Creating custom output-files considering the original data

Hello there,

I just got introduced to KNIME a couple of days ago and I am really in love with the software. I am now just trying to build my very first and own workflow. But I am facing some problems and I was hoping to find some guidance in the forum. Maybe someone has a good idea how to solve this issue.

I do have a table. And I want the software to create several output files for me. I want to look up in a certain column how many different entries it has. And whenever the value changes I want to write a new output file.

Let’s say. I have a column thats named “job number” and the number of rows with the same job number can vary. But whenever the next line with a new job number starts I want a new outout file to be written gathering all the entrys that belong to the same job number. And I want to do this for all the different job numbers.

My problem is I never know how many different job numbers there are and the number of entrys vary. Otherwise I would have found a similiar forum entry. Unfortunately it does not work for me.

Does someone have an idea which node I could use for this? Or maybe someone has read something similiar in the forum already? That both could be very helpful. I’d be very happy about every hint I could get :- )

Many thanks in advance already.

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Hi @Sarah1989

That’s a job for the Group Loop node :slight_smile: Pro tip: have a look on the community hub. Whenever you look for a node there, you’ll find a section with example workflows that uses the node.

For example:


Hello ArjenEx :slight_smile:
Thank you so much for the quick reply. I did not know this node yet and had to install it first. That was very helpful. Thank you so much! It kind of does work. But I am still doing something wrong.
table splitter
It’s doing an iteration whenever I restart or hit the “execute” button on the variable loop end. But I dont want to press the button all the time. How do I tell this mini itsy bitsy workflow to loop on its own?
Do you know?

Hi if you run the (the complete) workflow it normally runs all iterations.

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@Sarah1989 scheduling would be a KNIME Business Hub function. One thing I once built was this - more to demonstrate how it could be done then to actually use this in production:

Thank you all so much for your help! I am very happy to see this community is such an active and cooperative one. I hope I will get there one day, too. By the way I found my error. My loop ended in a queque state, because in the Excel Writer Node I had the option checked to open the file after its done writing. So it opened the output file after the first iteration and therefor wasn’t able to start the next iteration. When de-activating this option the workflow runs through smoothly :slight_smile:


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