Count Distinct Formula

[gheyman]

I need a formula that can count distinct value for a vendor.

Vendor A	1234
Vendor A	4563
Vendor B	ABC
Vendor B	DEF
Vendor A	1234

in this example I would want to know how many distinct part numbers for Vendor A - so the formula should result in 2 (it should not count the second 1234 for Vendor A

Any help is very much appreciated. Thank you

 

[Fluff]

How about

=rows(unique(filter(b2:b100,a2:a100="Vendor A")))

 

[etaf]

Edit

Fluff has answered

maybe a better way

=COUNTA(UNIQUE(FILTER($B$1:$B$13,$A$1:$A$13=E1)))

Book10
	A	B	C	D	E	F
1	Vendor A	1234			Vendor A	2
2	Vendor A	4563			Vendor B	3
3	Vendor B	ABC
4	Vendor B	DEF
5	Vendor A	1234
6	Vendor B	DEF
7	Vendor B	abb
Sheet1

Cell Formulas
Range	Formula
E1:E2	E1	=UNIQUE(A1:A5)
F1:F2	F1	=COUNTA(UNIQUE(FILTER($B$1:$B$13,$A$1:$A$13=E1)))
Dynamic array formulas.