![OUTPUT_NULLS option [ISQL]](arrow-left.gif){kind=icon}
Allows GROUP BY operations on a single table to be executed in parallel using all available CPUs, if determined appropriate by the optimizer.
ON, OFF
Can be set temporary, for an individual connection, or for the PUBLIC group. Takes effect immediately.
ON
The PARALLEL_GBH_ENABLED option causes GROUP BY operations on a single table to be done in parallel using all available CPUs. This option provides significant performance gains for some queries in certain situations.
PARALLEL_GBH_ENABLED is ON by default. You can disable this feature by setting PARALLEL_GBH_ENABLED to OFF or constrain the effect by changing the value of the PARALLEL_GBH_UNITS option.
