V$PX_INSTANCE_GROUP

V$PX_INSTANCE_GROUP provides information about the instance groups being used for parallel operations by the current session.

Column Datatype Description

QC_INSTANCE_GROUP VARCHAR2(64) The instance group being used by this session for parallel operations. This value repeats for every row returned.

Column	Datatype	Description
`QC_INSTANCE_GROUP`	`VARCHAR2(64)`	The instance group being used by this session for parallel operations. This value repeats for every row returned.
`WHY`	`VARCHAR2(23)`	Where the current instance group name comes from, as follows: SERVICE - the instance group being used is from the session's service name PARALLEL_INSTANCE_GROUP - the instance group being used is being used because the PARALLEL_INSTANCE_GROUP initialization parameter has been set. The value repeats for every row returned.
`INSTANCE_NUMBER`	`NUMBER`	Instance number of the instance providing this instance group. There will be one row for each instance in the instance group that the Query Coordinator is using.

WHY

VARCHAR2(23)

Where the current instance group name comes from, as follows:

SERVICE - the instance group being used is from the session's service name

PARALLEL_INSTANCE_GROUP - the instance group being used is being used because the PARALLEL_INSTANCE_GROUP initialization parameter has been set.

The value repeats for every row returned.

INSTANCE_NUMBER NUMBER Instance number of the instance providing this instance group. There will be one row for each instance in the instance group that the Query Coordinator is using.