pre-note: I would recommend using FeatureReaders and FeatureWriters instead of Readers and Writers because things will be a bit more intuitive.
You say you want to add data to an excisting Excel-file, but you are reading a CSV file and then using an InlineQuerier to add some other source. This looked a bit confusing to me at first, but I think the InlineQuerier is reading the Excel?
I think I would do the following:
Creator → FeatureReader (Excel) + FeautureReader (CSV) → FeatureMerger → AttributeValueMapper → FeatureWriter (Excel)
I usualy don't like to ‘update’ the same Excel, but write a new Excel with the same data, but it can be done using the xlsx_row_id to write the data to the same row as it came from.
thanks for the recommendations @jkr_wrk.
I used some of the ideas you gave me to work out what I was trying to achieve.
cheers.
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