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<?xml version="1.0" encoding="ISO-8859-1"?>
<refentry id="XP-V-3">
  <refmeta>
    <refentrytitle>Using XPath queries to XML views</refentrytitle>
    <refmiscinfo>tutorial</refmiscinfo>
  </refmeta>
  <refnamediv>
    <refname>Examples</refname>
    <refpurpose>Using XPATH in SQL Queries and Procedures.</refpurpose>
  </refnamediv>

<refsect1 id="XP-V-3a">
<title>Example</title>
<para>
An XPATH expression can appear as a SQL query expression, that is, as a derived table or subquery 
predicate or scalar subquery. This means that the XPATH expression is expanded compile time to the 
corresponding SQL. 
</para>
<para> The query</para>

<programlisting><![CDATA[
select * from (XPATH '[__* __view "DB"."DBA"."cat"]//product/@ProductName') P order by P."ProductName"
]]></programlisting>

<para>will evaluate the //product query in the context of the &apos;cat&apos; XML view and produce a result 
set consisting of the ordered &apos;ProductName&apos; attributes of the product entity as defined in the view:
</para>
<programlisting><![CDATA[
ProductName
VARCHAR
_______________________________________________________________________________

Alice Mutton
Aniseed Syrup
Boston Crab Meat
Camembert Pierrot
Carnarvon Tigers
Chai
Chang
Chartreuse verte
.  .  .  .  .  .   
Zaanse koeken   
]]></programlisting>
</refsect1>

</refentry>
