Join index

Hi,  I want to optimize the runtime of this query Select sum(a.C4), b.C1, b.C2, b.C3 from v1 a, v2 b where (b.C1 = a.C1 and b.C2 = a.C2 and b.C3 = a.C3) or (b.C1 = a.C1 and b.C2 = a.C2 and b.C3 = 0) or (b.C1 = a.C1 and b.C2 = 0 and b.C3 = 0) or (b.C1 = 0 and b.C2 = 0 and b.C3 = 0) group by b.C1, b.C2, b.C3; why I thought of creating a BITMAP index join or create a bitmap index for v1 columns (c1, c2, c3) and v2 (c1, c2, c3). I can't do this with MonetDB can you help me.