Hi,

> I have two XML and I want to mix them depending on a element 
> value , like 
> two tables with a relation in a relational database

[snip]

> And I want to generate next xml.The element used as 'key' is id_book:

[snip]

> How could I do this?

Process the first source document with stylesheet,

  <xsl:variable name="secondDocument" select="document('secondDocument.xml')/pages/page"/>

  <xsl:template match="@*|node()">
    <xsl:copy>
      <xsl:apply-templates select="@*|node()" />
    </xsl:copy>
  </xsl:template>

  <xsl:template match="book">
    <xsl:copy>
      <xsl:apply-templates select="@*|node()" />
      <xsl:apply-templates select="$secondDocument[id_book = current()/id_book]"/>
    </xsl:copy>
  </xsl:template>

  <xsl:template match="id_book[parent::page]" />

Cheers,

Jarno

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