Hallo Mobby,
probiere diesen Ansatz:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xpath-default-namespace="http://www.filemaker.com/fmpdsoresult"
xmlns="http://www.filemaker.com/fmpdsoresult">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>
<xsl:template match="FMPDSORESULT">
<FMPDSORESULT>
<xsl:for-each-group select="ROW" group-by="Hauptartikel">
<xsl:for-each select="current-group()[1]">
<ROW>
<Hauptartikel>
<xsl:value-of select="Hauptartikel"/>
</Hauptartikel>
<xsl:for-each select="current-group()">
<ROW2>
<xsl:copy-of select="Hauptartikel/following-sibling::*"/>
</ROW2>
</xsl:for-each>
</ROW>
</xsl:for-each>
</xsl:for-each-group>
</FMPDSORESULT>
</xsl:template>
</xsl:stylesheet>
Grüße,
Thomas