Metadata group

These variables allow access to an arbitrary field in any dataset associated with the job (external metadata or embedded metadata).

There is a variable for each data type supporting the appropriate formatting and/or indexing arguments. This enables the user to express the expected data type for the metadata value and control its formatting.

Variable name	Data type
Metadata.Text	Text
Metadata.TextIndexed	Text Indexed
Metadata.Boolean	Boolean
Metadata.Integer	Integer
Metadata.Rational	Rational
Metadata.Date	Date

Selecting a data field

The variables in the Metadata group support the following arguments for selecting a particular metadata field from a particular dataset.

Argument	Value
Dataset	The name of the external dataset to be accessed, or empty/missing to indicate the embedded dataset
Model	The data model used for querying the data set; when empty/missing the data model is derived from the dataset; allowed values are "XML", "JDF" and "XMP" This argument can be omitted except when forcing a JDF data model to be queried using regular XML semantics (that is, using "evalToString" rather than "getString")
Path	The location path or expression for selecting a field (or calculating a value) using syntax appropriate for the data model: XML: XPath expression (which includes XPath location paths) JDF: JDF location path (which is really the same as an XPath location path) XMP: XMP location path All prefixes used in the location path or expression must occur in the default namespace map for the data set; there is no way to specify explicit mappings

Argument

Value

Dataset

The name of the external dataset to be accessed, or empty/missing to indicate the embedded dataset

Model

The data model used for querying the data set; when empty/missing the data model is derived from the dataset; allowed values are "XML", "JDF" and "XMP"

This argument can be omitted except when forcing a JDF data model to be queried using regular XML semantics (that is, using "evalToString" rather than "getString")

Path

The location path or expression for selecting a field (or calculating a value) using syntax appropriate for the data model:

XML: XPath expression (which includes XPath location paths)
JDF: JDF location path (which is really the same as an XPath location path)
XMP: XMP location path
All prefixes used in the location path or expression must occur in the default namespace map for the data set; there is no way to specify explicit mappings

Data type conversions

Switch does not guarantee that the value of a variable in the Metadata category conforms to the string representation of its data type. The user is responsible for selecting the correct data type by using the appropriate variable in the Metadata category.

The variable is always set to the string value of the query (for Text Indexed, each item in the list is converted separately).

In other words:

For the JDF and XMP data models there is never a conversion, because the result of the query is always a string (the text content of the node specified by the location path).
For the XML data model, the result of the XPath expression is converted to a string using XPath semantics (unless it was a string to begin with).