If you are just starting with KNIME do not feel bad about not coming up yourself with the solution above. It uses a couple of advanced concepts, namely loops and workflow variables, which probably you haven't looked into yet.
I think working with KNIME is a bit like playing with Lego. First you have to imagine what you want to build (end-state), then you have to find the right bricks (nodes) to build it, finally you have to assamble them together (workflow) to achieve the final result. It usually takes a bit of trial and error. Also there is not one single way to get to a given result and I can tell your for sure that also the most experience users learn something new every day.
There are few steps I can recommend you to learn KNIME (not necessarily in this order):
- Go through all the material on knime.org's Getting Started page, that's a good starting point.
Shameless promotion: I have also written myself 4 introductory tutorials to KNIME which you can find on my blog here http://marcoghislanzoni.com/blog
- Browse through the KNIME node description here: https://www.knime.org/files/node-documentation/index.html
These are the same descriptions you find within KNIME when you select/click over a node. The challenge is to find which nodes to focus on since there are quite a number of them (and that's an understatement). Starft with IO, Manipulation, Analytics, Views, Reporting; then look at Workflow Control, KNIME Labs, Community Nodes.
- Study the Example Workflows which you can access direclty from KNIME by connecting to the EXAMPLES server. They are very well documented and you can play with them by altering the input data, the configuration of the nodes, adding/removing nodes, etc.
- Read some of the White Papers published by KNIME. They are very well written and contain an in-depth explanation of how the problem was analysed and solved with KNIME. You can find them here: https://www.knime.org/white-papers
Some of the White Papers are slightly outdated but still valid.
- You can watch some videos from the KNIME TV on YouTube and/or purchase one of the KNIME publications from KNIME Press.
But first and foremost, I recommend you to play a lot with KNIME. Find some interesting data analysis problems, get some sample data sets (the classical Iris or others) and use KNIME to solve them. At the beginning you will struggle to "visualize" a solution and find the right nodes, but eventually you will crack the code and become proficient. If you have a programming or data analysis background you will go quicker, but it is not strictly necessary if you ask me.
If you get stuck, you can always ask on this forum. There is plenty of experts willing to help you. Just make sure you explain properly what you are trying to achieve and what your issue is. If possible attach your partial workflow and your test data to the post so someone else can quickly import it directly in their KNIME and show you how to fix it.
Sorry, this was a lengthy answer to a simple question. Enjoy learning KNIME! :-)