change a Value

hi, i am trying to change a value (String) in a column and i used String Manipulation Node for that but it did not work. i do not want remove the Row. i want only change the string to another one. could someone say to me, which node should i use?

Hi there!

There are couple of possibilities. First that popped on my mind are Cell Replacer and Rule Engine nodes. Try both and see what you like more :wink:


// enter ordered set of rules, e.g.:
// $double column name$ > 5.0 => “large”
// $string column name$ LIKE “blue” => “small and blue”
// TRUE => “default outcome”
$Technology$ LIKE “_tbd” => “Null”

thank u. i tried to do it like this the Column Name ist Technology and i want change “_tbd” to another value . i think i made a mistake but i do not know what should i do ? could du help me ?

thank u


Hi Hussein!

It seems to me that your rule is fine. Only you should add another rule in case Technology is not “_tbd” or you will get missing values (?) for those values. In order to do that you should use “TRUE => …”. I have attached example workflow so take a look if it is not clear.

RuleEngineExample.knwf (7.0 KB)


hi Ivan,

thank u so much. i tried it with your Example also but it doesn’t work also. :frowning:

could it be the problem? That i use Excel Reader?

Hi Hussein,

not sure what is the problem. What is the error you get? It would be best if you can attach a workflow.


Oh sorry it works but it give me a new column name Prediction. Can i change that to replace tge column Technologie?

KNIME_project.knwf (10.3 KB)

No problem. Glad it works :slight_smile:
Regarding name column, in Rule Engine node configuration you chose if you wish to replace column or add a new one. If you are adding a new one by default column name is prediction which you can change of course. Here is node settings where you can see it:


Thank you very much Ivan

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