dbxmlBooleanQuery

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Module

The dbxmlBooleanQuery accessor is exported by the urn:org:ten60:netkernel:mod:dbxml module. Import this module to gain access to the accessor.

Syntax

URI

active:dbxmlBooleanQuery

Argument	Rules	Description
operator	Mandatory	the query specification

Example Usage

DPML

<instr>
  <type>dbxmlBooleanQuery</type>
  <operator>
    <dbxml>
      <container>mycontainer</container>
      <xquery>
                    
                    &lt;root&gt;
                        {    collection('mycontainer')/root
                        }
                    &lt;/root&gt;
                    
                </xquery>
    </dbxml>
  </operator>
  <target>var:resultset</target>
</instr>

NetKernel Foundation API

req=context.createSubRequest("active:dbxmlBooleanQuery");
req.addArgument("operator", [resource representation, aspect, or URI] );
result=context.issueSubRequest(req);

Purpose

The dbxmlBooleanQuery accessor performs an XQuery on the Berkeley DBXML database - if the result set contains any values it returns true. If the result set is empty it returns false. The response is a BooleanAspect.

Operator Format

The format for the operator is...

<dbxml>
  <container>someContainerName</container>
  <xquery>
        ...Must be a CDATA Section containing XQuery...
    </xquery>
</dbxml>

The container tag specifies the identity of the container in the BDBXML database to query. For details of the XQuery syntax see the references below.

Reference

Berkeley DBXML can be downloaded from Sleepycat Software.
Javadoc for BDBXML