Hi all - My workflow generates new columns outputs after executing (named External Record ID, Record External Source) and they get written to the Excel file. The issue I’m facing is if I execute the new Excel file (with the new columns) again I want those to be overwritten with the new values in each of those columns, however, since Knime recognizes those columns as existing already, it duplicates them iteratively (#1, #2, etc. gets appended if there are duplicates). How would I select the new versions of the columns while still maintaining the option if this is the first time the workflow is being run where the columns don’t exist, but still have logic to handle when they already do.

Duplicate Column Selection

mlauber71 February 24, 2021, 7:26am 2

@mvaldes you could try one of these options. A suggestion by @Iris to use a Table Validator

Or there is this switch based on a Java snippet

And then you might just create an empty column of that name in the first place.

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