Need to split and distribute xslt nodes

January 5, 2022

Need to transform XML structure mentioned below using XSLT 2.0 or 3.0,

from

<RD>
    <RE>
        <BI>B00</BI>
        <BI>B01</BI>
        <BI>B02</BI>
        <BI>B03</BI>
        <CI>C01</CI>
        <D>D01</D>
    </RE>
    <RE>
        <BI>B04</BI>
        <BI>B05</BI>
        <CI>C02</CI>
        <D>D02</D>
    </RE>
</RD>

to this:

<RD>
    <RE>
        <BI>B00</BI>
        <CI>C01</CI>
        <D>D01</D>
    </RE>
    <RE>
        <BI>B01</BI>
        <CI>C01</CI>
        <D>D01</DI>
    </RE>
    <RE>
        <BI>B02</BI>
        <CI>C01</CI>
        <D>D01</D>
    </RE>
    <RE>
        <BI>B03</BI>
        <CI>C01</CI>
        <D>D01</D>
    </RE>
    <RE>
        <BI>B04</BI>
        <CI>C02</CI>
        <D>D02</D>
    </RE>
    <RE>
        <BI>B05</BI>
        <CI>C02</CI>
        <D>D02</D>
    </RE>
</RD>

Explanation:
I need to achieve the distribution of XML nodes of (CI),(D) to each of (BI) tags in every iteration of (RE) tag

>Solution :

You can treat it as a grouping problem:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  version="3.0"
  xmlns:xs="http://www.w3.org/2001/XMLSchema"
  exclude-result-prefixes="#all"
  expand-text="yes">

  <xsl:output method="html" indent="yes"/>
  
  <xsl:template match="RD">
    <xsl:copy>
      <xsl:for-each-group select="RE" group-by="BI">
        <xsl:copy>
          <BI>{current-grouping-key()}</BI>
          <xsl:apply-templates select="*[not(self::BI)]"/>
        </xsl:copy>
      </xsl:for-each-group>
    </xsl:copy>
  </xsl:template>

  <xsl:mode on-no-match="shallow-copy"/>

</xsl:stylesheet>