HP e-Commerce / XML director server appliance sa8250 - Users Guide

C H A P T E R 2 XML Operations
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The operative component of a FilterExpression is a comparison
expression or any FunctionCall expression that returns a string value,
which compares either an element or an attribute against a specified
value. An element in a FilterExpression refers to the child element of
the context node, while an attribute refers to the attribute of the
context node.
Comparison expression syntax:
(Element | Attribute | FunctionCall)
ComparisonOperator Value
FunctionCall expression syntax:
FunctionName ’(’ (Argument (’,’ Argument)*)? ’)’
For more information on Function Calls, see “Function Calls” later in
this chapter.
You can combine comparison expressions and the FunctionCall
expression with Boolean operators and parentheses to create complex
filter expressions, as shown in this table.
Sample Pattern Description
//employee[grade=5]
Matches if an employee element with a child element grade
value equal to 5
//name[@lastName=
”Smith”]
Matches if a name element with an attribute lastName=Smith
//employee[grade=5] and
//grade[@title=
”manager”]
Matches if an employee element with a child element grade
value equal to 5 and a child element with an attribute
title=”manager”
Comparison Expression Samples