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6.3.2 Using Dictionary References

HasDictionaryEntry is used to define the relationship to a Syntax Reference by referencing from quantity or unit Nodes to an instance of a SyntaxReferenceEntryType. Each quantity or unit instance can have zero, one or more such references.

Instances of SyntaxReferenceEntryType have a well-defined NodeId as defined in Table 34.

Table 34 – Definition of NodeId for instances of the SyntaxReferenceEntryType

Name

Type

Definition for instances of the SyntaxReferenceEntryType

NodeId

structure

namespaceIndex

UInt16

The NamespaceTable index for the Syntax Reference URI (see Table 33).

IdType

Enum

String

identifier

*

The Syntax Reference identifier (SyntaxReferenceId), see 6.3.3

When calling the Browse Service for a Quantity or Unit Node, the response includes the HasDictionaryEntry Reference together with the well-defined NodeId for the SyntaxReferenceEntryType instance. The actual instance therefore is not required in the AddressSpace.

Figure 7 provides an example of References to external works.

image010.png

Figure 7 – References to external works

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