flow variables and source nodes

KNIME Analytics Platform
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Hello

I’m wondering if it is possible to use flow variables to set variables in source nodes. It appears that it is not, because it appears that variables are carried along with data into nodes. Is that correct? Specifically, I’m trying to dynamically set the database url parameter of a database reader node.

Thanks you,
Dave

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Hi Dave,
You are right, it’s not possible to inject variable into source node such as the Database Reader or File Reader. The only way I could think about is to define a workflow variable on the project itself, which then can be used in all nodes. Not sure if this makes sense in your case. Apart from that, if you manage to use the Database Looper is some way, you can replace the URL dynamically - but I never tried it…
Regards, Thomas

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Thanks Thomas. I might look into that. I was also thinking about deriving my own custom node, based on the code for the database source nodes to create a database reader node that had an input port.

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