New Dax column from a many to many bidirectional relationship

[Anonymous]

Hi, i have two tables, 'Sales' and 'Header' with a many to many relationship by [Client]
I have this structure

Sales		Header
Client		Client	Amount
C1		C1	1
C1		C1	2
C2		C2	3
C2		C2	4
		C2	5
C3
		C4	6

And I want to create a new column with dax in a 'Sales' table containing the sum of the amount of each [Client] from 'Header'.

Sales		Header
Client	NewColumDAX	Client	Amount
C1	3	C1	1
C1	3	C1	2
C2	12	C2	3
C2	12	C2	4
		C2	5
C3	0
		C4	6

How can i do?
Thanks very much for any help

[v-cherch-msft · Accepted solution]

Hi @Anonymous 

You may link the two tables and use below dax to get the calculated column.

Column = CALCULATE(SUM(Header[Amount]))+0

Regards,

[Anonymous]

Yes Thanks!!!