String Replace: Add option to return missing upon no match


the String Replace has a UX flaw as it is returning the entire cell value when the pattern does not match. I’d like to suggest to enable to return missing in these cases to prevent data corruption, improve workflow reliability and grand more precise control of the data.

Test workflow


Hey @mwiegand ,

the Regex Split – KNIME Community Hub should do what you desire.
In the nightly, that node is already updated and renamed to “String Splitter (Regex)” with additional functionality planned to be released with 5.3. Happy to hear your feedback.

Have a nice day,


Thanks for your feedback. The RegEx split node might be another option but what I pointed out is still valid and more a bug, isn’t it?

If you are in a text editor and use the find&replace feature: Would you expect all text to disappear, if the pattern does not match? Personally, I see each cell in the table as one little “text editor” on which the node does Find&replace. Hence, in my opinion extracting substrings is a different task, which is covered by that other node. Though, open for feedback.

Using your analogy of a text editor. If I search & replace, using RegEx with a capturing group, a sub-string but none was found, I expect none given back and certainly not the entire string. This is especially true if a new column is appended with the result of the capturing group.

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