How to count distinct a field cumulatively using recursive cte or other method in SQL?

Question

Using example below, Day 1 will have 1,3,3 distinct name(s) for A,B,C respectively. When calculating distinct name(s) for each house on Day 2, data up to Day 2 is used. When calculating distinct name(s) for each house on Day 3, data up to Day 3 is used.

Can recursive cte be used?

Data:

Day	House	Name
1	A	Jack
1	B	Pop
1	C	Anna
1	C	Dew
1	C	Franco
2	A	Jon
2	B	May
2	C	Anna
3	A	Jon
3	B	Ken
3	C	Dew
3	C	Dew

Result:

Day	House	Distinct names
1	A	1
1	B	1
1	C	3
2	A	2 (jack and jon)
2	B	2
2	C	3
3	A	2 (jack and jon)
3	B	3
3	C	3

Answer 1

Without knowing the need and size of data it'll be hard to give an ideal/optimal solution. Assuming a small dataset needing a quick and dirty way to calculate, just use sub query like this...

SELECT p.[Day]
    , p.House
    , (SELECT COUNT(DISTINCT([Name]))
        FROM #Bing
        WHERE [Day]<= p.[Day] AND House = p.House) DistinctNames
FROM #Bing p
GROUP BY [Day], House
ORDER BY 1