I am unsure how to output the results of a group by where there is a manually aggregated LIST.
It appears as data type ‘(…)’, and shows up well in KNIME, but I cannot seem to export this successfully to Excel. All the other columns/data types seem to come through fine into Excel.
Any suggestions please?
The reason you cannot map it is because Excel does not support that data type. I recommend using the Split Collection Column node to separate the value into multiple columns and then use the Column Aggregator to concatenate into a string. Then you will be able to see the field in the Excel Write (xls) node and map it.
Or alternatively, use the split collection column node, then an unpivot node to give you a normalised (i.e.: “narrow”) list, with repeating “topic id”. You could then write this out to Excel and use a pivot table to further analyse it or do that in Knime.
Instead of split and unpivot you can also use the ungroup node
Or use the concatenate aggregation in the GroupBy node for the column in the first place
Thanks for everyone’s input!