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Adding custom column to nested table
Is there a way to add a custom column to a nested table that references another column in the nested table? For example, I would like to add a custom "previousRow" column to the nested table in the p...
NewStep=Table.TransformColumns( #"Grouped Rows",{"Count",each Table.FromColumns(Table.ToColumns(_)&{List.RemoveLastN({null}&[externalLoad],1)},Table.ColumnNames(_)&{"PreRows"})})
I would add the indexes before the group step, and set up you previous row columns based on self-join using the offset indexes as the keys. This will make the remaining steps trivially easy.
--Nate