Grouping XSLT elements by value (XSLT 1.0)

Question

I am having a really hard time trying to group different elements by a common value using XSLT 1.0.

Using the following XML:

<root>
    <segment>
        <id>ABCD123</id>
    </segment>
    <segment>
        <contact>
            <field1>ABCD123</field1>
            <field2>(111)345-7890</field2>
        </contact>
    </segment>
    <segment>
        <details>
            <field1>ABCD123</field1>
            <field5>More Details for ABCD123</field5>
        </details>
    </segment>
    <segment>
        <id>XZX098</id>
    </segment>
    <segment>
        <contact>
            <field1>XZX098</field1>
            <field2>(111)443-9999</field2>
        </contact>
    </segment>
    <segment>
        <details>
            <field1>XZX098</field1>
            <field5>More Details for XZX098</field5>
        </details>
    </segment>
</root>

Transform into this:

<File>
    <Record>
        <id>ABCD123</id>
        <phone>(111)345-7890</phone>
        <details>More Details for ABCD123</details>
    </Record>
    <Record>
        <id>XZX098</id>
        <phone>(111)443-9999</phone>
        <details>More Details for XZX098</details>
    </Record>
</File>

I'm trying to group records by the 'id', and then get the contact, and details information that matches that 'id'.

Any help is greatly appreciated.

Your XML sample is too small to deduct a system from it. Please extend you XML files and also add an attempt to solve it. — zx485

michael.hor257k michael.hor257k · Accepted Answer · 2020-06-21T05:32:46

I don't see any grouping per se required here - just a simple lookup of cross-referenced data:

XSLT 1.0

<xsl:stylesheet version="1.0" 
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>

<xsl:key name="contact-details" match="contact|details" use="field1" />

<xsl:template match="root">
    <File>
        <xsl:for-each select="segment/id">
            <Record>
                <xsl:copy-of select="."/>
                <phone>
                    <xsl:value-of select="key('contact-details', .)/field2"/>
                </phone>
                <details>
                    <xsl:value-of select="key('contact-details', .)/field5"/>
                </details>
            </Record>
        </xsl:for-each>
    </File>
</xsl:template>

</xsl:stylesheet>

Grouping XSLT elements by value (XSLT 1.0)

1 Answers