Remove columns dynamically

[aakashraj]

Hi Everyone,

I am new to Knime. I am trying to filter out some column dynamically. I am using Column filter configuration to select some columns. Then using flow variable, I am trying to remove these columns from the main data flow by using column filter node. However, the I am not getting desired output.
Request you to please help.

Thanks

[ipazin]

Hello @aakashraj,

and welcome to KNIME Community!

but Column Filter Configuration node already does filtering so I don’t see a need for Column Filter or I’m missing something?

Br,
Ivan

[aakashraj]

Hi Ivan,

Thanks.
My requirement has few more steps. I want to dynamically select few columns using Column Filter Configuration and want to do some operations on those columns. After this I want to append the modified data with rest columns. Since this operation will lead to duplication of the selected columns, I want to remove those specific columns to avoid duplication of data.
Hope this helps to clear the requirement.

Thanks

[ipazin]

Hello @aakashraj,

I see. Here are couple of points/remarks/ideas:

• to control Column Filter exclusion list with flow variable move all columns to exclude list and check Enforce exclusion option
• you can connect Column Filter Configuration directly to Column Filter node using flow variable connection and avoid Extract Column Headers and Table Row to variable nodes
• usually before Column List Loop Start node Column Splitter node is used to avoid duplication
• is it possible you can replace all nodes after String Manipulation (Node 24) with single String Manipulation (Multi Column) node? It features CURRENTCOLUMN placeholder in Column List to apply same expression to all chosen columns?

Br,
Ivan