Possible bug in Row Filter node using flow variables


I observed a strange behavior of the Row Filter node that could be a BUG so I would like your opinion on it.

As you can see in the attached workflow, if I filter the rows with the option “include rows by number” manually setting the “Last row number” to 10, I obtain a table with exactly 10 rows. Nevertheless if I introduce this value using a flow variable (containing a value of 10), I obtain a table with 11 rows.

Is this a bug or I'm misunderstanding something? By the way I'm using the current knime version 2.12.1.

Thanks for your feedback,


Internally rows start from 0 whereas the dialog starts counting from 1. Therefore you get 11 rows when you set the value to 10 via a flow variable. Confusing, but this is the way it is.

Hi Thor,

Thank you for your quick answer. Yes, I was imaging what you explained but it is very confusing. In my opinion it doesn't make sense that the same value (i.e. 10 in this case) produces different outputs depending on if it is introduced manually or by a flow variable. I whould change one of the 2 to align the cases.



I agree on this one. While I understand the choices made separately for the dialog and the flow variables, they should be consistent.


Encountered the same thing today. A bit confusing :slight_smile: