V$ACTIVE_SERVICES displays information about the active services in the database.
Name of the service
Service name hash
Creation date hash
Service workload management goal:
Indicates whether the service is for DTP or distributed transactions including XA transactions (Y) or not (N)
Indicates whether a service on the specified instance is blocked from accepting new connections altogether (YES) or not (NO). If a service is blocked, then all connections will be directed to other instances (if any) that are hosting the desired service.
Indicates whether AQ notifications are sent for HA events (YES) or not (NO)
Connection load balancing goal used with statistics that are sent to the listeners to determine how new connections are distributed: