XMLTRANSFORM

Syntax

Description of XMLTransform.gif follows
Description of the illustration XMLTransform.gif

Purpose

XMLTransform takes as arguments an XMLType instance and an XSL style sheet, which is itself a form of XMLType instance. It applies the style sheet to the instance and returns an XMLType.

This function is useful for organizing data according to a style sheet as you are retrieving it from the database.

Examples

The XMLTransform function requires the existence of an XSL style sheet. Here is an example of a very simple style sheet that alphabetizes elements within a node:

CREATE TABLE xsl_tab (col1 XMLTYPE);
INSERT INTO xsl_tab VALUES (
 XMLTYPE.createxml(
 '<?xml version="1.0"?> 
 <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" >
 <xsl:output encoding="utf-8"/>
 <!-- alphabetizes an xml tree --> 
 <xsl:template match="*"> 
 <xsl:copy>
 <xsl:apply-templates select="*|text()">
 <xsl:sort select="name(.)" data-type="text" order="ascending"/>
 </xsl:apply-templates> 
 </xsl:copy> 
 </xsl:template>
 <xsl:template match="text()"> 
 <xsl:value-of select="normalize-space(.)"/>
 </xsl:template>
 </xsl:stylesheet> '));
1 row created.

The next example uses the xsl_tab XSL style sheet to alphabetize the elements in one warehouse_spec of the sample table oe.warehouses:

SELECT XMLTRANSFORM(w.warehouse_spec, x.col1).GetClobVal()
 FROM warehouses w, xsl_tab x
 WHERE w.warehouse_name = 'San Francisco';
XMLTRANSFORM(W.WAREHOUSE_SPEC,X.COL1).GETCLOBVAL()
--------------------------------------------------------------------------------
<Warehouse>
 <Area>50000</Area>
 <Building>Rented</Building>
 <DockType>Side load</DockType>
 <Docks>1</Docks>
 <Parking>Lot</Parking>
 <RailAccess>N</RailAccess>
 <VClearance>12 ft</VClearance>
 <WaterAccess>Y</WaterAccess>
</Warehouse>