Populate cell based on unique values from two fields

Question

I have a data set similar to the google sheet image below. I currently have a formula in column C that populates the first unique value in column B.

ARRAYFORMULA(INDEX(IF(B2:B="""",,IF(COUNTIFS(B2:B, B2:B, ROW(B2:B), ""<=""&ROW(B2:B))=1, 1, )))

However I need a formula to return what is in column D. This populates the cell for the first row that has both a unique 'Color' and 'Name'. For example, row 2 is populated for Purple - James and row 12 for White - James. But row 38 for Purple - James is not populated.

Answer 1

Use map() and filter(), like this:

=map(A2:A, B2:B, lambda(color, name, 
  if( 
    rows(filter(B2:name, A2:color = color, B2:name = name)) = 1, 
    1, 
    iferror(ø) 
  ) 
))

If you just want to get a list of unique color-name pairs, use this:

=unique(A2:B)

See map(), filter() and unique().