Specify the type of an XQuery value.
A SequenceType
specifies the type of an XQuery value by
identifying it either as an item type together with an occurrence indicator or
as an empty sequence using empty()
. An item type can be the
qualified name or any of the node tests available in Tamino XQuery. Since a
value is always a sequence, you can use an occurrence indicator specifying the
number of items in the sequence:
?
specifies one or zero items
*
specifies zero or more items
+
specifies one or more items
Some sequence types that you can use in XQuery expressions:
xs:date
refers to the built-in atomic schema type named
xs:date
attribute()?
refers to an optional attribute
element(name)
refers to an element called
name
of any type
node()*
refers to a sequence of zero or more nodes of any
type
item()+
refers to a sequence of one or more nodes or
atomic values
The following construct(s) refer to this construct: