Feature request: a flag to rename fields for summary command

[stas-malavin]

Hello,

How about a possibility to rename columns right inside the summary command? Or just to keep them as is without adding the actual summary function to the column name.

Motivation: if it's in a pipeline, I don't want long [changing] names, as I'll address the summarized fields later in the pipeline. I know I can add-header, but that's a whole extra command.