12.16 ModelChangeStructureDataType

This structure contains elements that describe changes of the model. Its composition is defined in Table 245.

Table 245 – ModelChangeStructureDataType Structure

Name

Type

Description

ModelChangeStructureDataType

structure

affected

NodeId

NodeId of the Node that was changed. The client should assume that the affected Node has been created or deleted, had a Reference added or deleted, or the DataType has changed as described by the verb.

affectedType

NodeId

If the affected Node was an Object or Variable, affectedType contains the NodeId of the TypeDefinitionNode of the affected Node. Otherwise it is set to null.

verb

Byte

Describes the changes happening to the affected Node.

The verb is an 8-bit unsigned integer used as bit mask with the structure defined in the following table:

Field

Bit

Description

NodeAdded

0

Indicates the affected Node has been added.

NodeDeleted

1

Indicates the affected Node has been deleted.

ReferenceAdded

2

Indicates a Reference has been added. The affected Node may be either a SourceNode or TargetNode. Note that an added bidirectional Reference is reflected by two changes one with the affected Node being the SourceNode, and the second with the affected Node being the TargetNode.

ReferenceDeleted

3

Indicates a Reference has been deleted. The affected Node may be either a SourceNode or TargetNode. Note that a deleted bidirectional Reference is reflected by two changes one with the affected Node being the SourceNode, and the second with the affected Node being the TargetNode.

DataTypeChanged

4

This verb may be used only for affected Nodes that are Variables or VariableTypes. It indicates that the DataType Attribute has changed.

Reserved

5:7

Reserved for future use. Shall always be zero.

A verb may identify several changes on the affected Node at once. This feature should be used if event compression is used (see OPC 10000-3 for details).

Note that all verbs shall always be considered in the context where the ModelChangeStructureDataType is used. A NodeDeleted may indicate that a Node was removed from a view but still exists in other Views.

Its representation in the AddressSpace is defined in Table 246.

Table 246 – ModelChangeStructureDataType definition

Attributes

Value

BrowseName

ModelChangeStructureDataType

IsAbstract

FALSE

References

NodeClass

BrowseName

DataType

TypeDefinition

ModellingRule

Subtype of the Structure DataType defined in Table 187.

Conformance Units

Base Info Model Change General