In Google Spreadsheet, I have a query:

=QUERY({dataset1, dataset2}, "SELECT Col1,Col2,Col3,Col4 WHERE ...");

This outputs 4 columns. I’d like to concatenate Col2 and Col3 (only) such as the output is: Col1, Col2 + " " + Col3, Col4

I found How to use CONCAT in QUERY? and related blogs that all explain how to concatenate all columns with a double transpose, but this isn’t what I need. I want to choose the subset of columns I want to concatenate (without modifying any of the original datasets). Trying to do this without an Apps Script either…