Merging multiple rows

Hi! I’m struggling to find a way to merge multiple rows into one.

Let’s say I’ve three different product rows with sold units and I want merge these into one row so that the outcome has calculated sold units together.

I also want to change product names to the category name.

Can anyone help me?

Hi @vesamatti,

you can use the group by and concatenate the columns row wise.

There are many more opportunities to like creating a collection column and converting the collection to a string. In combination with transpose you have almost infinite possibilities.


1 Like

Thanks @mw. I’m newbie with Knime coming from Tableau. I’m trying to find a similar solution than Tableau Preparation has for merging/combining rows.

Would you like to give me an example about what could be the most similar tool?

Hi @vesamatti, it may be best for you to provide us with sample data to work with, along with a screenshot/description/example of what your desired output would be.

Otherwise, all the responses to this post will be variations on “it depends”.

1 Like

hello @vesamatti,

welcome to the knime community.
do you mean, you have one product in three rows? then you could use the group by node.
do you mean, three products in three rows and you want to calculate the total of the three rows?


1 Like

Hi @sven-abx,

Please see the attachment. I’ve demonstrated the starting point and expected outcome.

Screenshot 2020-06-25 15.45.26

Hi @vesamatti,

you either just want to get the sum via a GroupBy node, assuming the product name with it’s number sequence is irrelevant.

Or use the Math Formula node.


1 Like

Hi there @vesamatti,

have you managed to pull it off? You can browse KNIME Hub for workflow examples or upload some dummy data and someone can create a workflow example if needed. From experience that is always a good approach :wink:

Anyways welcome to KNIME Community!


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