Concatenate multiple node values in xpath

I used concat method and works well.

concat(//SomeElement/text(),'_',//OtherElement/text())

Try this expression...

string-join(//element3/(concat(element4/text(), '.', element5/text())), "
")

for $d in $doc/element2/element3 return fn:string-join(fn:data($d/element()), ".").
$doc stores the Xml.

Here comes a solution with XSLT:

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="//element3">
    <xsl:value-of select="element4/text()" />.<xsl:value-of select="element5/text()" />
</xsl:template>
</xsl:stylesheet>