XML/XQuery/function — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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(нет различий)
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Текущая версия на 08:25, 26 мая 2010
Define your own function
Simple function
File: Query.xquery
declare namespace math = "http://wbex.ru";
declare function math:add($op1 as xs:integer, $op2 as xs:integer) as xs:integer
{
$op1 + $op2
};
declare variable $op1 as xs:integer := 1;
declare variable $op2 as xs:integer := 2;
<add>
<op1>{$op1}</op1>
<op2>{$op2}</op2>
<result>{math:add($op1, $op2)}</result>
</add>
Output:
<?xml version="1.0" encoding="UTF-8"?>
<add>
<op1>1</op1>
<op2>2</op2>
<result>3</result>
</add>
Recursive function
File: Query.xquery
declare namespace math = "http://wbex.ru";
declare variable $n as xs:integer external;
declare function math:factorial($integer as xs:integer) as xs:double
{
if ($integer gt 1) then $integer * math:factorial($integer - 1) else 1
};
concat(2, "! = ", math:factorial(2))
Output:
<?xml version="1.0" encoding="UTF-8"?>2! = 2
Useful-function: between-inclusive
File: Data.xml
<order>
<car model="A">
<id>1</id>
<name language="en">name 1</name>
<colorChoices>navy black</colorChoices>
</car>
<car model="B">
<id>2</id>
<name language="en">name 2</name>
</car>
<car model="B">
<id>8</id>
<name language="en">name 3</name>
</car>
</order>
File: Query.xquery
declare namespace functx = "http://www.wbex.ru";
declare function functx:between-inclusive
($value as xs:anyAtomicType, $minValue as xs:anyAtomicType,$maxValue as xs:anyAtomicType) as xs:boolean {
$value >= $minValue and $value <= $maxValue
};
(: Example call :)
let $prod := doc("Data.xml")//car[1]
return functx:between-inclusive ($prod/id, 1, 5)