I have two spreadsheets. The first one has a column with numbers in it.
The second one has a column with the same numbers and a description
column as well. Each number can have more than one description. What I
want to do do is iterate the rows in Sheet 1 and lookup the numbers in
sheet 2. Then return all the descriptions to sheet 1 and put them in
the cell next to the number. If there are multiple descriptions for a
number we would like them separated by a comma. Is there a function for
something like this?

TIA