This is a subtype of AuditHistoryUpdateEventTypeand is used for categorization of history value update related Events. This type follows all the behaviour of its parent type. Its representation in the AddressSpaceis formally defined in Table 11.

Table 11– AuditHistoryValueUpdateEventType definition

Attribute	Value
BrowseName	AuditHistoryValueUpdateEventType
IsAbstract	True
References	NodeClass	BrowseName	DataType	TypeDefinition	ModellingRule
Subtype of the AuditHistoryUpdateEventTypedefined in OPC 10000-3, i.e. it has HasProperty Referencesto the same Nodes.
HasProperty	Variable	UpdatedNode	NodeId	PropertyType	Mandatory
HasProperty	Variable	PerformInsertReplace	PerformUpdateType	PropertyType	Mandatory
HasProperty	Variable	NewValues	DataValue[]	PropertyType	Mandatory
HasProperty	Variable	OldValues	DataValue[]	PropertyType	Mandatory

This EventTypeinherits all Propertiesof the AuditHistoryUpdateEventType. Their semantic is defined in OPC 10000-3.

The UpdatedNodeidentifies the Attributethat was written on the SourceNode.

The PerformInsertReplace enumeration reflects the parameter on the Servicecall.

The NewValuesidentify the value that was written to the Event.

The OldValuesidentify the value that the Eventcontained before the write. It is acceptable for a Serverthat does not have this information to report a null value. In the case of an insert it is expected to be a null value.

Both the NewValuesand the OldValueswill contain a value in the DataTypeand encoding used for writing the value.