Once Adaptive Server is configured for parallel create index, it determines if using parallel execution to execute create index is the best choice. If Adaptive Server determines that a serial query plan is the most efficient, it does not use a parallel query plan. If Adaptive Server determines that a parallel query plan is the most efficient, it selects an enhanced parallel query plan if:
The table upon which the index is to be created:
Uses a data-only-locked format, and
Is not partitioned, and
The table is not empty
The index you are creating is a non-clustered index, and
The leading column of the index has at least two distinct values
Use the create index ... with consumers = N to force Adaptive Server to use parallel query plans when it would typically use a serial query plan. For example, Adaptive Server uses parallel query plans for the following even though if the table contains too few rows:
create index i1 on t1(c1, c3) with consumers = 3
If you use with consumers to force a parallel create index, and Adaptive Server does not select an enhanced parallel query plan, Adaptive Server uses a parallel create index query plan from a version of Adaptive Server earlier than 15.7 ESD #2.
