Non-Partitioned Query Scale-Out

For non-partitioned data, new JOIN and GROUP BY algorithms reduce the amount of intermediate results that are exchanged during distributed query execution.

These new features improve query performance in cases limited by shared temp or interconnect bandwidth. The optimizer automatically selects these new operators on a cost basis. No user intervention is required but some limitations apply:

The optimizer has a limited cost mode for the new algorithms. It may not use them in all cases where they may provide benefit or may use them sub-optimal situations
New grouping algorithms are limited to non-null data