Google sheets formula to count and filter one column based on another column

Question

I am trying to count/sum the number of days for each option in the "Who" column.

In this example the results would be: ALL: 1 BOTH: 3 TOM: 2

Thinking it would require filtering column B based on column D?

Any ideas?

Answer 1

Try

=QUERY(B:D,"select D,SUM(B) where D <>'' group by D")