How can I SUM merge dimension?

Hi experts,

I have one data provider with dimensión A and measure 1. Other data provider with dimensión B.

I need to fusión dimensión A and dimensión B = C

I need show aggregate for dimensión B and measure 1.

the problema is that I'm having allwais agregte mesure for C.

Let me explain, If I make a table with dimensión B and mesure 1 and insert a total sum, the agregate is correct. but If I take out the dimensión B, the aggregate of measure 1 is for all values fusioned (C). I tried with Sum([mesure 1] IN ([dimensión B])) and no Works.

Anybody can help me with that?

thank you.