Title: XQuery Extensions
Category: documentation

## Overview

<div class="alert alert-warning">
    XQuery is available only in ODE 1.3 or later
</div>

Apache ODE goes above and beyond the [WS-BPEL](/ws-bpel-20.html) specification by allowing the use of [XQuery 1.0](http://www.w3.org/TR/xquery/) in queries and expressions.

Unless specified otherwise, WS-BPEL considers XPath 1.0 to be the query/expression language, which is denoted by the default value of the "queryLanguage" and "expressionLanguage" attributes, viz. "urn:oasis:names:tc:wsbpel:2.0:sublang:xpath1.0". In addition, we have out-of-the-box support for XPath 2.0.

<a name="XQueryExtensions-XQuery1.0"></a>
## XQuery 1.0

To use XQuery 1.0 in your processes just use the following _queryLanguage_ and _expressionLanguage_ attributes:

    queryLanguage="urn:oasis:names:tc:wsbpel:2.0:sublang:xquery1.0"
    expressionLanguage="urn:oasis:names:tc:wsbpel:2.0:sublang:xquery1.0"

If you want support at the process just add these attributes to your root _process_ element. If you want to stick with XPath 1.0 but want XQuery 1.0 support for a specific assignment you can also define these attributes on an _assign_ element.

For your convenience, all of the functions and variables, standard or otherwise, that are available in XPath 2.0 have been exposed in XQuery 1.0 as well.

<a name="XQueryExtensions-Examples"></a>
### Examples

The following snippet illustrates how to use XQuery 1.0 in _assign_ activities. Needless to say, you may use XQuery 1.0 anywhere an expression is permitted, such as in a _while_, _if_, _repeatUntil_ or _forEach_ activity.


    <process name="HelloXQueryWorld" 
        targetNamespace="http://ode/bpel/unit-test"
        xmlns:bpws="http://docs.oasis-open.org/wsbpel/2.0/process/executable"
        xmlns="http://docs.oasis-open.org/wsbpel/2.0/process/executable"
        xmlns:tns="http://ode/bpel/unit-test"
        xmlns:xsd="http://www.w3.org/2001/XMLSchema"
        xmlns:types="http://ode/bpel/types"
        xmlns:test="http://ode/bpel/unit-test.wsdl"
        xmlns:ode="http://www.apache.org/ode/type/extension"
        queryLanguage="urn:oasis:names:tc:wsbpel:2.0:sublang:xquery1.0"
        expressionLanguage="urn:oasis:names:tc:wsbpel:2.0:sublang:xquery1.0">
    
            ...
            <assign name="assign1">
                <copy>
                    <from variable="myVar" part="TestPart"/>
                    <to variable="otherVar"/>
                </copy>
                <copy>
                    <from><![CDATA[<test:content>Hello</test:content>]]></from>
                    <to variable="tempVar"/>
                </copy>
                <copy>
                    <from>
                        typeswitch ($myVar.TestPart) 
                          case $a as xs:string return "test"
                          default return "default"
                    </from>
                    <to variable="otherVar"/>
                </copy>
                <copy>
                    <from><![CDATA[
                        typeswitch ($myVar.TestPart) 
                          case $a as text() return <test:content/>
                          default return <test:content/>
                        ]]>
                    </from>
                    <to variable="otherVar"/>
                </copy>
                <copy>
                    <from>
                        for $loopOnce in (1) 
                        return 
                           concat(bpws:getVariableProperty("myVar", "test:content"), "XQuery World")
                    </from>
                    <to variable="myVar" part="TestPart"/>
                </copy>
            </assign>
            ...
        </sequence>
    </process>


<a name="XQueryExtensions-KnownLimitations"></a>
### Known Limitations

Currently, we do not support:
* The use of modules in XQuery.
* The use of update expressions in XQuery.