Specifies which operator will be notified of the occurrence of
    a database system event. You can specify the following operator
    classes:

    Operator
    Class          Meaning

    ALL            The ALL operator class broadcasts a message to
                   all terminals that are enabled as operators and
                   that are attached to the system or cluster. These
                   terminals must be turned on and have broadcast-
                   message reception enabled.
    NONE           The NONE operator class inhibits the display of
                   messages to the entire system or cluster.
    [NO] CENTRAL   The CENTRAL operator class broadcasts messages
                   sent to the central system operator. The NO
                   CENTRAL operator class inhibits the display of
                   messages sent to the central system operator.
    [NO] DISKS     The DISKS operator class broadcasts messages
                   pertaining to mounting and dismounting disk
                   volumes. The NO DISKS operator class inhibits
                   the display of messages pertaining to mounting and
                   dismounting disk volumes.
    [NO] CLUSTER   The CLUSTER operator class broadcasts messages
                   from the connection manager pertaining to
                   cluster state changes. The NO CLUSTER operator
                   class inhibits the display of messages from the
                   connection manager pertaining to cluster state
                   changes.
    [NO] CONSOLE   The CONSOLE class broadcasts messages to the
                   Oracle Enterprise Manager (OEM). NO CONSOLE
                   inhibits broadcast to OEM.
    [NO]           The SECURITY operator class displays messages
    SECURITY       pertaining to security events. The NO SECURITY
                   operator class inhibits the display of messages
                   pertaining to security events.
    [NO] OPER1     The OPER1 through OPER12 operator classes display
    through [NO]   messages to operators identified as OPER1 through
    OPER12         OPER12. The NO OPER1 through NO OPER12 operator
                   classes inhibit messages from being sent to the
                   specified operator.