID

Here’s how I create the collection column:

And here’s the setup of the Unpivoting node:


Hello @marcandavi and @elsamuel,

one can use Column Filter Configuration or Column Filter Widget node in this case as it outputs array flow variable holding included column names.

Welcome to KNIME Community @marcandavi!



Thank you both @elsamuel and @ipazin!
I ended up using a solution that is a mixture of your suggestions and works fine!

1 Like

This topic was automatically closed 182 days after the last reply. New replies are no longer allowed.