workflow Groupby, ...Pivoting

Hello All, I need to select the biggest values in a given column. To do that, I used Groupby, sorter, Row filter, RowID and then pivot.
Strange thing is that pivot output shows “?” (I double checked, there is no “?” in table as shown in ‘Processed data’)

Do you have any idea of the reason ? What corrections do I have to do ?

Thank you for your help,



Hi @olivier92410 , a red “?” simply means that the value is empty, the value is null. It’s how Knime represents an empty value.

This can happen when pivoting if some data do not have the same amount of rows/columns (rows or columns depending what your pivoting is doing)

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Many thanks for your reply !
I understand the cause is the “age bin”. Then, I can have multiple rows par bin…
I there any other way ? (in my case, I’m trying to sort the ten highest salary grouped by gender, and bin age)

Thank you for your help !

Hi @olivier92410 , I don’t quite understand the use of the Pivoting node here.

For what you described, this can be done in just 1 node, the GroupBy node.

In order to help you, you will need to provide some sample data and also show what the expected results should be (just so we can confirm that we understood what you are trying to do)

EDIT: Well, in 3 nodes rather - after the GroupBy, you’d want to sort and then do a row filter

Yes, here is some information on what I’m trying to do,
In the end, I need to figure out delta between men and women count, per age bin, for the ten highest salaries,

Hope it is clearer,

Thank you for your help !



Biggest value in a column sounds like math formula COL_MAX. Have you already taken a look at that
br

Hello Daniel,

highest values come from ‘Sorter’ node that comes after a ‘Groupby’ node (see image once grouped),

So, what is your point then ?