An expression without operators.
A PrimaryExpr defines some basic expressions that are used
in a FilterExpr. A Literal is a sequence of
characters that is enclosed either in double quotes (then it must not contain a
double quote) or in single quotes (then it must not contain a single quote).
It corresponds to the expression PrimaryExpr defined in
XPath, Section 3.1,
Rule 15 with the restriction that XPath also supports a
VariableReference which is not supported in X-Query.
Literal and Number correspond to the
respective XPath expressions, as defined in the
Section 3.7,
Rules 29 and 30.
The string value is a Literal:
'Atkins'
Select all data of a patient except his or her name and any remarks
(from all immediate child element nodes of the patient nodes
select the siblings following the name node provided that they are
not the last one):
(/patient/* after name)[position() != last()]
You get this result only by enclosing the SequenceExpr in
parentheses. Otherwise the predicate expression would be applied to the
name node instead of to the whole sibling node set and this would
yield an empty result set.
| OrExpr | FunctionCall |