Problems on CDS Views performance

Hi Guys,

I'm having problems with CDS View now, I have a table ACDOCA which has 400 million rows, and in the CDS View(say CDS View Main),  ACDOCA(only some fields are used) is used to join 3 other tables.

And I found in PlanViz that all 400 million rows are used to do the join, it consumes a log memory and VERY SLOW.

I write a CDS view(CDS View Agg) in which I select the used fields from ACDOCA and do the aggregation, the result is about 1 million rows, then I use CDS View Agg in CDS View Main to replace ACDOCA.

I thought this should solve the performance problem, but it didn't. In PlanViz I still see 400 million in join.

Please help how to avoid doing such weird thing, I don't think there's any benifit in it.

Regards,

Blangero